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<title>Reading and Writing Config Files</title>
<meta name="authors" content="Michael Foord Nicola Larosa" />
<meta name="date" content="2010/02/27" />
<meta content="ConfigObj - a Python module for easy reading and writing of config files." name="description" />
<meta content="python, script, module, config, configuration, data, persistence, developer, configparser" name="keywords" />
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<div class="document" id="reading-and-writing-config-files">
<h1 class="title">Reading and Writing Config Files</h1>
<h2 class="subtitle" id="configobj-4-introduction-and-reference">ConfigObj 4 Introduction and Reference</h2>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Authors:</th>
<td>Michael Foord
 Nicola Larosa</td></tr>
<tr><th class="docinfo-name">Version:</th>
<td>ConfigObj 4.7.2</td></tr>
<tr><th class="docinfo-name">Date:</th>
<td>2010/02/27</td></tr>
<tr class="field"><th class="docinfo-name">Homepage:</th><td class="field-body"><a class="reference external" href="http://www.voidspace.org.uk/python/configobj.html">ConfigObj Homepage</a></td>
</tr>
<tr class="field"><th class="docinfo-name">PyPI Entry:</th><td class="field-body"><a class="reference external" href="http://pypi.python.org/pypi/configobj/">ConfigObj on PyPI</a></td>
</tr>
<tr class="field"><th class="docinfo-name">Development:</th><td class="field-body"><a class="reference external" href="http://code.google.com/p/configobj/">Google Code Homepage</a></td>
</tr>
<tr class="field"><th class="docinfo-name">License:</th><td class="field-body"><a class="reference external" href="http://www.voidspace.org.uk/python/license.shtml">BSD License</a></td>
</tr>
<tr class="field"><th class="docinfo-name">Support:</th><td class="field-body"><a class="reference external" href="http://lists.sourceforge.net/lists/listinfo/configobj-develop">Mailing List</a></td>
</tr>
</tbody>
</table>
<div class="contents topic" id="configobj-manual">
ConfigObj Manual
<ul class="auto-toc simple">
<li><a class="reference internal" href="#introduction" id="id27">1&nbsp;&nbsp;&nbsp;Introduction</a></li>
<li><a class="reference internal" href="#downloading" id="id28">2&nbsp;&nbsp;&nbsp;Downloading</a><ul class="auto-toc">
<li><a class="reference internal" href="#installing" id="id29">2.1&nbsp;&nbsp;&nbsp;Installing</a></li>
<li><a class="reference internal" href="#documentation" id="id30">2.2&nbsp;&nbsp;&nbsp;Documentation</a></li>
<li><a class="reference internal" href="#development-version" id="id31">2.3&nbsp;&nbsp;&nbsp;Development Version</a></li>
</ul>
</li>
<li><a class="reference internal" href="#configobj-in-the-real-world" id="id32">3&nbsp;&nbsp;&nbsp;ConfigObj in the Real World</a></li>
<li><a class="reference internal" href="#getting-started" id="id33">4&nbsp;&nbsp;&nbsp;Getting Started</a><ul class="auto-toc">
<li><a class="reference internal" href="#reading-a-config-file" id="id34">4.1&nbsp;&nbsp;&nbsp;Reading a Config File</a></li>
<li><a class="reference internal" href="#writing-a-config-file" id="id35">4.2&nbsp;&nbsp;&nbsp;Writing a Config File</a></li>
<li><a class="reference internal" href="#config-files" id="id36">4.3&nbsp;&nbsp;&nbsp;Config Files</a></li>
</ul>
</li>
<li><a class="reference internal" href="#configobj-specifications" id="id37">5&nbsp;&nbsp;&nbsp;ConfigObj specifications</a><ul class="auto-toc">
<li><a class="reference internal" href="#methods" id="id38">5.1&nbsp;&nbsp;&nbsp;Methods</a><ul class="auto-toc">
<li><a class="reference internal" href="#write" id="id39">5.1.1&nbsp;&nbsp;&nbsp;write</a></li>
<li><a class="reference internal" href="#validate" id="id40">5.1.2&nbsp;&nbsp;&nbsp;validate</a><ul class="auto-toc">
<li><a class="reference internal" href="#return-value" id="id41">5.1.2.1&nbsp;&nbsp;&nbsp;Return Value</a></li>
<li><a class="reference internal" href="#mentioning-default-values" id="id42">5.1.2.2&nbsp;&nbsp;&nbsp;Mentioning Default Values</a></li>
<li><a class="reference internal" href="#mentioning-repeated-sections-and-values" id="id43">5.1.2.3&nbsp;&nbsp;&nbsp;Mentioning Repeated Sections and Values</a></li>
<li><a class="reference internal" href="#mentioning-simpleval" id="id44">5.1.2.4&nbsp;&nbsp;&nbsp;Mentioning SimpleVal</a></li>
<li><a class="reference internal" href="#mentioning-copy-mode" id="id45">5.1.2.5&nbsp;&nbsp;&nbsp;Mentioning copy Mode</a></li>
</ul>
</li>
<li><a class="reference internal" href="#reload" id="id46">5.1.3&nbsp;&nbsp;&nbsp;reload</a></li>
<li><a class="reference internal" href="#reset" id="id47">5.1.4&nbsp;&nbsp;&nbsp;reset</a></li>
</ul>
</li>
<li><a class="reference internal" href="#attributes" id="id48">5.2&nbsp;&nbsp;&nbsp;Attributes</a><ul class="auto-toc">
<li><a class="reference internal" href="#interpolation" id="id49">5.2.1&nbsp;&nbsp;&nbsp;interpolation</a></li>
<li><a class="reference internal" href="#stringify" id="id50">5.2.2&nbsp;&nbsp;&nbsp;stringify</a></li>
<li><a class="reference internal" href="#bom" id="id51">5.2.3&nbsp;&nbsp;&nbsp;BOM</a></li>
<li><a class="reference internal" href="#initial-comment" id="id52">5.2.4&nbsp;&nbsp;&nbsp;initial_comment</a></li>
<li><a class="reference internal" href="#final-comment" id="id53">5.2.5&nbsp;&nbsp;&nbsp;final_comment</a></li>
<li><a class="reference internal" href="#list-values" id="id54">5.2.6&nbsp;&nbsp;&nbsp;list_values</a></li>
<li><a class="reference internal" href="#encoding" id="id55">5.2.7&nbsp;&nbsp;&nbsp;encoding</a></li>
<li><a class="reference internal" href="#default-encoding" id="id56">5.2.8&nbsp;&nbsp;&nbsp;default_encoding</a></li>
<li><a class="reference internal" href="#unrepr" id="id57">5.2.9&nbsp;&nbsp;&nbsp;unrepr</a></li>
<li><a class="reference internal" href="#write-empty-values" id="id58">5.2.10&nbsp;&nbsp;&nbsp;write_empty_values</a></li>
<li><a class="reference internal" href="#newlines" id="id59">5.2.11&nbsp;&nbsp;&nbsp;newlines</a></li>
</ul>
</li>
</ul>
</li>
<li><a class="reference internal" href="#the-config-file-format" id="id60">6&nbsp;&nbsp;&nbsp;The Config File Format</a></li>
<li><a class="reference internal" href="#sections" id="id61">7&nbsp;&nbsp;&nbsp;Sections</a><ul class="auto-toc">
<li><a class="reference internal" href="#section-attributes" id="id62">7.1&nbsp;&nbsp;&nbsp;Section Attributes</a></li>
<li><a class="reference internal" href="#section-methods" id="id63">7.2&nbsp;&nbsp;&nbsp;Section Methods</a></li>
<li><a class="reference internal" href="#walking-a-section" id="id64">7.3&nbsp;&nbsp;&nbsp;Walking a Section</a></li>
<li><a class="reference internal" href="#examples" id="id65">7.4&nbsp;&nbsp;&nbsp;Examples</a></li>
</ul>
</li>
<li><a class="reference internal" href="#exceptions" id="id66">8&nbsp;&nbsp;&nbsp;Exceptions</a></li>
<li><a class="reference internal" href="#validation" id="id67">9&nbsp;&nbsp;&nbsp;Validation</a><ul class="auto-toc">
<li><a class="reference internal" href="#configspec" id="id68">9.1&nbsp;&nbsp;&nbsp;configspec</a></li>
<li><a class="reference internal" href="#type-conversion" id="id69">9.2&nbsp;&nbsp;&nbsp;Type Conversion</a></li>
<li><a class="reference internal" href="#default-values" id="id70">9.3&nbsp;&nbsp;&nbsp;Default Values</a><ul class="auto-toc">
<li><a class="reference internal" href="#id13" id="id71">9.3.1&nbsp;&nbsp;&nbsp;List Values</a></li>
</ul>
</li>
<li><a class="reference internal" href="#repeated-sections" id="id72">9.4&nbsp;&nbsp;&nbsp;Repeated Sections</a></li>
<li><a class="reference internal" href="#repeated-values" id="id73">9.5&nbsp;&nbsp;&nbsp;Repeated Values</a></li>
<li><a class="reference internal" href="#copy-mode" id="id74">9.6&nbsp;&nbsp;&nbsp;Copy Mode</a></li>
<li><a class="reference internal" href="#validation-and-interpolation" id="id75">9.7&nbsp;&nbsp;&nbsp;Validation and Interpolation</a></li>
<li><a class="reference internal" href="#extra-values" id="id76">9.8&nbsp;&nbsp;&nbsp;Extra Values</a></li>
<li><a class="reference internal" href="#simpleval" id="id77">9.9&nbsp;&nbsp;&nbsp;SimpleVal</a></li>
</ul>
</li>
<li><a class="reference internal" href="#empty-values" id="id78">10&nbsp;&nbsp;&nbsp;Empty values</a></li>
<li><a class="reference internal" href="#unrepr-mode" id="id79">11&nbsp;&nbsp;&nbsp;unrepr mode</a></li>
<li><a class="reference internal" href="#string-interpolation" id="id80">12&nbsp;&nbsp;&nbsp;String Interpolation</a><ul class="auto-toc">
<li><a class="reference internal" href="#string-interpolation-and-list-values" id="id81">12.1&nbsp;&nbsp;&nbsp;String Interpolation and List Values</a></li>
</ul>
</li>
<li><a class="reference internal" href="#comments" id="id82">13&nbsp;&nbsp;&nbsp;Comments</a></li>
<li><a class="reference internal" href="#flatten-errors" id="id83">14&nbsp;&nbsp;&nbsp;flatten_errors</a><ul class="auto-toc">
<li><a class="reference internal" href="#example-usage" id="id84">14.1&nbsp;&nbsp;&nbsp;Example Usage</a></li>
</ul>
</li>
<li><a class="reference internal" href="#get-extra-values" id="id85">15&nbsp;&nbsp;&nbsp;get_extra_values</a><ul class="auto-toc">
<li><a class="reference internal" href="#id14" id="id86">15.1&nbsp;&nbsp;&nbsp;Example Usage</a></li>
</ul>
</li>
<li><a class="reference internal" href="#credits" id="id87">16&nbsp;&nbsp;&nbsp;CREDITS</a></li>
<li><a class="reference internal" href="#license" id="id88">17&nbsp;&nbsp;&nbsp;LICENSE</a></li>
<li><a class="reference internal" href="#todo" id="id89">18&nbsp;&nbsp;&nbsp;TODO</a></li>
<li><a class="reference internal" href="#issues" id="id90">19&nbsp;&nbsp;&nbsp;ISSUES</a></li>
<li><a class="reference internal" href="#changelog" id="id91">20&nbsp;&nbsp;&nbsp;CHANGELOG</a><ul class="auto-toc">
<li><a class="reference internal" href="#version-4-7-2" id="id92">20.1&nbsp;&nbsp;&nbsp;2010/02/27 - Version 4.7.2</a></li>
<li><a class="reference internal" href="#version-4-7-1" id="id93">20.2&nbsp;&nbsp;&nbsp;2010/02/06 - Version 4.7.1</a></li>
<li><a class="reference internal" href="#version-4-7-0" id="id94">20.3&nbsp;&nbsp;&nbsp;2010/01/09 - Version 4.7.0</a></li>
<li><a class="reference internal" href="#version-4-6-0" id="id95">20.4&nbsp;&nbsp;&nbsp;2009/04/13 - Version 4.6.0</a></li>
<li><a class="reference internal" href="#version-4-5-3" id="id96">20.5&nbsp;&nbsp;&nbsp;2008/06/27 - Version 4.5.3</a></li>
<li><a class="reference internal" href="#version-4-5-2" id="id97">20.6&nbsp;&nbsp;&nbsp;2008/02/05 - Version 4.5.2</a></li>
<li><a class="reference internal" href="#version-4-5-1" id="id98">20.7&nbsp;&nbsp;&nbsp;2008/02/05 - Version 4.5.1</a></li>
<li><a class="reference internal" href="#version-4-5-0" id="id99">20.8&nbsp;&nbsp;&nbsp;2008/02/05 - Version 4.5.0</a></li>
<li><a class="reference internal" href="#version-4-4-0" id="id100">20.9&nbsp;&nbsp;&nbsp;2007/02/04 - Version 4.4.0</a></li>
<li><a class="reference internal" href="#version-4-3-3-alpha4" id="id101">20.10&nbsp;&nbsp;&nbsp;2006/12/17 - Version 4.3.3-alpha4</a></li>
<li><a class="reference internal" href="#version-4-3-3-alpha3" id="id102">20.11&nbsp;&nbsp;&nbsp;2006/12/17 - Version 4.3.3-alpha3</a></li>
<li><a class="reference internal" href="#version-4-3-3-alpha2" id="id103">20.12&nbsp;&nbsp;&nbsp;2006/12/09 - Version 4.3.3-alpha2</a></li>
<li><a class="reference internal" href="#version-4-3-3-alpha1" id="id104">20.13&nbsp;&nbsp;&nbsp;2006/12/09 - Version 4.3.3-alpha1</a></li>
<li><a class="reference internal" href="#version-4-3-2" id="id105">20.14&nbsp;&nbsp;&nbsp;2006/06/04 - Version 4.3.2</a></li>
<li><a class="reference internal" href="#version-4-3-1" id="id106">20.15&nbsp;&nbsp;&nbsp;2006/04/29 - Version 4.3.1</a></li>
<li><a class="reference internal" href="#version-4-3-0" id="id107">20.16&nbsp;&nbsp;&nbsp;2006/03/24 - Version 4.3.0</a></li>
<li><a class="reference internal" href="#version-4-2-0" id="id108">20.17&nbsp;&nbsp;&nbsp;2006/02/16 - Version 4.2.0</a></li>
<li><a class="reference internal" href="#version-4-1-0" id="id109">20.18&nbsp;&nbsp;&nbsp;2005/12/14 - Version 4.1.0</a></li>
<li><a class="reference internal" href="#version-4-0-2" id="id110">20.19&nbsp;&nbsp;&nbsp;2005/12/02 - Version 4.0.2</a></li>
<li><a class="reference internal" href="#version-4-0-1" id="id111">20.20&nbsp;&nbsp;&nbsp;2005/11/05 - Version 4.0.1</a></li>
<li><a class="reference internal" href="#version-4-0-0" id="id112">20.21&nbsp;&nbsp;&nbsp;2005/10/17 - Version 4.0.0</a></li>
<li><a class="reference internal" href="#version-4-0-0-beta-5" id="id113">20.22&nbsp;&nbsp;&nbsp;2005/09/09 - Version 4.0.0 beta 5</a></li>
<li><a class="reference internal" href="#version-4-0-0-beta-4" id="id114">20.23&nbsp;&nbsp;&nbsp;2005/09/07 - Version 4.0.0 beta 4</a></li>
<li><a class="reference internal" href="#version-4-0-0-beta-3" id="id115">20.24&nbsp;&nbsp;&nbsp;2005/08/28 - Version 4.0.0 beta 3</a></li>
<li><a class="reference internal" href="#version-4-0-0-beta-2" id="id116">20.25&nbsp;&nbsp;&nbsp;2005/08/25 - Version 4.0.0 beta 2</a></li>
<li><a class="reference internal" href="#version-4-0-0-beta-1" id="id117">20.26&nbsp;&nbsp;&nbsp;2005/08/21 - Version 4.0.0 beta 1</a></li>
<li><a class="reference internal" href="#version-3-0-0" id="id118">20.27&nbsp;&nbsp;&nbsp;2004/05/24 - Version 3.0.0</a></li>
<li><a class="reference internal" href="#version-2-0-0-beta" id="id119">20.28&nbsp;&nbsp;&nbsp;2004/03/14 - Version 2.0.0 beta</a></li>
<li><a class="reference internal" href="#version-1-0-5" id="id120">20.29&nbsp;&nbsp;&nbsp;2004/01/29 - Version 1.0.5</a></li>
<li><a class="reference internal" href="#origins" id="id121">20.30&nbsp;&nbsp;&nbsp;Origins</a></li>
</ul>
</li>
<li><a class="reference internal" href="#footnotes" id="id122">21&nbsp;&nbsp;&nbsp;Footnotes</a></li>
</ul>
</div>
<div class="note">
Note
The best introduction to working with ConfigObj, including the powerful configuration validation system,
is the article:
<ul class="last simple">
<li><a class="reference external" href="http://www.voidspace.org.uk/python/articles/configobj.shtml">An Introduction to ConfigObj</a></li>
</ul>
</div>
<div class="section" id="introduction">
<h1><a class="toc-backref" href="#id27">1&nbsp;&nbsp;&nbsp;Introduction</a></h1>
ConfigObj is a simple but powerful config file reader and writer: an ini
file round tripper. Its main feature is that it is very easy to use, with a
straightforward programmer's interface and a simple syntax for config files.
It has lots of other features though :
<ul>
<li>Nested sections (subsections), to any level
</li>
<li>List values
</li>
<li>Multiple line values
</li>
<li>String interpolation (substitution)
</li>
<li>Integrated with a powerful validation system
<blockquote>
<ul class="simple">
<li>including automatic type checking/conversion</li>
<li>repeated sections</li>
<li>and allowing default values</li>
</ul>
</blockquote>
</li>
<li>When writing out config files, ConfigObj preserves all comments and the order of members and sections
</li>
<li>Many useful methods and options for working with configuration files (like the 'reload' method)
</li>
<li>Full Unicode support
</li>
</ul>
For support and bug reports please use the ConfigObj <a class="reference external" href="http://lists.sourceforge.net/lists/listinfo/configobj-develop">Mailing List</a> or the issue tracker on the
<a class="reference external" href="http://code.google.com/p/configobj/">Google Code Homepage</a>.
</div>
<div class="section" id="downloading">
<h1><a class="toc-backref" href="#id28">2&nbsp;&nbsp;&nbsp;Downloading</a></h1>
The current version is 4.7.2, dated 27th February 2010. ConfigObj 4 is
stable and mature. We still expect to pick up a few bugs along the way though <a class="footnote-reference" href="#id15" id="id1">[1]</a>.
You can get ConfigObj in the following ways :
<ul>
<li><a class="reference external" href="http://www.voidspace.org.uk/downloads/configobj.py">configobj.py</a> from Voidspace
<blockquote>
ConfigObj has no external dependencies. This file is sufficient to access
all the functionality except <a class="reference internal" href="#validation">Validation</a>.
</blockquote>
</li>
<li><a class="reference external" href="http://www.voidspace.org.uk/downloads/configobj-4.7.2.zip">configobj.zip</a> from Voidspace
<blockquote>
This also contains <a class="reference external" href="http://www.voidspace.org.uk/downloads/validate.py">validate.py</a> and <a class="reference external" href="http://www.voidspace.org.uk/python/configobj.html">this document</a>.
</blockquote>
</li>
<li><a class="reference external" href="http://www.voidspace.org.uk/downloads/validate.py">validate.py</a> from Voidspace
</li>
</ul>
<div class="section" id="installing">
<h2><a class="toc-backref" href="#id29">2.1&nbsp;&nbsp;&nbsp;Installing</a></h2>
ConfigObj has a source distribution <a class="reference external" href="http://pypi.python.org/pypi/configobj/">on PyPI</a>. If you unzip
the archive you can install it with:
<pre class="literal-block">
setup.py install
</pre>
Alternatively, you can install with easy install or pip:
<pre class="literal-block">
easy_install configobj
</pre>
</div>
<div class="section" id="documentation">
<h2><a class="toc-backref" href="#id30">2.2&nbsp;&nbsp;&nbsp;Documentation</a></h2>
configobj.zip also contains <a class="reference external" href="http://www.voidspace.org.uk/python/configobj.html">this document</a>.
<ul class="simple">
<li>You can view <a class="reference external" href="http://www.voidspace.org.uk/python/configobj.html">this document</a> online at the <a class="reference external" href="http://www.voidspace.org.uk/python/configobj.html">ConfigObj Homepage</a>.</li>
</ul>
</div>
<div class="section" id="development-version">
<h2><a class="toc-backref" href="#id31">2.3&nbsp;&nbsp;&nbsp;Development Version</a></h2>
It is sometimes possible to get the latest development version of ConfigObj
from the Subversion Repository maintained on the <a class="reference external" href="http://code.google.com/p/configobj/">Google Code Homepage</a>.
</div>
</div>
<div class="section" id="configobj-in-the-real-world">
<h1><a class="toc-backref" href="#id32">3&nbsp;&nbsp;&nbsp;ConfigObj in the Real World</a></h1>
ConfigObj is widely used. Projects using it include:
<ul>
<li><a class="reference external" href="http://bazaar-ng.org">Bazaar</a>.
<blockquote>
Bazaar is a Python distributed {acro;VCS;Version Control System}.
ConfigObj is used to read <tt class="docutils literal">bazaar.conf</tt> and <tt class="docutils literal">branches.conf</tt>.
</blockquote>
</li>
<li><a class="reference external" href="http://chandler.osafoundation.org/">Chandler</a>
<blockquote>
A Python and <a class="reference external" href="http://www.wxpython.org">wxPython</a>
Personal Information Manager, being developed by the
<a class="reference external" href="http://www.osafoundation.org/">OSAFoundation</a>.
</blockquote>
</li>
<li><a class="reference external" href="http://matplotlib.sourceforge.net/">matplotlib</a>
<blockquote>
A 2D plotting library.
</blockquote>
</li>
<li><a class="reference external" href="http://ipython.scipy.org/moin/">IPython</a>
<blockquote>
IPython is an enhanced interactive Python shell. IPython uses ConfigObj in a module called 'TConfig' that combines it with enthought <a class="reference external" href="http://code.enthought.com/traits/">Traits</a>: <a class="reference external" href="http://ipython.scipy.org/ipython/ipython/browser/ipython/branches/saw/sandbox/tconfig">tconfig</a>.
</blockquote>
</li>
<li><a class="reference external" href="http://elisa.fluendo.com/">Elisa - the Fluendo Mediacenter</a>
<blockquote>
Elisa is an open source cross-platform media center solution designed to be simple for people not particularly familiar with computers.
</blockquote>
</li>
</ul>
</div>
<div class="section" id="getting-started">
<h1><a class="toc-backref" href="#id33">4&nbsp;&nbsp;&nbsp;Getting Started</a></h1>
The outstanding feature of using ConfigObj is simplicity. Most functions can be
performed with single line commands.
<div class="section" id="reading-a-config-file">
<h2><a class="toc-backref" href="#id34">4.1&nbsp;&nbsp;&nbsp;Reading a Config File</a></h2>
The normal way to read a config file, is to give ConfigObj the filename :
<div class="highlight"><pre>from configobj import ConfigObj
config = ConfigObj(filename)
</pre></div>
You can also pass the config file in as a list of lines, or a <tt class="docutils literal">StringIO</tt>
instance, so it doesn't matter where your config data comes from.
You can then access members of your config file as a dictionary. Subsections
will also be dictionaries.
<div class="highlight"><pre>from configobj import ConfigObj
config = ConfigObj(filename)
#
value1 = config[&#39;keyword1&#39;]
value2 = config[&#39;keyword2&#39;]
#
section1 = config[&#39;section1&#39;]
value3 = section1[&#39;keyword3&#39;]
value4 = section1[&#39;keyword4&#39;]
#
# you could also write
value3 = config[&#39;section1&#39;][&#39;keyword3&#39;]
value4 = config[&#39;section1&#39;][&#39;keyword4&#39;]
</pre></div>
</div>
<div class="section" id="writing-a-config-file">
<h2><a class="toc-backref" href="#id35">4.2&nbsp;&nbsp;&nbsp;Writing a Config File</a></h2>
Creating a new config file is just as easy as reading one. You can specify a
filename when you create the ConfigObj, or do it later <a class="footnote-reference" href="#id16" id="id2">[2]</a>.
If you don't set a filename, then the <tt class="docutils literal">write</tt> method will return a list of
lines instead of writing to file. See the <a class="reference internal" href="#write">write</a> method for more details.
Here we show creating an empty ConfigObj, setting a filename and some values,
and then writing to file :
<div class="highlight"><pre>from configobj import ConfigObj
config = ConfigObj()
config.filename = filename
#
config[&#39;keyword1&#39;] = value1
config[&#39;keyword2&#39;] = value2
#
config[&#39;section1&#39;] = {}
config[&#39;section1&#39;][&#39;keyword3&#39;] = value3
config[&#39;section1&#39;][&#39;keyword4&#39;] = value4
#
section2 = {
 &#39;keyword5&#39;: value5,
 &#39;keyword6&#39;: value6,
 &#39;sub-section&#39;: {
 &#39;keyword7&#39;: value7
 }
}
config[&#39;section2&#39;] = section2
#
config[&#39;section3&#39;] = {}
config[&#39;section3&#39;][&#39;keyword 8&#39;] = [value8, value9, value10]
config[&#39;section3&#39;][&#39;keyword 9&#39;] = [value11, value12, value13]
#
config.write()
</pre></div>
<div class="caution">
Caution!
Keywords and section names can only be strings <a class="footnote-reference" href="#id17" id="id3">[3]</a>. Attempting to set
anything else will raise a <tt class="docutils literal">ValueError</tt>.
See <a class="reference internal" href="#string-interpolation-and-list-values">String Interpolation and List Values</a> for an important note on
using lists in combination with <a class="reference internal" href="#string-interpolation">String Interpolation</a>.
</div>
</div>
<div class="section" id="config-files">
<h2><a class="toc-backref" href="#id36">4.3&nbsp;&nbsp;&nbsp;Config Files</a></h2>
The config files that ConfigObj will read and write are based on the 'INI'
format. This means it will read and write files created for <tt class="docutils literal">ConfigParser</tt>
<a class="footnote-reference" href="#id18" id="id4">[4]</a>.
Keywords and values are separated by an <tt class="docutils literal">'='</tt>, and section markers are
between square brackets. Keywords, values, and section names can be surrounded
by single or double quotes. Indentation is not significant, but can be
preserved.
Subsections are indicated by repeating the square brackets in the section
marker. You nest levels by using more brackets.
You can have list values by separating items with a comma, and values spanning
multiple lines by using triple quotes (single or double).
For full details on all these see <a class="reference internal" href="#the-config-file-format">the config file format</a>. Here's an example
to illustrate:
<pre class="literal-block">
# This is the 'initial_comment'
# Which may be several lines
keyword1 = value1
'keyword 2' = 'value 2'

[ &quot;section 1&quot; ]
# This comment goes with keyword 3
keyword 3 = value 3
'keyword 4' = value4, value 5, 'value 6'

[[ sub-section ]]    # an inline comment
    # sub-section is inside &quot;section 1&quot;
    'keyword 5' = 'value 7'
    'keyword 6' = '''A multiline value,
that spans more than one line :-)
The line breaks are included in the value.'''

[[[ sub-sub-section ]]]
        # sub-sub-section is *in* 'sub-section'
        # which is in 'section 1'
        'keyword 7' = 'value 8'

[section 2] # an inline comment
keyword8 = &quot;value 9&quot;
keyword9 = value10 # an inline comment
# The 'final_comment'
# Which also may be several lines
</pre>
</div>
</div>
<div class="section" id="configobj-specifications">
<h1><a class="toc-backref" href="#id37">5&nbsp;&nbsp;&nbsp;ConfigObj specifications</a></h1>
<div class="highlight"><pre>config = ConfigObj(infile=None, options=None, configspec=None, encoding=None,
 interpolation=True, raise_errors=False, list_values=True,
 create_empty=False, file_error=False, stringify=True,
 indent_type=None, default_encoding=None, unrepr=False,
 write_empty_values=False, _inspec=False)
</pre></div>
Many of the keyword arguments are available as attributes after the config file has been
parsed.
<div class="note">
Note
New in ConfigObj 4.7.0: Instantiating ConfigObj with
an <tt class="docutils literal">options</tt> dictionary is now deprecated. To modify code that used to
do this simply unpack the dictionary in the constructor call:
<div class="last"><div class="highlight"><pre>config = ConfigObj(filename, **options)
</pre></div>
</div></div>
ConfigObj takes the following arguments (with the default values shown) :
<ul>
<li>infile: <tt class="docutils literal">None</tt>
<blockquote>
You don't need to specify an infile. If you omit it, an empty ConfigObj will be
created. <tt class="docutils literal">infile</tt> can be :
<ul class="simple">
<li>Nothing. In which case the <tt class="docutils literal">filename</tt> attribute of your ConfigObj will be
<tt class="docutils literal">None</tt>. You can set a filename at any time.</li>
<li>A filename. What happens if the file doesn't already exist is determined by
the options <tt class="docutils literal">file_error</tt> and <tt class="docutils literal">create_empty</tt>. The filename will be
preserved as the <tt class="docutils literal">filename</tt> attribute. This can be changed at any time.</li>
<li>A list of lines. Any trailing newlines will be removed from the lines. The
<tt class="docutils literal">filename</tt> attribute of your ConfigObj will be <tt class="docutils literal">None</tt>.</li>
<li>A <tt class="docutils literal">StringIO</tt> instance or file object, or any object with a <tt class="docutils literal">read</tt> method.
The <tt class="docutils literal">filename</tt> attribute of your ConfigObj will be <tt class="docutils literal">None</tt> <a class="footnote-reference" href="#id19" id="id5">[5]</a>.</li>
<li>A dictionary. You can initialise a ConfigObj from a dictionary <a class="footnote-reference" href="#id20" id="id6">[6]</a>. The
<tt class="docutils literal">filename</tt> attribute of your ConfigObj will be <tt class="docutils literal">None</tt>. All keys must be
strings. In this case, the order of values and sections is arbitrary.</li>
</ul>
</blockquote>
</li>
<li>'raise_errors': <tt class="docutils literal">False</tt>
<blockquote>
When parsing, it is possible that the config file will be badly formed. The
default is to parse the whole file and raise a single error at the end. You
can set <tt class="docutils literal">raise_errors = True</tt> to have errors raised immediately. See the
<a class="reference internal" href="#exceptions">exceptions</a> section for more details.
Altering this value after initial parsing has no effect.
</blockquote>
</li>
<li>'list_values': <tt class="docutils literal">True</tt>
<blockquote>
If <tt class="docutils literal">True</tt> (the default) then list values are possible. If <tt class="docutils literal">False</tt>, the
values are not parsed for lists.
If <tt class="docutils literal">list_values = False</tt> then single line values are not quoted or
unquoted when reading and writing.
Changing this value affects whether single line values will be quoted or
not when writing.
</blockquote>
</li>
<li>'create_empty': <tt class="docutils literal">False</tt>
<blockquote>
If this value is <tt class="docutils literal">True</tt> and the file specified by <tt class="docutils literal">infile</tt> doesn't
exist, ConfigObj will create an empty file. This can be a useful test that
the filename makes sense: an impossible filename will cause an error.
Altering this value after initial parsing has no effect.
</blockquote>
</li>
<li>'file_error': <tt class="docutils literal">False</tt>
<blockquote>
If this value is <tt class="docutils literal">True</tt> and the file specified by <tt class="docutils literal">infile</tt> doesn't
exist, ConfigObj will raise an <tt class="docutils literal">IOError</tt>.
Altering this value after initial parsing has no effect.
</blockquote>
</li>
<li>'interpolation': <tt class="docutils literal">True</tt>
<blockquote>
Whether string interpolation is switched on or not. It is on (<tt class="docutils literal">True</tt>) by
default.
You can set this attribute to change whether string interpolation is done
when values are fetched. See the <a class="reference internal" href="#string-interpolation">String Interpolation</a> section for more details.
New in ConfigObj 4.7.0: Interpolation will also be done in list values.
</blockquote>
</li>
<li>'configspec': <tt class="docutils literal">None</tt>
<blockquote>
If you want to use the validation system, you supply a configspec. This is
effectively a type of config file that specifies a check for each member.
This check can be used to do type conversion as well as check that the
value is within your required parameters.
You provide a configspec in the same way as you do the initial file: a
filename, or list of lines, etc. See the <a class="reference internal" href="#validation">validation</a> section for full
details on how to use the system.
When parsed, every section has a <tt class="docutils literal">configspec</tt> with a dictionary of
configspec checks for that section.
</blockquote>
</li>
<li>'stringify': <tt class="docutils literal">True</tt>
<blockquote>
If you use the validation scheme, it can do type checking and conversion
for you. This means you may want to set members to integers, or other
non-string values.
If 'stringify' is set to <tt class="docutils literal">True</tt> (default) then non-string values will
be converted to strings when you write the config file. The <a class="reference internal" href="#validation">validation</a>
process converts values from strings to the required type.
If 'stringify' is set to <tt class="docutils literal">False</tt>, attempting to set a member to a
non-string value <a class="footnote-reference" href="#id21" id="id7">[7]</a> will raise a <tt class="docutils literal">TypeError</tt> (no type conversion is
done by validation).
</blockquote>
</li>
<li>'indent_type': <tt class="docutils literal">'&nbsp;&nbsp;&nbsp; '</tt>
<blockquote>
Indentation is not significant; it can however be present in the input and
output config. Any combination of tabs and spaces may be used: the string
will be repeated for each level of indentation. Typical values are: <tt class="docutils literal">''</tt>
(no indentation), <tt class="docutils literal">'&nbsp;&nbsp;&nbsp; '</tt> (indentation with four spaces, the default),
<tt class="docutils literal">'\t'</tt> (indentation with one tab).
If this option is not specified, and the ConfigObj is initialised with a
dictionary, the indentation used in the output is the default one, that is,
four spaces.
If this option is not specified, and the ConfigObj is initialised with a
list of lines or a file, the indentation used in the first indented line is
selected and used in all output lines. If no input line is indented, no
output line will be either.
If this option is specified, the option value is used in the output
config, overriding the type of indentation in the input config (if any).
</blockquote>
</li>
<li>'encoding': <tt class="docutils literal">None</tt>
<blockquote>
By default ConfigObj does not decode the file/strings you pass it into
Unicode <a class="footnote-reference" href="#id22" id="id8">[8]</a>. If you want your config file as Unicode (keys and members)
you need to provide an encoding to decode the file with. This encoding will
also be used to encode the config file when writing.
You can change the encoding attribute at any time.
Any characters in your strings that can't be encoded with the specified
encoding will raise a <tt class="docutils literal">UnicodeEncodeError</tt>.
<div class="note">
Note
<tt class="docutils literal">UTF16</tt> encoded files will automatically be detected and decoded,
even if <tt class="docutils literal">encoding</tt> is <tt class="docutils literal">None</tt>.
This is because it is a 16-bit encoding, and ConfigObj will mangle it
(split characters on byte boundaries) if it parses it without decoding.
</div>
</blockquote>
</li>
<li>'default_encoding': <tt class="docutils literal">None</tt>
<blockquote>
When using the <tt class="docutils literal">write</tt> method, ConfigObj uses the <tt class="docutils literal">encoding</tt>
attribute to encode the Unicode strings. If any members (or keys) have
been set as byte strings instead of Unicode, these must first be decoded
to Unicode before outputting in the specified encoding.
<tt class="docutils literal">default_encoding</tt>, if specified, is the encoding used to decode byte
strings in the ConfigObj before writing. If this is <tt class="docutils literal">None</tt>, then
the Python default encoding (<tt class="docutils literal">sys.defaultencoding</tt> - usually ASCII) is
used.
For most Western European users, a value of <tt class="docutils literal">latin-1</tt> is sensible.
<tt class="docutils literal">default_encoding</tt> is only used if an <tt class="docutils literal">encoding</tt> is specified.
Any characters in byte-strings that can't be decoded using the
<tt class="docutils literal">default_encoding</tt> will raise a <tt class="docutils literal">UnicodeDecodeError</tt>.
</blockquote>
</li>
<li>'unrepr': <tt class="docutils literal">False</tt>
<blockquote>
The <tt class="docutils literal">unrepr</tt> option reads and writes files in a different mode. This
allows you to store and retrieve the basic Python data-types using config
files.
This uses Python syntax for lists and quoting. See <a class="reference internal" href="#unrepr-mode">unrepr mode</a> for the
full details.
</blockquote>
</li>
<li>'write_empty_values': <tt class="docutils literal">False</tt>
<blockquote>
If <tt class="docutils literal">write_empty_values</tt> is <tt class="docutils literal">True</tt>, empty strings are written as
empty values. See <a class="reference internal" href="#empty-values">Empty Values</a> for more details.
</blockquote>
</li>
<li>'_inspec': <tt class="docutils literal">False</tt>
<blockquote>
Used internally by ConfigObj when parsing configspec files. If you are
creating a ConfigObj instance from a configspec file you must pass True
for this argument as well as <tt class="docutils literal">list_values=False</tt>.
</blockquote>
</li>
</ul>
<div class="section" id="methods">
<h2><a class="toc-backref" href="#id38">5.1&nbsp;&nbsp;&nbsp;Methods</a></h2>
The ConfigObj is a subclass of an object called <tt class="docutils literal">Section</tt>, which is itself a
subclass of <tt class="docutils literal">dict</tt>, the builtin dictionary type. This means it also has
all the normal dictionary methods.
In addition, the following <a class="reference internal" href="#section-methods">Section Methods</a> may be useful :
<ul class="simple">
<li>'restore_default'</li>
<li>'restore_defaults'</li>
<li>'walk'</li>
<li>'merge'</li>
<li>'dict'</li>
<li>'as_bool'</li>
<li>'as_float'</li>
<li>'as_int'</li>
<li>'as_list'</li>
</ul>
Read about <a class="reference internal" href="#sections">Sections</a> for details of all the methods.
<div class="hint">
Hint
The merge method of sections is a recursive update.
You can use this to merge sections, or even whole ConfigObjs, into each
other.
You would typically use this to create a default ConfigObj and then merge
in user settings. This way users only need to specify values that are
different from the default. You can use configspecs and validation to
achieve the same thing of course.
</div>
The public methods available on ConfigObj are :
<ul class="simple">
<li>'write'</li>
<li>'validate'</li>
<li>'reset'</li>
<li>'reload'</li>
</ul>
<div class="section" id="write">
<h3><a class="toc-backref" href="#id39">5.1.1&nbsp;&nbsp;&nbsp;write</a></h3>
<div class="highlight"><pre>write(file_object=None)
</pre></div>
This method writes the current ConfigObj and takes a single, optional argument
<a class="footnote-reference" href="#id23" id="id9">[9]</a>.
If you pass in a file like object to the <tt class="docutils literal">write</tt> method, the config file will
be written to this. (The only method of this object that is used is its
<tt class="docutils literal">write</tt> method, so a <tt class="docutils literal">StringIO</tt> instance, or any other file like object
will work.)
Otherwise, the behaviour of this method depends on the <tt class="docutils literal">filename</tt> attribute
of the ConfigObj.
<dl class="docutils">
<dt><tt class="docutils literal">filename</tt></dt>
<dd>ConfigObj will write the configuration to the file specified.</dd>
<dt><tt class="docutils literal">None</tt></dt>
<dd><tt class="docutils literal">write</tt> returns a list of lines. (Not <tt class="docutils literal">'\n'</tt> terminated)</dd>
</dl>
First the 'initial_comment' is written, then the config file, followed by the
'final_comment'. Comment lines and inline comments are written with each
key/value.
</div>
<div class="section" id="validate">
<h3><a class="toc-backref" href="#id40">5.1.2&nbsp;&nbsp;&nbsp;validate</a></h3>
<div class="highlight"><pre>validate(validator, preserve_errors=False, copy=False)
</pre></div>
<div class="highlight"><pre># filename is the config file
# filename2 is the configspec
# (which could also be hardcoded into your program)
config = ConfigObj(filename, configspec=filename2)
#
from validate import Validator
val = Validator()
test = config.validate(val)
if test == True:
 print &#39;Succeeded.&#39;
</pre></div>
The validate method uses the <a class="reference external" href="http://www.voidspace.org.uk/python/validate.html">validate</a> module to do the
validation.
This method validates the ConfigObj against the configspec. By doing type
conversion as well it can abstract away the config file altogether and present
the config data to your application (in the types it expects it to be).
If the <tt class="docutils literal">configspec</tt> attribute of the ConfigObj is <tt class="docutils literal">None</tt>, it raises a
<tt class="docutils literal">ValueError</tt>.
If the <a class="reference internal" href="#stringify">stringify</a> attribute is set, this process will convert values to the
type defined in the configspec.
The validate method uses checks specified in the configspec and defined in the
<tt class="docutils literal">Validator</tt> object. It is very easy to extend.
The configspec looks like the config file, but instead of the value, you
specify the check (and any default value). See the <a class="reference internal" href="#validation">validation</a> section for
details.
<div class="hint">
Hint
The system of configspecs can seem confusing at first, but is actually
quite simple and powerful. The best guide to them is this article on
ConfigObj:
<ul class="last simple">
<li><a class="reference external" href="http://www.voidspace.org.uk/python/articles/configobj.shtml">An Introduction to ConfigObj</a></li>
</ul>
</div>
The <tt class="docutils literal">copy</tt> parameter fills in missing values from the configspec (default
values), without marking the values as defaults. It also causes comments to
be copied from the configspec into the config file. This allows you to use a
configspec to create default config files. (Normally default values aren't
written out by the <tt class="docutils literal">write</tt> method.)
As of ConfigObj 4.3.0 you can also pass in a ConfigObj instance as your
configspec. This is especially useful if you need to specify the encoding of
your configspec file. When you read your configspec file, you must specify
<tt class="docutils literal">list_values=False</tt>. If you need to support hashes inside the configspec
values then you must also pass in <tt class="docutils literal">_inspec=True</tt>. This is because configspec
files actually use a different syntax to config files and inline comment support
must be switched off to correctly read configspec files with hashes in the values.
<div class="highlight"><pre>from configobj import ConfigObj
configspec = ConfigObj(configspecfilename, encoding=&#39;UTF8&#39;,
 list_values=False, _inspec=True)
config = ConfigObj(filename, configspec=configspec)
</pre></div>
<div class="section" id="return-value">
<h4><a class="toc-backref" href="#id41">5.1.2.1&nbsp;&nbsp;&nbsp;Return Value</a></h4>
By default, the validate method either returns <tt class="docutils literal">True</tt> (everything passed)
or a dictionary of <tt class="docutils literal">True</tt> / <tt class="docutils literal">False</tt> representing pass/fail. The dictionary
follows the structure of the ConfigObj.
If a whole section passes then it is replaced with the value <tt class="docutils literal">True</tt>. If a
whole section fails, then it is replaced with the value <tt class="docutils literal">False</tt>.
If a value is missing, and there is no default in the check, then the check
automatically fails.
The <tt class="docutils literal">validate</tt> method takes an optional keyword argument <tt class="docutils literal">preserve_errors</tt>.
If you set this to <tt class="docutils literal">True</tt>, instead of getting <tt class="docutils literal">False</tt> for failed checks you
get the actual error object from the validate module. This usually contains
useful information about why the check failed.
See the <a class="reference internal" href="#flatten-errors">flatten_errors</a> function for how to turn your results dictionary into
a useful list of error messages.
Even if <tt class="docutils literal">preserve_errors</tt> is <tt class="docutils literal">True</tt>, missing keys or sections will still be
represented by a <tt class="docutils literal">False</tt> in the results dictionary.
</div>
<div class="section" id="mentioning-default-values">
<h4><a class="toc-backref" href="#id42">5.1.2.2&nbsp;&nbsp;&nbsp;Mentioning Default Values</a></h4>
In the check in your configspec, you can specify a default to be used - by
using the <tt class="docutils literal">default</tt> keyword. E.g.
<pre class="literal-block">
key1 = integer(0, 30, default=15)
key2 = integer(default=15)
key3 = boolean(default=True)
key4 = option('Hello', 'Goodbye', 'Not Today', default='Not Today')
</pre>
If the configspec check supplies a default and the value is missing in the
config, then the default will be set in your ConfigObj. (It is still passed to
the <tt class="docutils literal">Validator</tt> so that type conversion can be done: this means the default
value must still pass the check.)
ConfigObj keeps a record of which values come from defaults, using the
<tt class="docutils literal">defaults</tt> attribute of <a class="reference internal" href="#sections">sections</a>. Any key in this list isn't written out by
the <tt class="docutils literal">write</tt> method. If a key is set from outside (even to the same value)
then it is removed from the <tt class="docutils literal">defaults</tt> list.
<!-- note:

Even if all the keys in a section are in the defaults list, the section
marker is still written out. -->
There is additionally a special case default value of <tt class="docutils literal">None</tt>. If you set the
default value to <tt class="docutils literal">None</tt> and the value is missing, the value will always be
set to <tt class="docutils literal">None</tt>. As the other checks don't return <tt class="docutils literal">None</tt> (unless you
implement your own that do), you can tell that this value came from a default
value (and was missing from the config file). It allows an easy way of
implementing optional values. Simply check (and ignore) members that are set
to <tt class="docutils literal">None</tt>.
<div class="note">
Note
If <a class="reference internal" href="#stringify">stringify</a> is <tt class="docutils literal">False</tt> then <tt class="docutils literal">default=None</tt> returns <tt class="docutils literal">''</tt> instead of
<tt class="docutils literal">None</tt>. This is because setting a value to a non-string raises an error
if stringify is unset.
</div>
The default value can be a list. See <a class="reference internal" href="#id13">List Values</a> for the way to do this.
Writing invalid default values is a guaranteed way of confusing your users.
Default values must pass the check.
</div>
<div class="section" id="mentioning-repeated-sections-and-values">
<h4><a class="toc-backref" href="#id43">5.1.2.3&nbsp;&nbsp;&nbsp;Mentioning Repeated Sections and Values</a></h4>
In the configspec it is possible to cause every sub-section in a section to
be validated using the same configspec. You do this with a section in the
configspec called <tt class="docutils literal">__many__</tt>. Every sub-section in that section has the
<tt class="docutils literal">__many__</tt> configspec applied to it (without you having to explicitly name
them in advance).
Your <tt class="docutils literal">__many__</tt> section can have nested subsections, which can also include
<tt class="docutils literal">__many__</tt> type sections.
You can also specify that all values should be validated using the same configspec,
by having a member with the name <tt class="docutils literal">__many__</tt>. If you want to use repeated values
along with repeated sections then you can call one of them <tt class="docutils literal">___many___</tt> (triple
underscores).
Sections with repeated sections or values can also have specifically named sub-sections
or values. The <tt class="docutils literal">__many__</tt> configspec will only be used to validate entries that don't
have an explicit configspec.
See <a class="reference internal" href="#repeated-sections">Repeated Sections</a> for examples.
</div>
<div class="section" id="mentioning-simpleval">
<h4><a class="toc-backref" href="#id44">5.1.2.4&nbsp;&nbsp;&nbsp;Mentioning SimpleVal</a></h4>
If you just want to check if all members are present, then you can use the
<tt class="docutils literal">SimpleVal</tt> object that comes with ConfigObj. It only fails members if they
are missing.
Write a configspec that has all the members you want to check for, but set
every section to <tt class="docutils literal">''</tt>.
<div class="highlight"><pre>val = SimpleVal()
test = config.validate(val)
if test is True:
 print &#39;Succeeded.&#39;
</pre></div>
</div>
<div class="section" id="mentioning-copy-mode">
<h4><a class="toc-backref" href="#id45">5.1.2.5&nbsp;&nbsp;&nbsp;Mentioning copy Mode</a></h4>
As discussed in <a class="reference internal" href="#mentioning-default-values">Mentioning Default Values</a>, you can use a configspec to
supply default values. These are marked in the ConfigObj instance as defaults,
and not written out by the <tt class="docutils literal">write</tt> mode. This means that your users only
need to supply values that are different from the defaults.
This can be inconvenient if you do want to write out the default values,
for example to write out a default config file.
If you set <tt class="docutils literal">copy=True</tt> when you call validate, then no values are marked as
defaults. In addition, all comments from the configspec are copied into
your ConfigObj instance. You can then call <tt class="docutils literal">write</tt> to create your config
file.
There is a limitation with this. In order to allow <a class="reference internal" href="#string-interpolation">String Interpolation</a> to work
within configspecs, <tt class="docutils literal">DEFAULT</tt> sections are not processed by
validation; even in copy mode.
</div>
</div>
<div class="section" id="reload">
<h3><a class="toc-backref" href="#id46">5.1.3&nbsp;&nbsp;&nbsp;reload</a></h3>
If a ConfigObj instance was loaded from the filesystem, then this method will reload it. It
will also reuse any configspec you supplied at instantiation (including reloading it from
the filesystem if you passed it in as a filename).
If the ConfigObj does not have a filename attribute pointing to a file, then a <tt class="docutils literal">ReloadError</tt>
will be raised.
</div>
<div class="section" id="reset">
<h3><a class="toc-backref" href="#id47">5.1.4&nbsp;&nbsp;&nbsp;reset</a></h3>
This method takes no arguments and doesn't return anything. It restores a ConfigObj
instance to a freshly created state.
</div>
</div>
<div class="section" id="attributes">
<h2><a class="toc-backref" href="#id48">5.2&nbsp;&nbsp;&nbsp;Attributes</a></h2>
A ConfigObj has the following attributes :
<ul class="simple">
<li>indent_type</li>
<li>interpolation</li>
<li>stringify</li>
<li>BOM</li>
<li>initial_comment</li>
<li>final_comment</li>
<li>list_values</li>
<li>encoding</li>
<li>default_encoding</li>
<li>unrepr</li>
<li>write_empty_values</li>
<li>newlines</li>
</ul>
<div class="note">
Note
This doesn't include comments, inline_comments, defaults, or
configspec. These are actually attributes of <a class="reference internal" href="#sections">Sections</a>.
</div>
It also has the following attributes as a result of parsing. They correspond to
options when the ConfigObj was created, but changing them has no effect.
<ul class="simple">
<li>raise_errors</li>
<li>create_empty</li>
<li>file_error</li>
</ul>
<div class="section" id="interpolation">
<h3><a class="toc-backref" href="#id49">5.2.1&nbsp;&nbsp;&nbsp;interpolation</a></h3>
ConfigObj can perform string interpolation in a similar way to
<tt class="docutils literal">ConfigParser</tt>. See the <a class="reference internal" href="#string-interpolation">String Interpolation</a> section for full details.
If <tt class="docutils literal">interpolation</tt> is set to <tt class="docutils literal">False</tt>, then interpolation is not done when
you fetch values.
</div>
<div class="section" id="stringify">
<h3><a class="toc-backref" href="#id50">5.2.2&nbsp;&nbsp;&nbsp;stringify</a></h3>
If this attribute is set (<tt class="docutils literal">True</tt>) then the <a class="reference internal" href="#validate">validate</a> method changes the
values in the ConfigObj. These are turned back into strings when <a class="reference internal" href="#write">write</a> is
called.
If stringify is unset (<tt class="docutils literal">False</tt>) then attempting to set a value to a non
string (or a list of strings) will raise a <tt class="docutils literal">TypeError</tt>.
</div>
<div class="section" id="bom">
<h3><a class="toc-backref" href="#id51">5.2.3&nbsp;&nbsp;&nbsp;BOM</a></h3>
If the initial config file started with the UTF8 Unicode signature (known
slightly incorrectly as the BOM - Byte Order Mark), or the UTF16 BOM, then
this attribute is set to <tt class="docutils literal">True</tt>. Otherwise it is <tt class="docutils literal">False</tt>.
If it is set to <tt class="docutils literal">True</tt> when <tt class="docutils literal">write</tt> is called then, if <tt class="docutils literal">encoding</tt> is set
to <tt class="docutils literal">None</tt> or to <tt class="docutils literal">utf_8</tt> (and variants) a UTF BOM will be written.
For UTF16 encodings, a BOM is always written.
</div>
<div class="section" id="initial-comment">
<h3><a class="toc-backref" href="#id52">5.2.4&nbsp;&nbsp;&nbsp;initial_comment</a></h3>
This is a list of lines. If the ConfigObj is created from an existing file, it
will contain any lines of comments before the start of the members.
If you create a new ConfigObj, this will be an empty list.
The write method puts these lines before it starts writing out the members.
</div>
<div class="section" id="final-comment">
<h3><a class="toc-backref" href="#id53">5.2.5&nbsp;&nbsp;&nbsp;final_comment</a></h3>
This is a list of lines. If the ConfigObj is created from an existing file, it
will contain any lines of comments after the last member.
If you create a new ConfigObj, this will be an empty list.
The <tt class="docutils literal">write</tt> method puts these lines after it finishes writing out the
members.
</div>
<div class="section" id="list-values">
<h3><a class="toc-backref" href="#id54">5.2.6&nbsp;&nbsp;&nbsp;list_values</a></h3>
This attribute is <tt class="docutils literal">True</tt> or <tt class="docutils literal">False</tt>. If set to <tt class="docutils literal">False</tt> then values are
not parsed for list values. In addition single line values are not unquoted.
This allows you to do your own parsing of values. It exists primarily to
support the reading of the <a class="reference internal" href="#configspec">configspec</a> - but has other use cases.
For example you could use the <tt class="docutils literal">LineParser</tt> from the
<a class="reference external" href="http://www.voidspace.org.uk/python/listquote.html#lineparser">listquote module</a>
to read values for nested lists.
Single line values aren't quoted when writing - but multiline values are
handled as normal.
<div class="caution">
Caution!
Because values aren't quoted, leading or trailing whitespace can be lost. This behaviour was changed in version 4.0.1. Prior to this, single line values might have been quoted; even with <tt class="docutils literal">list_values=False</tt>. This means that files written by earlier versions of ConfigObj could now be incompatible and need the quotes removing by hand.
</div>
</div>
<div class="section" id="encoding">
<h3><a class="toc-backref" href="#id55">5.2.7&nbsp;&nbsp;&nbsp;encoding</a></h3>
This is the encoding used to encode the output, when you call <tt class="docutils literal">write</tt>. It
must be a valid encoding <a class="reference external" href="http://docs.python.org/lib/standard-encodings.html">recognised by Python</a>.
If this value is <tt class="docutils literal">None</tt> then no encoding is done when <tt class="docutils literal">write</tt> is called.
</div>
<div class="section" id="default-encoding">
<h3><a class="toc-backref" href="#id56">5.2.8&nbsp;&nbsp;&nbsp;default_encoding</a></h3>
If encoding is set, any byte-strings in your ConfigObj instance (keys or
members) will first be decoded to Unicode using the encoding specified by the
<tt class="docutils literal">default_encoding</tt> attribute. This ensures that the output is in the encoding
specified.
If this value is <tt class="docutils literal">None</tt> then <tt class="docutils literal">sys.defaultencoding</tt> is used instead.
</div>
<div class="section" id="unrepr">
<h3><a class="toc-backref" href="#id57">5.2.9&nbsp;&nbsp;&nbsp;unrepr</a></h3>
Another boolean value. If this is set, then <tt class="docutils literal">repr(value)</tt> is used to write
values. This writes values in a slightly different way to the normal ConfigObj
file syntax.
This preserves basic Python data-types when read back in. See <a class="reference internal" href="#unrepr-mode">unrepr mode</a>
for more details.
</div>
<div class="section" id="write-empty-values">
<h3><a class="toc-backref" href="#id58">5.2.10&nbsp;&nbsp;&nbsp;write_empty_values</a></h3>
Also boolean. If set, values that are an empty string (<tt class="docutils literal">''</tt>) are written as
empty values. See <a class="reference internal" href="#empty-values">Empty Values</a> for more details.
</div>
<div class="section" id="newlines">
<h3><a class="toc-backref" href="#id59">5.2.11&nbsp;&nbsp;&nbsp;newlines</a></h3>
When a config file is read, ConfigObj records the type of newline separators in the
file and uses this separator when writing. It defaults to <tt class="docutils literal">None</tt>, and ConfigObj
uses the system default (<tt class="docutils literal">os.sep</tt>) if write is called without newlines having
been set.
</div>
</div>
</div>
<div class="section" id="the-config-file-format">
<h1><a class="toc-backref" href="#id60">6&nbsp;&nbsp;&nbsp;The Config File Format</a></h1>
You saw an example config file in the <a class="reference internal" href="#config-files">Config Files</a> section. Here is a fuller
specification of the config files used and created by ConfigObj.
The basic pattern for keywords is:
<pre class="literal-block">
# comment line
# comment line
keyword = value # inline comment
</pre>
Both keyword and value can optionally be surrounded in quotes. The equals sign
is the only valid divider.
Values can have comments on the lines above them, and an inline comment after
them. This, of course, is optional. See the <a class="reference internal" href="#comments">comments</a> section for details.
If a keyword or value starts or ends with whitespace, or contains a quote mark
or comma, then it should be surrounded by quotes. Quotes are not necessary if
whitespace is surrounded by non-whitespace.
Values can also be lists. Lists are comma separated. You indicate a single
member list by a trailing comma. An empty list is shown by a single comma:
<pre class="literal-block">
keyword1 = value1, value2, value3
keyword2 = value1, # a single member list
keyword3 = , # an empty list
</pre>
Values that contain line breaks (multi-line values) can be surrounded by triple
quotes. These can also be used if a value contains both types of quotes. List
members cannot be surrounded by triple quotes:
<pre class="literal-block">
keyword1 = ''' A multi line value
on several
lines''' # with a comment
keyword2 = '''I won't be &quot;afraid&quot;.'''
#
keyword3 = &quot;&quot;&quot; A multi line value
on several
lines&quot;&quot;&quot; # with a comment
keyword4 = &quot;&quot;&quot;I won't be &quot;afraid&quot;.&quot;&quot;&quot;
</pre>
<div class="warning">
Warning
There is no way of safely quoting values that contain both types of triple
quotes.
</div>
A line that starts with a '#', possibly preceded by whitespace, is a comment.
New sections are indicated by a section marker line. That is the section name
in square brackets. Whitespace around the section name is ignored. The name can
be quoted with single or double quotes. The marker can have comments before it
and an inline comment after it:
<pre class="literal-block">
# The First Section
[ section name 1 ] # first section
keyword1 = value1

# The Second Section
[ &quot;section name 2&quot; ] # second section
keyword2 = value2
</pre>
Any subsections (sections that are inside the current section) are
designated by repeating the square brackets before and after the section name.
The number of square brackets represents the nesting level of the sub-section.
Square brackets may be separated by whitespace; such whitespace, however, will
not be present in the output config written by the <tt class="docutils literal">write</tt> method.
Indentation is not significant, but can be preserved. See the description of
the <tt class="docutils literal">indent_type</tt> option, in the <a class="reference internal" href="#configobj-specifications">ConfigObj specifications</a> chapter, for the
details.
A NestingError will be raised if the number of the opening and the closing
brackets in a section marker is not the same, or if a sub-section's nesting
level is greater than the nesting level of it parent plus one.
In the outer section, single values can only appear before any sub-section.
Otherwise they will belong to the sub-section immediately before them:
<pre class="literal-block">
# initial comment
keyword1 = value1
keyword2 = value2

[section 1]
keyword1 = value1
keyword2 = value2

[[sub-section]]
    # this is in section 1
    keyword1 = value1
    keyword2 = value2

[[[nested section]]]
        # this is in sub section
        keyword1 = value1
        keyword2 = value2

[[sub-section2]]
    # this is in section 1 again
    keyword1 = value1
    keyword2 = value2

[[sub-section3]]
# this is also in section 1, indentation is misleading here
keyword1 = value1
keyword2 = value2

# final comment
</pre>
When parsed, the above config file produces the following data structure:
<div class="highlight"><pre>ConfigObj({
 &#39;keyword1&#39;: &#39;value1&#39;,
 &#39;keyword2&#39;: &#39;value2&#39;,
 &#39;section 1&#39;: {
 &#39;keyword1&#39;: &#39;value1&#39;,
 &#39;keyword2&#39;: &#39;value2&#39;,
 &#39;sub-section&#39;: {
 &#39;keyword1&#39;: &#39;value1&#39;,
 &#39;keyword2&#39;: &#39;value2&#39;,
 &#39;nested section&#39;: {
 &#39;keyword1&#39;: &#39;value1&#39;,
 &#39;keyword2&#39;: &#39;value2&#39;,
 },
 },
 &#39;sub-section2&#39;: {
 &#39;keyword1&#39;: &#39;value1&#39;,
 &#39;keyword2&#39;: &#39;value2&#39;,
 },
 &#39;sub-section3&#39;: {
 &#39;keyword1&#39;: &#39;value1&#39;,
 &#39;keyword2&#39;: &#39;value2&#39;,
 },
 },
})
</pre></div>
Sections are ordered: note how the structure of the resulting ConfigObj is in
the same order as the original file.
<div class="note">
Note
In ConfigObj 4.3.0 empty values became valid syntax. They are read as the
empty string. There is also an option/attribute (<tt class="docutils literal">write_empty_values</tt>) to
allow the writing of these.
This is mainly to support 'legacy' config files, written from other
applications. This is documented under <a class="reference internal" href="#empty-values">Empty Values</a>.
<a class="reference internal" href="#unrepr-mode">unrepr mode</a> introduces another syntax variation, used for storing
basic Python datatypes in config files.
</div>
</div>
<div class="section" id="sections">
<h1><a class="toc-backref" href="#id61">7&nbsp;&nbsp;&nbsp;Sections</a></h1>
Every section in a ConfigObj has certain properties. The ConfigObj itself also
has these properties, because it too is a section (sometimes called the root
section).
<tt class="docutils literal">Section</tt> is a subclass of the standard new-class dictionary, therefore it
has all the methods of a normal dictionary. This means you can <tt class="docutils literal">update</tt>
and <tt class="docutils literal">clear</tt> sections.
<div class="note">
Note
You create a new section by assigning a member to be a dictionary.
The new <tt class="docutils literal">Section</tt> is created from the dictionary, but isn't the same
thing as the dictionary. (So references to the dictionary you use to create
the section aren't references to the new section).
Note the following.
<div class="highlight"><pre>config = ConfigObj()
vals = {&#39;key1&#39;: &#39;value 1&#39;,
 &#39;key2&#39;: &#39;value 2&#39;
 }
config[&#39;vals&#39;] = vals
config[&#39;vals&#39;] == vals
True
config[&#39;vals&#39;] is vals
False
</pre></div>
If you now change <tt class="docutils literal">vals</tt>, the changes won't be reflected in <tt class="docutils literal">config['vals']</tt>.
</div>
A section is ordered, following its <tt class="docutils literal">scalars</tt> and <tt class="docutils literal">sections</tt>
attributes documented below. This means that the following dictionary
attributes return their results in order.
<ul>
<li>'__iter__'
<blockquote>
More commonly known as <tt class="docutils literal">for member in section:</tt>.
</blockquote>
</li>
<li>'__repr__' and '__str__'
<blockquote>
Any time you print or display the ConfigObj.
</blockquote>
</li>
<li>'items'
</li>
<li>'iteritems'
</li>
<li>'iterkeys'
</li>
<li>'itervalues'
</li>
<li>'keys'
</li>
<li>'popitem'
</li>
<li>'values'
</li>
</ul>
<div class="section" id="section-attributes">
<h2><a class="toc-backref" href="#id62">7.1&nbsp;&nbsp;&nbsp;Section Attributes</a></h2>
<ul>
<li>main
<blockquote>
A reference to the main ConfigObj.
</blockquote>
</li>
<li>parent
<blockquote>
A reference to the 'parent' section, the section that this section is a
member of.
On the ConfigObj this attribute is a reference to itself. You can use this
to walk up the sections, stopping when <tt class="docutils literal">section.parent is section</tt>.
</blockquote>
</li>
<li>depth
<blockquote>
The nesting level of the current section.
If you create a new ConfigObj and add sections, 1 will be added to the
depth level between sections.
</blockquote>
</li>
<li>defaults
<blockquote>
This attribute is a list of scalars that came from default values. Values
that came from defaults aren't written out by the <tt class="docutils literal">write</tt> method.
Setting any of these values in the section removes them from the defaults
list.
</blockquote>
</li>
<li>default_values
<blockquote>
This attribute is a dictionary mapping keys to the default values for the
keys. By default it is an empty dictionary and is populated when you
validate the ConfigObj.
</blockquote>
</li>
<li>scalars, sections
<blockquote>
These attributes are normal lists, representing the order that members,
single values and subsections appear in the section. The order will either
be the order of the original config file, or the order that you added
members.
The order of members in this lists is the order that <tt class="docutils literal">write</tt> creates in
the config file. The <tt class="docutils literal">scalars</tt> list is output before the <tt class="docutils literal">sections</tt>
list.
Adding or removing members also alters these lists. You can manipulate the
lists directly to alter the order of members.
<div class="warning">
Warning
If you alter the <tt class="docutils literal">scalars</tt>, <tt class="docutils literal">sections</tt>, or <tt class="docutils literal">defaults</tt> attributes
so that they no longer reflect the contents of the section, you will
break your ConfigObj.
</div>
See also the <tt class="docutils literal">rename</tt> method.
</blockquote>
</li>
<li>comments
<blockquote>
This is a dictionary of comments associated with each member. Each entry is
a list of lines. These lines are written out before the member.
</blockquote>
</li>
<li>inline_comments
<blockquote>
This is another dictionary of comments associated with each member. Each
entry is a string that is put inline with the member.
</blockquote>
</li>
<li>configspec
<blockquote>
The configspec attribute is a dictionary mapping scalars to checks. A
check defines the expected type and possibly the allowed values for a
member.
The configspec has the same format as a config file, but instead of values
it has a specification for the value (which may include a default value).
The <a class="reference internal" href="#validate">validate</a> method uses it to check the config file makes sense. If a
configspec is passed in when the ConfigObj is created, then it is parsed
and broken up to become the <tt class="docutils literal">configspec</tt> attribute of each section.
If you didn't pass in a configspec, this attribute will be <tt class="docutils literal">None</tt> on the
root section (the main ConfigObj).
You can set the configspec attribute directly on a section.
See the <a class="reference internal" href="#validation">validation</a> section for full details of how to write configspecs.
</blockquote>
</li>
<li>extra_values
<blockquote>
By default an empty list. After <a class="reference internal" href="#validation">validation</a> this is populated with any members
of the section that don't appear in the configspec (i.e. they are additional
values). Rather than accessing this directly it may be more convenient to get
all the extra values in a config file using the <a class="reference internal" href="#get-extra-values">get_extra_values</a> function.
New in ConfigObj 4.7.0.
</blockquote>
</li>
</ul>
</div>
<div class="section" id="section-methods">
<h2><a class="toc-backref" href="#id63">7.2&nbsp;&nbsp;&nbsp;Section Methods</a></h2>
<ul>
<li>dict
<blockquote>
This method takes no arguments. It returns a deep copy of the section as a
dictionary. All subsections will also be dictionaries, and list values will
be copies, rather than references to the original <a class="footnote-reference" href="#id24" id="id10">[10]</a>.
</blockquote>
</li>
<li>rename
<blockquote>
<tt class="docutils literal">rename(oldkey, newkey)</tt>
This method renames a key, without affecting its position in the sequence.
</blockquote>
</li>
<li>merge
<blockquote>
<tt class="docutils literal">merge(indict)</tt>
This method is a recursive update method. It allows you to merge two
config files together.
You would typically use this to create a default ConfigObj and then merge
in user settings. This way users only need to specify values that are
different from the default.
For example :
<div class="highlight"><pre># def_cfg contains your default config settings
# user_cfg contains the user settings
cfg = ConfigObj(def_cfg)
usr = ConfigObj(user_cfg)
#
cfg.merge(usr)

&quot;&quot;&quot;
cfg now contains a combination of the default settings and the user
settings.

The user settings will have overwritten any of the default ones.
&quot;&quot;&quot;
</pre></div>
</blockquote>
</li>
<li>walk
<blockquote>
This method can be used to transform values and names. See <a class="reference internal" href="#walking-a-section">walking a
section</a> for examples and explanation.
</blockquote>
</li>
<li>as_bool
<blockquote>
<tt class="docutils literal">as_bool(key)</tt>
Returns <tt class="docutils literal">True</tt> if the key contains a string that represents <tt class="docutils literal">True</tt>, or
is the <tt class="docutils literal">True</tt> object.
Returns <tt class="docutils literal">False</tt> if the key contains a string that represents <tt class="docutils literal">False</tt>,
or is the <tt class="docutils literal">False</tt> object.
Raises a <tt class="docutils literal">ValueError</tt> if the key contains anything else.
Strings that represent <tt class="docutils literal">True</tt> are (not case sensitive):
<pre class="literal-block">
true, yes, on, 1
</pre>
Strings that represent <tt class="docutils literal">False</tt> are:
<pre class="literal-block">
false, no, off, 0
</pre>
</blockquote>
</li>
<li>as_int
<blockquote>
<tt class="docutils literal">as_int(key)</tt>
This returns the value contained in the specified key as an integer.
It raises a <tt class="docutils literal">ValueError</tt> if the conversion can't be done.
</blockquote>
</li>
<li>as_float
<blockquote>
<tt class="docutils literal">as_float(key)</tt>
This returns the value contained in the specified key as a float.
It raises a <tt class="docutils literal">ValueError</tt> if the conversion can't be done.
</blockquote>
</li>
<li>as_list
<blockquote>
<tt class="docutils literal">as_list(key)</tt>
This returns the value contained in the specified key as a list.
If it isn't a list it will be wrapped as a list so that you can
guarantee the returned value will be a list.
</blockquote>
</li>
<li>restore_default
<blockquote>
<tt class="docutils literal">restore_default(key)</tt>
Restore (and return) the default value for the specified key.
This method will only work for a ConfigObj that was created
with a configspec and has been validated.
If there is no default value for this key, <tt class="docutils literal">KeyError</tt> is raised.
</blockquote>
</li>
<li>restore_defaults
<blockquote>
<tt class="docutils literal">restore_defaults()</tt>
Recursively restore default values to all members
that have them.
This method will only work for a ConfigObj that was created
with a configspec and has been validated.
It doesn't delete or modify entries without default values.
</blockquote>
</li>
</ul>
</div>
<div class="section" id="walking-a-section">
<h2><a class="toc-backref" href="#id64">7.3&nbsp;&nbsp;&nbsp;Walking a Section</a></h2>
<div class="note">
Note
The walk method allows you to call a function on every member/name.
</div>
<div class="highlight"><pre>walk(function, raise_errors=True,
 call_on_sections=False, **keywargs)
</pre></div>
<tt class="docutils literal">walk</tt> is a method of the <tt class="docutils literal">Section</tt> object. This means it is also a method
of ConfigObj.
It walks through every member and calls a function on the keyword and value. It
walks recursively through subsections.
It returns a dictionary of all the computed values.
If the function raises an exception, the default is to propagate the error, and
stop. If <tt class="docutils literal">raise_errors=False</tt> then it sets the return value for that keyword
to <tt class="docutils literal">False</tt> instead, and continues. This is similar to the way <a class="reference internal" href="#validation">validation</a>
works.
Your function receives the arguments <tt class="docutils literal">(section, key)</tt>. The current value is
then <tt class="docutils literal">section[key]</tt> <a class="footnote-reference" href="#id25" id="id11">[11]</a>. Any unrecognised keyword arguments you pass to
walk, are passed on to the function.
Normally <tt class="docutils literal">walk</tt> just recurses into subsections. If you are transforming (or
checking) names as well as values, then you want to be able to change the names
of sections. In this case set <tt class="docutils literal">call_on_sections</tt> to <tt class="docutils literal">True</tt>. Now, on
encountering a sub-section, first the function is called for the whole
sub-section, and then it recurses into it's members. This means your function
must be able to handle receiving dictionaries as well as strings and lists.
If you are using the return value from <tt class="docutils literal">walk</tt> and <tt class="docutils literal">call_on_sections</tt>,
note that walk discards the return value when it calls your function.
<div class="caution">
Caution!
You can use <tt class="docutils literal">walk</tt> to transform the names of members of a section
but you mustn't add or delete members.
</div>
</div>
<div class="section" id="examples">
<h2><a class="toc-backref" href="#id65">7.4&nbsp;&nbsp;&nbsp;Examples</a></h2>
You can use this for transforming all values in your ConfigObj. For example
you might like the nested lists from ConfigObj 3. This was provided by the
<a class="reference external" href="http://www.voidspace.org.uk/python/modules.shtml#listquote">listquote</a> module. You could switch off the parsing for list values
(<tt class="docutils literal">list_values=False</tt>) and use listquote to parse every value.
Another thing you might want to do is use the Python escape codes in your
values. You might be used to using <tt class="docutils literal">\n</tt> for line feed and <tt class="docutils literal">\t</tt> for tab.
Obviously we'd need to decode strings that come from the config file (using the
escape codes). Before writing out we'll need to put the escape codes back in
encode.
As an example we'll write a function to use with walk, that encodes or decodes
values using the <tt class="docutils literal">string-escape</tt> codec.
The function has to take each value and set the new value. As a bonus we'll
create one function that will do decode or encode depending on a keyword
argument.
We don't want to work with section names, we're only transforming values, so
we can leave <tt class="docutils literal">call_on_sections</tt> as <tt class="docutils literal">False</tt>. This means the two datatypes we
have to handle are strings and lists, we can ignore everything else. (We'll
treat tuples as lists as well).
We're not using the return values, so it doesn't need to return anything, just
change the values if appropriate.
<div class="highlight"><pre>def string_escape(section, key, encode=False):
 &quot;&quot;&quot;
 A function to encode or decode using the &#39;string-escape&#39; codec.
 To be passed to the walk method of a ConfigObj.
 By default it decodes.
 To encode, pass in the keyword argument ``encode=True``.
 &quot;&quot;&quot;
 val = section[key]
 # is it a type we can work with
 # NOTE: for platforms where Python &gt; 2.2
 # you can use basestring instead of (str, unicode)
 if not isinstance(val, (str, unicode, list, tuple)):
 # no !
 return
 elif isinstance(val, (str, unicode)):
 # it&#39;s a string !
 if not encode:
 section[key] = val.decode(&#39;string-escape&#39;)
 else:
 section[key] = val.encode(&#39;string-escape&#39;)
 else:
 # it must be a list or tuple!
 # we&#39;ll be lazy and create a new list
 newval = []
 # we&#39;ll check every member of the list
 for entry in val:
 if isinstance(entry, (str, unicode)):
 if not encode:
 newval.append(entry.decode(&#39;string-escape&#39;))
 else:
 newval.append(entry.encode(&#39;string-escape&#39;))
 else:
 newval.append(entry)
 # done !
 section[key] = newval

# assume we have a ConfigObj called ``config``
#
# To decode
config.walk(string_escape)
#
# To encode.
# Because ``walk`` doesn&#39;t recognise the ``encode`` argument
# it passes it to our function.
config.walk(string_escape, encode=True)
</pre></div>
Here's a simple example of using <tt class="docutils literal">walk</tt> to transform names and values. One
usecase of this would be to create a standard config file with placeholders
for section and keynames. You can then use walk to create new config files
and change values and member names :
<div class="highlight"><pre># We use &#39;XXXX&#39; as a placeholder
config = &#39;&#39;&#39;
XXXXkey1 = XXXXvalue1
XXXXkey2 = XXXXvalue2
XXXXkey3 = XXXXvalue3
[XXXXsection1]
XXXXkey1 = XXXXvalue1
XXXXkey2 = XXXXvalue2
XXXXkey3 = XXXXvalue3
[XXXXsection2]
XXXXkey1 = XXXXvalue1
XXXXkey2 = XXXXvalue2
XXXXkey3 = XXXXvalue3
 [[XXXXsection1]]
 XXXXkey1 = XXXXvalue1
 XXXXkey2 = XXXXvalue2
 XXXXkey3 = XXXXvalue3
&#39;&#39;&#39;.splitlines()
cfg = ConfigObj(config)
#
def transform(section, key):
 val = section[key]
 newkey = key.replace(&#39;XXXX&#39;, &#39;CLIENT1&#39;)
 section.rename(key, newkey)
 if isinstance(val, (tuple, list, dict)):
 pass
 else:
 val = val.replace(&#39;XXXX&#39;, &#39;CLIENT1&#39;)
 section[newkey] = val
#
cfg.walk(transform, call_on_sections=True)
print cfg
ConfigObj({&#39;CLIENT1key1&#39;: &#39;CLIENT1value1&#39;, &#39;CLIENT1key2&#39;: &#39;CLIENT1value2&#39;,
&#39;CLIENT1key3&#39;: &#39;CLIENT1value3&#39;,
&#39;CLIENT1section1&#39;: {&#39;CLIENT1key1&#39;: &#39;CLIENT1value1&#39;,
 &#39;CLIENT1key2&#39;: &#39;CLIENT1value2&#39;, &#39;CLIENT1key3&#39;: &#39;CLIENT1value3&#39;},
&#39;CLIENT1section2&#39;: {&#39;CLIENT1key1&#39;: &#39;CLIENT1value1&#39;,
 &#39;CLIENT1key2&#39;: &#39;CLIENT1value2&#39;, &#39;CLIENT1key3&#39;: &#39;CLIENT1value3&#39;,
 &#39;CLIENT1section1&#39;: {&#39;CLIENT1key1&#39;: &#39;CLIENT1value1&#39;,
 &#39;CLIENT1key2&#39;: &#39;CLIENT1value2&#39;, &#39;CLIENT1key3&#39;: &#39;CLIENT1value3&#39;}}})
</pre></div>
</div>
</div>
<div class="section" id="exceptions">
<h1><a class="toc-backref" href="#id66">8&nbsp;&nbsp;&nbsp;Exceptions</a></h1>
There are several places where ConfigObj may raise exceptions (other than
because of bugs).
<ol class="arabic">
<li><dl class="first docutils">
<dt>If a configspec filename you pass in doesn't exist, or a config file</dt>
<dd>filename doesn't exist and <tt class="docutils literal">file_error=True</tt>, an <tt class="docutils literal">IOError</tt> will be
raised.
</dd>
</dl>
</li>
<li><dl class="first docutils">
<dt>If you try to set a non-string key, or a non string value when</dt>
<dd><tt class="docutils literal">stringify=False</tt>, a <tt class="docutils literal">TypeError</tt> will be raised.
</dd>
</dl>
</li>
<li>A badly built config file will cause parsing errors.
</li>
<li>A parsing error can also occur when reading a configspec.
</li>
<li><dl class="first docutils">
<dt>In string interpolation you can specify a value that doesn't exist, or</dt>
<dd>create circular references (recursion).
</dd>
</dl>
</li>
</ol>
Number 5 (which is actually two different types of exceptions) is documented
in <a class="reference internal" href="#string-interpolation">String Interpolation</a>.
This section is about errors raised during parsing.
The base error class is <tt class="docutils literal">ConfigObjError</tt>. This is a subclass of
<tt class="docutils literal">SyntaxError</tt>, so you can trap for <tt class="docutils literal">SyntaxError</tt> without needing to
directly import any of the ConfigObj exceptions.
The following other exceptions are defined (all deriving from
<tt class="docutils literal">ConfigObjError</tt>) :
<ul>
<li><tt class="docutils literal">NestingError</tt>
<blockquote>
This error indicates either a mismatch in the brackets in a section marker,
or an excessive level of nesting.
</blockquote>
</li>
<li><tt class="docutils literal">ParseError</tt>
<blockquote>
This error indicates that a line is badly written. It is neither a valid
<tt class="docutils literal">key = value</tt> line, nor a valid section marker line, nor a comment line.
</blockquote>
</li>
<li><tt class="docutils literal">DuplicateError</tt>
<blockquote>
The keyword or section specified already exists.
</blockquote>
</li>
<li><tt class="docutils literal">ConfigspecError</tt>
<blockquote>
An error occurred whilst parsing a configspec.
</blockquote>
</li>
<li><tt class="docutils literal">UnreprError</tt>
<blockquote>
An error occurred when parsing a value in <a class="reference internal" href="#unrepr-mode">unrepr mode</a>.
</blockquote>
</li>
<li><tt class="docutils literal">ReloadError</tt>
<blockquote>
<tt class="docutils literal">reload</tt> was called on a ConfigObj instance that doesn't have a valid
filename attribute.
</blockquote>
</li>
</ul>
When parsing a configspec, ConfigObj will stop on the first error it
encounters. It will raise a <tt class="docutils literal">ConfigspecError</tt>. This will have an <tt class="docutils literal">error</tt>
attribute, which is the actual error that was raised.
Behaviour when parsing a config file depends on the option <tt class="docutils literal">raise_errors</tt>.
If ConfigObj encounters an error while parsing a config file:
<blockquote>
If <tt class="docutils literal">raise_errors=True</tt> then ConfigObj will raise the appropriate error
and parsing will stop.
If <tt class="docutils literal">raise_errors=False</tt> (the default) then parsing will continue to the
end and all errors will be collected.
</blockquote>
If <tt class="docutils literal">raise_errors</tt> is False and multiple errors are found a <tt class="docutils literal">ConfigObjError</tt>
is raised. The error raised has a <tt class="docutils literal">config</tt> attribute, which is the parts of
the ConfigObj that parsed successfully. It also has an attribute <tt class="docutils literal">errors</tt>,
which is a list of all the errors raised. Each entry in the list is an
instance of the appropriate error type. Each one has the following attributes
(useful for delivering a sensible error message to your user) :
<ul class="simple">
<li><tt class="docutils literal">line</tt>: the original line that caused the error.</li>
<li><tt class="docutils literal">line_number</tt>: its number in the config file.</li>
<li><tt class="docutils literal">message</tt>: the error message that accompanied the error.</li>
</ul>
If only one error is found, then that error is re-raised. The error still has
the <tt class="docutils literal">config</tt> and <tt class="docutils literal">errors</tt> attributes. This means that your error handling
code can be the same whether one error is raised in parsing , or several.
It also means that in the most common case (a single error) a useful error
message will be raised.
<div class="note">
Note
One wrongly written line could break the basic structure of your config
file. This could cause every line after it to flag an error, so having a
list of all the lines that caused errors may not be as useful as it sounds.
</div>
</div>
<div class="section" id="validation">
<h1><a class="toc-backref" href="#id67">9&nbsp;&nbsp;&nbsp;Validation</a></h1>
<div class="hint">
Hint
The system of configspecs can seem confusing at first, but is actually
quite simple and powerful. The best reference is my article on ConfigObj:
<ul class="last simple">
<li><a class="reference external" href="http://www.voidspace.org.uk/python/articles/configobj.shtml">An Introduction to ConfigObj</a></li>
</ul>
</div>
Validation is done through a combination of the <a class="reference internal" href="#configspec">configspec</a> and a <tt class="docutils literal">Validator</tt>
object. For this you need validate.py <a class="footnote-reference" href="#id26" id="id12">[12]</a>. See <a class="reference internal" href="#downloading">downloading</a> if you don't
have a copy.
Validation can perform two different operations :
<ol class="arabic">
<li><dl class="first docutils">
<dt>Check that a value meets a specification. For example, check that a value</dt>
<dd>is an integer between one and six, or is a choice from a specific set of
options.
</dd>
</dl>
</li>
<li><dl class="first docutils">
<dt>It can convert the value into the type required. For example, if one of</dt>
<dd>your values is a port number, validation will turn it into an integer for
you.
</dd>
</dl>
</li>
</ol>
So validation can act as a transparent layer between the datatypes of your
application configuration (boolean, integers, floats, etc) and the text format
of your config file.
<div class="section" id="configspec">
<h2><a class="toc-backref" href="#id68">9.1&nbsp;&nbsp;&nbsp;configspec</a></h2>
The <tt class="docutils literal">validate</tt> method checks members against an entry in the configspec. Your
configspec therefore resembles your config file, with a check for every member.
In order to perform validation you need a <tt class="docutils literal">Validator</tt> object. This has
several useful built-in check functions. You can also create your own custom
functions and register them with your Validator object.
Each check is the name of one of these functions, including any parameters and
keyword arguments. The configspecs look like function calls, and they map to
function calls.
The basic datatypes that an un-extended Validator can test for are :
<ul class="simple">
<li>boolean values (True and False)</li>
<li>integers (including minimum and maximum values)</li>
<li>floats (including min and max)</li>
<li>strings (including min and max length)</li>
<li>IP addresses (v4 only)</li>
</ul>
It can also handle lists of these types and restrict a value to being one from
a set of options.
An example configspec is going to look something like:
<pre class="literal-block">
port = integer(0, 100)
user = string(max=25)
mode = option('quiet', 'loud', 'silent')
</pre>
You can specify default values, and also have the same configspec applied to
several sections. This is called <a class="reference internal" href="#repeated-sections">repeated sections</a>.
For full details on writing configspecs, please refer to the <a class="reference external" href="http://www.voidspace.org.uk/python/validate.html">validate.py
documentation</a>.
<div class="important">
Important
Your configspec is read by ConfigObj in the same way as a config file.
That means you can do interpolation within your configspec.
In order to allow this, checks in the 'DEFAULT' section (of the root level
of your configspec) are not used.
If you want to use a configspec without interpolation being done in it
you can create your configspec manually and switch off interpolation:
<div class="last"><div class="highlight"><pre>from configobj import ConfigObj

configspec = ConfigObj(spec_filename, interpolation=False, list_values=False,
 _inspec=True)
conf = ConfigObj(config_filename, configspec=configspec)
</pre></div>
</div></div>
If you need to specify the encoding of your configspec, then you can pass in a
ConfigObj instance as your configspec. When you read your configspec file, you
must specify <tt class="docutils literal">list_values=False</tt>. If you need to support hashes in
configspec values then you must also pass in <tt class="docutils literal">_inspec=True</tt>.
<div class="highlight"><pre>from configobj import ConfigObj
configspec = ConfigObj(configspecfilename, encoding=&#39;UTF8&#39;,
 list_values=False, _inspec=True)
config = ConfigObj(filename, configspec=configspec)
</pre></div>
</div>
<div class="section" id="type-conversion">
<h2><a class="toc-backref" href="#id69">9.2&nbsp;&nbsp;&nbsp;Type Conversion</a></h2>
By default, validation does type conversion. This means that if you specify
<tt class="docutils literal">integer</tt> as the check, then calling <a class="reference internal" href="#validate">validate</a> will actually change the value
to an integer (so long as the check succeeds).
It also means that when you call the <a class="reference internal" href="#write">write</a> method, the value will be converted
back into a string using the <tt class="docutils literal">str</tt> function.
To switch this off, and leave values as strings after validation, you need to
set the <a class="reference internal" href="#stringify">stringify</a> attribute to <tt class="docutils literal">False</tt>. If this is the case, attempting to
set a value to a non-string will raise an error.
</div>
<div class="section" id="default-values">
<h2><a class="toc-backref" href="#id70">9.3&nbsp;&nbsp;&nbsp;Default Values</a></h2>
You can set a default value in your check. If the value is missing from the
config file then this value will be used instead. This means that your user
only has to supply values that differ from the defaults.
If you don't supply a default then for a value to be missing is an error,
and this will show in the <a class="reference internal" href="#return-value">return value</a> from validate.
Additionally you can set the default to be <tt class="docutils literal">None</tt>. This means the value will
be set to <tt class="docutils literal">None</tt> (the object) whichever check is used. (It will be set to
<tt class="docutils literal">''</tt> rather than <tt class="docutils literal">None</tt> if <a class="reference internal" href="#stringify">stringify</a> is <tt class="docutils literal">False</tt>). You can use this
to easily implement optional values in your config files.
<pre class="literal-block">
port = integer(0, 100, default=80)
user = string(max=25, default=0)
mode = option('quiet', 'loud', 'silent', default='loud')
nick = string(default=None)
</pre>
<div class="note">
Note
Because the default goes through type conversion, it also has to pass the
check.
Note that <tt class="docutils literal">default=None</tt> is case sensitive.
</div>
<div class="section" id="id13">
<h3><a class="toc-backref" href="#id71">9.3.1&nbsp;&nbsp;&nbsp;List Values</a></h3>
It's possible that you will want to specify a list as a default value. To avoid
confusing syntax with commas and quotes you use a list constructor to specify
that keyword arguments are lists. This includes the <tt class="docutils literal">default</tt> value. This
makes checks look something like:
<pre class="literal-block">
checkname(default=list('val1', 'val2', 'val3'))
</pre>
This works with all keyword arguments, but is most useful for default values.
</div>
</div>
<div class="section" id="repeated-sections">
<h2><a class="toc-backref" href="#id72">9.4&nbsp;&nbsp;&nbsp;Repeated Sections</a></h2>
Repeated sections are a way of specifying a configspec for a section that
should be applied to all unspecified subsections in the same section.
The easiest way of explaining this is to give an example. Suppose you have a
config file that describes a dog. That dog has various attributes, but it can
also have many fleas. You don't know in advance how many fleas there will be,
or what they will be called, but you want each flea validated against the same
configspec.
We can define a section called fleas. We want every flea in that section
(every sub-section) to have the same configspec applied to it. We do this by
defining a single section called <tt class="docutils literal">__many__</tt>.
<pre class="literal-block">
[dog]
name = string(default=Rover)
age = float(0, 99, default=0)

[[fleas]]

[[[__many__]]]
 bloodsucker = boolean(default=True)
 children = integer(default=10000)
 size = option(small, tiny, micro, default=tiny)
</pre>
Every flea on our dog will now be validated using the <tt class="docutils literal">__many__</tt> configspec.
<tt class="docutils literal">__many__</tt> sections can have sub-sections, including their own <tt class="docutils literal">__many__</tt>
sub-sections. Defaults work in the normal way in repeated sections.
</div>
<div class="section" id="repeated-values">
<h2><a class="toc-backref" href="#id73">9.5&nbsp;&nbsp;&nbsp;Repeated Values</a></h2>
As well as using <tt class="docutils literal">__many__</tt> to validate unspecified sections you can use it to validate values. For
example, to specify that all values in a section should be integers:
<pre class="literal-block">
[section]
 __many__ = integer
</pre>
If you want to use repeated values alongside repeated sections you can call one <tt class="docutils literal">__many__</tt> and the
other <tt class="docutils literal">___many___</tt> (with three underscores).
</div>
<div class="section" id="copy-mode">
<h2><a class="toc-backref" href="#id74">9.6&nbsp;&nbsp;&nbsp;Copy Mode</a></h2>
Because you can specify default values in your configspec, you can use
ConfigObj to write out default config files for your application.
However, normally values supplied from a default in a configspec are not
written out by the <tt class="docutils literal">write</tt> method.
To do this, you need to specify <tt class="docutils literal">copy=True</tt> when you call validate. As well
as not marking values as default, all the comments in the configspec file
will be copied into your ConfigObj instance.
<div class="highlight"><pre>from configobj import ConfigObj
from validate import Validator
vdt = Validator()
config = ConfigObj(configspec=&#39;default.ini&#39;)
config.filename = &#39;new_default.ini&#39;
config.validate(vdt, copy=True)
config.write()
</pre></div>
If you need to support hashes in the configspec values then you must create
it with <tt class="docutils literal">_inspec=True</tt>. This has the side effect of switching off the parsing
of inline comments, meaning that they won't be copied into the new config file.
(ConfigObj syntax is slightly different from configspec syntax and the parser
can't support both inline comments and hashes in configspec values.)
</div>
<div class="section" id="validation-and-interpolation">
<h2><a class="toc-backref" href="#id75">9.7&nbsp;&nbsp;&nbsp;Validation and Interpolation</a></h2>
String interpolation and validation don't play well together. When validation
changes type it sets the value. If the value uses interpolation, then the
interpolation reference would normally be overwritten. Calling <tt class="docutils literal">write</tt> would
then use the absolute value and the interpolation reference would be lost.
As a compromise - if the value is unchanged by validation then it is not reset.
This means strings that pass through validation unmodified will not be
overwritten. If validation changes type - the value has to be overwritten, and
any interpolation references are lost.
</div>
<div class="section" id="extra-values">
<h2><a class="toc-backref" href="#id76">9.8&nbsp;&nbsp;&nbsp;Extra Values</a></h2>
After validation the <tt class="docutils literal">extra_values</tt> member of every section that is listed in
the configspec will be populated with the names of members that are in the
config file but not in the configspec.
If you are reporting configuration errors to your user this information can be
useful, for example some missing entries may be due to misspelt entries that
appear as extra values.
See the <a class="reference internal" href="#get-extra-values">get_extra_values</a> function
New in ConfigObj 4.7.0.
</div>
<div class="section" id="simpleval">
<h2><a class="toc-backref" href="#id77">9.9&nbsp;&nbsp;&nbsp;SimpleVal</a></h2>
You may not need a full validation process, but still want to check if all the
expected values are present.
Provided as part of the ConfigObj module is the <tt class="docutils literal">SimpleVal</tt> object. This has
a dummy <tt class="docutils literal">test</tt> method that always passes.
The only reason a test will fail is if the value is missing. The return value
from <tt class="docutils literal">validate</tt> will either be <tt class="docutils literal">True</tt>, meaning all present, or a dictionary
with <tt class="docutils literal">False</tt> for all missing values/sections.
To use it, you still need to pass in a valid configspec when you create the
ConfigObj, but just set all the values to <tt class="docutils literal">''</tt>. Then create an instance of
<tt class="docutils literal">SimpleVal</tt> and pass it to the <tt class="docutils literal">validate</tt> method.
As a trivial example if you had the following config file:
<pre class="literal-block">
# config file for an application
port = 80
protocol = http
domain = voidspace
top_level_domain = org.uk
</pre>
You would write the following configspec:
<pre class="literal-block">
port = ''
protocol = ''
domain = ''
top_level_domain = ''
</pre>
<div class="highlight"><pre>config = Configobj(filename, configspec=configspec)
val = SimpleVal()
test = config.validate(val)
if test == True:
 print &#39;All values present.&#39;
elif test == False:
 print &#39;No values present!&#39;
else:
 for entry in test:
 if test[entry] == False:
 print &#39;&quot;%s&quot; missing.&#39; % entry
</pre></div>
</div>
</div>
<div class="section" id="empty-values">
<h1><a class="toc-backref" href="#id78">10&nbsp;&nbsp;&nbsp;Empty values</a></h1>
Many config files from other applications allow empty values. As of version
4.3.0, ConfigObj will read these as an empty string.
A new option/attribute has been added (<tt class="docutils literal">write_empty_values</tt>) to allow
ConfigObj to write empty strings as empty values.
<div class="highlight"><pre>from configobj import ConfigObj
cfg = &#39;&#39;&#39;
 key =
 key2 = # a comment
&#39;&#39;&#39;.splitlines()
config = ConfigObj(cfg)
print config
ConfigObj({&#39;key&#39;: &#39;&#39;, &#39;key2&#39;: &#39;&#39;})

config.write_empty_values = True
for line in config.write():
 print line

key =
key2 = # a comment
</pre></div>
</div>
<div class="section" id="unrepr-mode">
<h1><a class="toc-backref" href="#id79">11&nbsp;&nbsp;&nbsp;unrepr mode</a></h1>
The <tt class="docutils literal">unrepr</tt> option allows you to store and retrieve the basic Python
data-types using config files. It has to use a slightly different syntax to
normal ConfigObj files. Unsurprisingly it uses Python syntax.
This means that lists are different (they are surrounded by square brackets),
and strings must be quoted.
The types that <tt class="docutils literal">unrepr</tt> can work with are :
<blockquote>
<div class="line-block">
<div class="line">strings, lists tuples</div>
<div class="line">None, True, False</div>
<div class="line">dictionaries, integers, floats</div>
<div class="line">longs and complex numbers</div>
</div>
</blockquote>
You can't store classes, types or instances.
<tt class="docutils literal">unrepr</tt> uses <tt class="docutils literal">repr(object)</tt> to write out values, so it currently doesn't
check that you are writing valid objects. If you attempt to read an unsupported
value, ConfigObj will raise a <tt class="docutils literal">configobj.UnknownType</tt> exception.
Values that are triple quoted cased. The triple quotes are removed before
converting. This means that you can use triple quotes to write dictionaries
over several lines in your config files. They won't be written like this
though.
If you are writing config files by hand, for use with <tt class="docutils literal">unrepr</tt>, you should
be aware of the following differences from normal ConfigObj syntax :
<blockquote>
<div class="line-block">
<div class="line">List : <tt class="docutils literal">['A List', 'With', 'Strings']</tt></div>
<div class="line">Strings : <tt class="docutils literal">&quot;Must be quoted.&quot;</tt></div>
<div class="line">Backslash : <tt class="docutils literal">&quot;The backslash must be escaped \\&quot;</tt></div>
</div>
</blockquote>
These all follow normal Python syntax.
In unrepr mode inline comments are not saved. This is because lines are
parsed using the <a class="reference external" href="http://docs.python.org/lib/compiler.html">compiler package</a>
which discards comments.
</div>
<div class="section" id="string-interpolation">
<h1><a class="toc-backref" href="#id80">12&nbsp;&nbsp;&nbsp;String Interpolation</a></h1>
<div class="note">
Note
String interpolation can slow down (slightly) the fetching of values
from your config object. If you aren't using interpolation and it
is performance critical then create your instance with
<tt class="docutils literal">interpolation=False</tt>.
</div>
ConfigObj allows string interpolation similar to the way <tt class="docutils literal">ConfigParser</tt>
or <tt class="docutils literal">string.Template</tt> work. The value of the <tt class="docutils literal">interpolation</tt> attribute
determines which style of interpolation you want to use. Valid values are
&quot;ConfigParser&quot; or &quot;Template&quot; (case-insensitive, so &quot;configparser&quot; and
&quot;template&quot; will also work). For backwards compatibility reasons, the value
<tt class="docutils literal">True</tt> is also a valid value for the <tt class="docutils literal">interpolation</tt> attribute, and
will select <tt class="docutils literal">ConfigParser</tt>-style interpolation. At some undetermined point
in the future, that default may change to <tt class="docutils literal">Template</tt>-style interpolation.
For <tt class="docutils literal">ConfigParser</tt>-style interpolation, you specify a value to be
substituted by including <tt class="docutils literal">%(name)s</tt> in the value.
For <tt class="docutils literal">Template</tt>-style interpolation, you specify a value to be substituted
by including <tt class="docutils literal">${cl}name{cr}</tt> in the value. Alternately, if 'name' is a valid
Python identifier (i.e., is composed of nothing but alphanumeric characters,
plus the underscore character), then the braces are optional and the value
can be written as <tt class="docutils literal">$name</tt>.
Note that <tt class="docutils literal">ConfigParser</tt>-style interpolation and <tt class="docutils literal">Template</tt>-style
interpolation are mutually exclusive; you cannot have a configuration file
that's a mix of one or the other. Pick one and stick to it. <tt class="docutils literal">Template</tt>-style
interpolation is simpler to read and write by hand, and is recommended if
you don't have a particular reason to use <tt class="docutils literal">ConfigParser</tt>-style.
Interpolation checks first the current section to see if <tt class="docutils literal">name</tt> is the key
to a value. ('name' is case sensitive).
If it doesn't find it, next it checks the 'DEFAULT' sub-section of the current
section.
If it still doesn't find it, it moves on to check the parent section and the
parent section's 'DEFAULT' subsection, and so on all the way up to the main
section.
If the value specified isn't found in any of these locations, then a
<tt class="docutils literal">MissingInterpolationOption</tt> error is raised (a subclass of
<tt class="docutils literal">ConfigObjError</tt>).
If it is found then the returned value is also checked for substitutions. This
allows you to make up compound values (for example directory paths) that use
more than one default value. It also means it's possible to create circular
references. If there are any circular references which would cause an infinite
interpolation loop, an <tt class="docutils literal">InterpolationLoopError</tt> is raised.
Both of these errors are subclasses of <tt class="docutils literal">InterpolationError</tt>, which is a
subclass of <tt class="docutils literal">ConfigObjError</tt>.
String interpolation and validation don't play well together. This is because
validation overwrites values - and so may erase the interpolation references.
See <a class="reference internal" href="#validation-and-interpolation">Validation and Interpolation</a>. (This can only happen if validation
has to change the value).
New in ConfigObj 4.7.0: String interpolation is now done in members of list
values.
<div class="section" id="string-interpolation-and-list-values">
<h2><a class="toc-backref" href="#id81">12.1&nbsp;&nbsp;&nbsp;String Interpolation and List Values</a></h2>
Since version 4.7 string interpolation is done on string members of list values.
If interpolation changes any members of the list then what you get back is a
copy of the list rather than the original list.
This makes fetching list values slightly slower when interpolation is on, it
also means that if you mutate the list changes won't be reflected in the
original list:
<div class="highlight"><pre>&gt;&gt;&gt; c = ConfigObj()
&gt;&gt;&gt; c[&#39;foo&#39;] = &#39;boo&#39;
&gt;&gt;&gt; c[&#39;bar&#39;] = [&#39;%(foo)s&#39;]
&gt;&gt;&gt; c[&#39;bar&#39;]
[&#39;boo&#39;]
&gt;&gt;&gt; c[&#39;bar&#39;].append(&#39;fish&#39;)
&gt;&gt;&gt; c[&#39;bar&#39;]
[&#39;boo&#39;]
</pre></div>
Instead of mutating the list you must create a new list and reassign it.
</div>
</div>
<div class="section" id="comments">
<h1><a class="toc-backref" href="#id82">13&nbsp;&nbsp;&nbsp;Comments</a></h1>
Any line that starts with a '#', possibly preceded by whitespace, is a comment.
If a config file starts with comments then these are preserved as the
<a class="reference internal" href="#initial-comment">initial_comment</a>.
If a config file ends with comments then these are preserved as the
<a class="reference internal" href="#final-comment">final_comment</a>.
Every key or section marker may have lines of comments immediately above it.
These are saved as the <tt class="docutils literal">comments</tt> attribute of the section. Each member is a
list of lines.
You can also have a comment inline with a value. These are saved as the
<tt class="docutils literal">inline_comments</tt> attribute of the section, with one entry per member of the
section.
Subsections (section markers in the config file) can also have comments.
See <a class="reference internal" href="#section-attributes">Section Attributes</a> for more on these attributes.
These comments are all written back out by the <tt class="docutils literal">write</tt> method.
</div>
<div class="section" id="flatten-errors">
<h1><a class="toc-backref" href="#id83">14&nbsp;&nbsp;&nbsp;flatten_errors</a></h1>
<div class="highlight"><pre>flatten_errors(cfg, res)
</pre></div>
<a class="reference internal" href="#validation">Validation</a> is a powerful way of checking that the values supplied by the user
make sense.
The <a class="reference internal" href="#validate">validate</a> method returns a results dictionary that represents pass or fail
for each value. This doesn't give you any information about why the check
failed.
<tt class="docutils literal">flatten_errors</tt> is an example function that turns a results dictionary into
a flat list, that only contains values that failed.
<tt class="docutils literal">cfg</tt> is the ConfigObj instance being checked, <tt class="docutils literal">res</tt> is the results
dictionary returned by <tt class="docutils literal">validate</tt>.
It returns a list of keys that failed. Each member of the list is a tuple:
<pre class="literal-block">
([list of sections...], key, result)
</pre>
If <tt class="docutils literal">validate</tt> was called with <tt class="docutils literal">preserve_errors=False</tt> (the default)
then <tt class="docutils literal">result</tt> will always be <tt class="docutils literal">False</tt>.
list of sections is a flattened list of sections that the key was found
in.
If the section was missing then key will be <tt class="docutils literal">None</tt>.
If the value (or section) was missing then <tt class="docutils literal">result</tt> will be <tt class="docutils literal">False</tt>.
If <tt class="docutils literal">validate</tt> was called with <tt class="docutils literal">preserve_errors=True</tt> and a value
was present, but failed the check, then <tt class="docutils literal">result</tt> will be the exception
object returned. You can use this as a string that describes the failure.
For example :
<blockquote>
The value &quot;3&quot; is of the wrong type.</blockquote>
<div class="section" id="example-usage">
<h2><a class="toc-backref" href="#id84">14.1&nbsp;&nbsp;&nbsp;Example Usage</a></h2>
The output from <tt class="docutils literal">flatten_errors</tt> is a list of tuples.
Here is an example of how you could present this information to the user.
<div class="highlight"><pre>vtor = validate.Validator()
# ini is your config file - cs is the configspec
cfg = ConfigObj(ini, configspec=cs)
res = cfg.validate(vtor, preserve_errors=True)
for entry in flatten_errors(cfg, res):
 # each entry is a tuple
 section_list, key, error = entry
 if key is not None:
 section_list.append(key)
 else:
 section_list.append(&#39;[missing section]&#39;)
 section_string = &#39;, &#39;.join(section_list)
 if error == False:
 error = &#39;Missing value or section.&#39;
 print section_string, &#39; = &#39;, error
</pre></div>
</div>
</div>
<div class="section" id="get-extra-values">
<h1><a class="toc-backref" href="#id85">15&nbsp;&nbsp;&nbsp;get_extra_values</a></h1>
<div class="highlight"><pre>get_extra_values(conf)
</pre></div>
New in ConfigObj 4.7.0.
Find all the values and sections not in the configspec from a validated
ConfigObj.
<tt class="docutils literal">get_extra_values</tt> returns a list of tuples where each tuple represents
either an extra section, or an extra value.
The tuples contain two values, a tuple representing the section the value
is in and the name of the extra values. For extra values in the top level
section the first member will be an empty tuple. For values in the 'foo'
section the first member will be <tt class="docutils literal">('foo',)</tt>. For members in the 'bar'
subsection of the 'foo' section the first member will be <tt class="docutils literal">('foo', 'bar')</tt>.
Extra sections will only have one entry. Values and subsections inside
an extra section aren't listed separately.
NOTE: If you call <tt class="docutils literal">get_extra_values</tt> on a ConfigObj instance that hasn't
been validated it will return an empty list.
<div class="section" id="id14">
<h2><a class="toc-backref" href="#id86">15.1&nbsp;&nbsp;&nbsp;Example Usage</a></h2>
The output from <tt class="docutils literal">get_extra_values</tt> is a list of tuples.
Here is an example of how you could present this information to the user.
<div class="highlight"><pre>vtor = validate.Validator()
# ini is your config file - cs is the configspec
cfg = ConfigObj(ini, configspec=cs)
cfg.validate(vtor, preserve_errors=True)

for sections, name in get_extra_values(cfg):

# this code gets the extra values themselves
 the_section = cfg
 for section in sections:
 the_section = cfg[section]

# the_value may be a section or a value
 the_value = the_section[name]

section_or_value = &#39;value
 if isinstance(the_value, dict):
 # Sections are subclasses of dict
 section_or_value = &#39;section&#39;

section_string = &#39;, &#39;.join(sections) or &quot;top level&quot;
 print &#39;Extra entry in section: %s. Entry %r is a %s&#39; % (section_string, name, section_or_value)
</pre></div>
</div>
</div>
<div class="section" id="credits">
<h1><a class="toc-backref" href="#id87">16&nbsp;&nbsp;&nbsp;CREDITS</a></h1>
ConfigObj 4 is written by (and copyright) <a class="reference external" href="http://www.voidspace.org.uk/python/weblog/index.shtml">Michael Foord</a> and
<a class="reference external" href="http://www.teknico.net">Nicola Larosa</a>.
Particularly thanks to Nicola Larosa for help on the config file spec, the
validation system and the doctests.
validate.py was originally written by Michael Foord and Mark Andrews.
Thanks to many others for input, patches and bugfixes.
</div>
<div class="section" id="license">
<h1><a class="toc-backref" href="#id88">17&nbsp;&nbsp;&nbsp;LICENSE</a></h1>
ConfigObj, and related files, are licensed under the BSD license. This is a
very unrestrictive license, but it comes with the usual disclaimer. This is
free software: test it, break it, just don't blame us if it eats your data !
Of course if it does, let us know and we'll fix the problem so it doesn't
happen to anyone else:
<pre class="literal-block">
Copyright (c) 2004 - 2010, Michael Foord &amp; Nicola Larosa
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

* Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

* Redistributions in binary form must reproduce the above
      copyright notice, this list of conditions and the following
      disclaimer in the documentation and/or other materials provided
      with the distribution.

* Neither the name of Michael Foord nor Nicola Larosa
      may be used to endorse or promote products derived from this
      software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
&quot;AS IS&quot; AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
</pre>
You should also be able to find a copy of this license at : <a class="reference external" href="http://www.voidspace.org.uk/python/license.shtml">BSD License</a>
</div>
<div class="section" id="todo">
<h1><a class="toc-backref" href="#id89">18&nbsp;&nbsp;&nbsp;TODO</a></h1>
Better support for configuration from multiple files, including tracking
where the original file came from and writing changes to the correct
file.
Make <tt class="docutils literal">newline</tt> a keyword argument (as well as an attribute) ?
<tt class="docutils literal">UTF16</tt> encoded files, when returned as a list of lines, will have the
BOM at the start of every line. Should this be removed from all but the
first line ?
Option to set warning type for unicode decode ? (Defaults to strict).
A method to optionally remove uniform indentation from multiline values.
(do as an example of using <tt class="docutils literal">walk</tt> - along with string-escape)
Should the results dictionary from validate be an ordered dictionary if
<a class="reference external" href="http://www.voidspace.org.uk/python/odict.html">odict</a> is available ?
Implement some of the sequence methods (which include slicing) from the
newer <tt class="docutils literal">odict</tt> ?
Preserve line numbers of values (and possibly the original text of each value).
</div>
<div class="section" id="issues">
<h1><a class="toc-backref" href="#id90">19&nbsp;&nbsp;&nbsp;ISSUES</a></h1>
<div class="note">
Note
Please file any bug reports to <a class="reference external" href="http://www.voidspace.org.uk/python/weblog/index.shtml">Michael Foord</a> or the ConfigObj
<a class="reference external" href="http://lists.sourceforge.net/lists/listinfo/configobj-develop">Mailing List</a>.
</div>
There is currently no way to specify the encoding of a configspec file.
As a consequence of the changes to configspec handling in version 4.6.0, when
you create a ConfigObj instance and provide a configspec, the configspec
attribute is only set on the ConfigObj instance - it isn't set on the sections until you validate. You also can't set the configspec attribute to be a dictionary. This wasn't documented but did work previously.
In order to fix the problem with hashes in configspecs I had to turn off the parsing of inline comments in configspecs. This will only affect you if you are using <tt class="docutils literal">copy=True</tt> when validating and expecting inline comments to be copied from the configspec into the ConfigObj instance (all other comments will be copied as usual).
If you create the configspec by passing in a ConfigObj instance (usual way is to pass in a filename or list of lines) then you should pass in <tt class="docutils literal">_inspec=True</tt> to the constructor to allow hashes in values. This is the magic that switches off inline comment parsing.
When using <tt class="docutils literal">copy</tt> mode for validation, it won't copy <tt class="docutils literal">DEFAULT</tt>
sections. This is so that you can use interpolation in configspec
files. This is probably true even if interpolation is off in the
configspec.
You can't have a keyword with the same name as a section (in the same
section). They are both dictionary keys - so they would overlap.
ConfigObj doesn't quote and unquote values if <tt class="docutils literal">list_values=False</tt>.
This means that leading or trailing whitespace in values will be lost when
writing. (Unless you manually quote).
Interpolation checks first the current section, then the 'DEFAULT' subsection
of the current section, before moving on to the current section's parent and
so on up the tree.
Does it matter that we don't support the ':' divider, which is supported
by <tt class="docutils literal">ConfigParser</tt> ?
String interpolation and validation don't play well together. When
validation changes type it sets the value. This will correctly fetch the
value using interpolation - but then overwrite the interpolation reference.
If the value is unchanged by validation (it's a string) - but other types
will be.
</div>
<div class="section" id="changelog">
<h1><a class="toc-backref" href="#id91">20&nbsp;&nbsp;&nbsp;CHANGELOG</a></h1>
This is an abbreviated changelog showing the major releases up to version 4.
From version 4 it lists all releases and changes.
<div class="section" id="version-4-7-2">
<h2><a class="toc-backref" href="#id92">20.1&nbsp;&nbsp;&nbsp;2010/02/27 - Version 4.7.2</a></h2>
<ul class="simple">
<li>BUGFIX: Restore Python 2.3 compatibility</li>
<li>BUGFIX: Members that were lists were being returned as copies due to interpolation
introduced in 4.7. Lists are now only copies if interpolation changes a list
member.</li>
<li>BUGFIX: <tt class="docutils literal">pop</tt> now does interpolation in list values as well.</li>
<li>BUGFIX: where interpolation matches a section name rather than a value it is
ignored instead of raising an exception on fetching the item.</li>
<li>BUGFIX: values that use interpolation to reference members that don't exist can
now be repr'd.</li>
<li>BUGFIX: Fix to avoid writing '\r\r\n' on Windows when given a file opened in
text write mode ('w').</li>
</ul>
See <a class="reference internal" href="#string-interpolation-and-list-values">String Interpolation and List Values</a> for information about the problem with lists and interpolation.
</div>
<div class="section" id="version-4-7-1">
<h2><a class="toc-backref" href="#id93">20.2&nbsp;&nbsp;&nbsp;2010/02/06 - Version 4.7.1</a></h2>
<ul class="simple">
<li>Fix bug in options deprecation warning added in 4.7.0</li>
</ul>
</div>
<div class="section" id="version-4-7-0">
<h2><a class="toc-backref" href="#id94">20.3&nbsp;&nbsp;&nbsp;2010/01/09 - Version 4.7.0</a></h2>
<ul class="simple">
<li>Minimum supported version of Python is now 2.3</li>
<li>~25% performance improvement thanks to Christian Heimes</li>
<li>String interpolation now works in list value members</li>
<li>After validation any additional entries not in the configspec are listed in
the <tt class="docutils literal">extra_values</tt> section member</li>
<li>Addition of the <tt class="docutils literal">get_extra_values</tt> function for finding all extra values
in a validated ConfigObj instance</li>
<li>Deprecated the use of the <tt class="docutils literal">options</tt> dictionary in the ConfigObj constructor
and added explicit keyword arguments instead. Use **options if you want
to initialise a ConfigObj instance from a dictionary</li>
<li>Constructing a ConfigObj from an existing ConfigObj instance now preserves
the order of values and sections from the original instance in the new one</li>
<li>BUGFIX: Checks that failed validation would not populate <tt class="docutils literal">default_values</tt> and
<tt class="docutils literal">restore_default_value()</tt> wouldn't work for those entries</li>
<li>BUGFIX: clear() now clears 'defaults'</li>
<li>BUGFIX: empty values in list values were accidentally valid syntax. They now
raise a <tt class="docutils literal">ParseError</tt>. e.g. &quot;value = 1, , 2&quot;</li>
<li>BUGFIX: Change to the result of a call to <tt class="docutils literal">validate</tt> when <tt class="docutils literal">preserve_errors</tt>
is True. Previously sections where all values failed validation would
return False for the section rather than preserving the errors. False will
now only be returned for a section if it is missing</li>
<li>Distribution includes version 1.0.1 of validate.py</li>
<li>Removed __revision__ and __docformat__</li>
</ul>
</div>
<div class="section" id="version-4-6-0">
<h2><a class="toc-backref" href="#id95">20.4&nbsp;&nbsp;&nbsp;2009/04/13 - Version 4.6.0</a></h2>
<ul class="simple">
<li>Pickling of ConfigObj instances now supported (thanks to Christian Heimes)</li>
<li>Hashes in confgspecs are now allowed (see note below)</li>
<li>Replaced use of hasattr (which can swallow exceptions) with getattr</li>
<li>__many__ in configspecs can refer to scalars (ordinary values) as well as sections</li>
<li>You can use ___many___ (three underscores!) where you want to use __many__ as well</li>
<li>You can now have normal sections inside configspec sections that use __many__</li>
<li>You can now create an empty ConfigObj with a configspec, programmatically set values and then validate</li>
<li>A section that was supplied as a value (or vice-versa) in the actual config file would cause an exception during validation (the config file is still broken of course, but it is now handled gracefully)</li>
<li>Added <tt class="docutils literal">as_list</tt> method</li>
<li>Removed the deprecated <tt class="docutils literal">istrue</tt>, <tt class="docutils literal">encode</tt> and <tt class="docutils literal">decode</tt> methods</li>
<li>Running test_configobj.py now also runs the doctests in the configobj module</li>
</ul>
As a consequence of the changes to configspec handling, when you create a ConfigObj instance and provide
a configspec, the configspec attribute is only set on the ConfigObj instance - it isn't set on the
sections until you validate. You also can't set the configspec attribute to be a dictionary. This wasn't
documented but did work previously.
In order to fix the problem with hashes in configspecs I had to turn off the parsing of inline comments
in configspecs. This will only affect you if you are using <tt class="docutils literal">copy=True</tt> when validating and expecting
inline comments to be copied from the configspec into the ConfigObj instance (all other comments will be
copied as usual).
If you create the configspec by passing in a ConfigObj instance (usual way is to pass in a filename or
list of lines) then you should pass in <tt class="docutils literal">_inspec=True</tt> to the constructor to allow hashes in values.
This is the magic that switches off inline comment parsing.
</div>
<div class="section" id="version-4-5-3">
<h2><a class="toc-backref" href="#id96">20.5&nbsp;&nbsp;&nbsp;2008/06/27 - Version 4.5.3</a></h2>
BUGFIX: fixed a problem with <tt class="docutils literal">copy=True</tt> when validating with configspecs that use
<tt class="docutils literal">__many__</tt> sections.
</div>
<div class="section" id="version-4-5-2">
<h2><a class="toc-backref" href="#id97">20.6&nbsp;&nbsp;&nbsp;2008/02/05 - Version 4.5.2</a></h2>
Distribution updated to include version 0.3.2 of <a class="reference internal" href="#validate">validate</a>. This means that
<tt class="docutils literal">None</tt> as a default value in configspecs works.
</div>
<div class="section" id="version-4-5-1">
<h2><a class="toc-backref" href="#id98">20.7&nbsp;&nbsp;&nbsp;2008/02/05 - Version 4.5.1</a></h2>
Distribution updated to include version 0.3.1 of <a class="reference internal" href="#validate">validate</a>. This means that
Unicode configspecs now work.
</div>
<div class="section" id="version-4-5-0">
<h2><a class="toc-backref" href="#id99">20.8&nbsp;&nbsp;&nbsp;2008/02/05 - Version 4.5.0</a></h2>
ConfigObj will now guarantee that files will be written terminated with a
newline.
ConfigObj will no longer attempt to import the <tt class="docutils literal">validate</tt> module, until/unless
you call <tt class="docutils literal">ConfigObj.validate</tt> with <tt class="docutils literal">preserve_errors=True</tt>. This makes it
faster to import.
New methods <tt class="docutils literal">restore_default</tt> and <tt class="docutils literal">restore_defaults</tt>. <tt class="docutils literal">restore_default</tt>
resets an entry to its default value (and returns that value). <tt class="docutils literal">restore_defaults</tt>
resets all entries to their default value. It doesn't modify entries without a
default value. You must have validated a ConfigObj (which populates the
<tt class="docutils literal">default_values</tt> dictionary) before calling these methods.
BUGFIX: Proper quoting of keys, values and list values that contain hashes
(when writing). When <tt class="docutils literal">list_values=False</tt>, values containing hashes are
triple quoted.
Added the <tt class="docutils literal">reload</tt> method. This reloads a ConfigObj from file. If the filename
attribute is not set then a <tt class="docutils literal">ReloadError</tt> (a new exception inheriting from
<tt class="docutils literal">IOError</tt>) is raised.
BUGFIX: Files are read in with 'rb' mode, so that native/non-native line endings work!
Minor efficiency improvement in <tt class="docutils literal">unrepr</tt> mode.
Added missing docstrings for some overidden dictionary methods.
Added the <tt class="docutils literal">reset</tt> method. This restores a ConfigObj to a freshly created state.
Removed old CHANGELOG file.
</div>
<div class="section" id="version-4-4-0">
<h2><a class="toc-backref" href="#id100">20.9&nbsp;&nbsp;&nbsp;2007/02/04 - Version 4.4.0</a></h2>
Official release of 4.4.0
</div>
<div class="section" id="version-4-3-3-alpha4">
<h2><a class="toc-backref" href="#id101">20.10&nbsp;&nbsp;&nbsp;2006/12/17 - Version 4.3.3-alpha4</a></h2>
By Nicola Larosa
Allowed arbitrary indentation in the <tt class="docutils literal">indent_type</tt> parameter, removed the
<tt class="docutils literal">NUM_INDENT_SPACES</tt> and <tt class="docutils literal">MAX_INTERPOL_DEPTH</tt> (a leftover) constants,
added indentation tests (including another docutils workaround, sigh), updated
the documentation.
By Michael Foord
Made the import of <tt class="docutils literal">compiler</tt> conditional so that <tt class="docutils literal">ConfigObj</tt> can be used
with <a class="reference external" href="http://www.codeplex.com/IronPython">IronPython</a>.
</div>
<div class="section" id="version-4-3-3-alpha3">
<h2><a class="toc-backref" href="#id102">20.11&nbsp;&nbsp;&nbsp;2006/12/17 - Version 4.3.3-alpha3</a></h2>
By Nicola Larosa
Added a missing <tt class="docutils literal">self.</tt> in the _handle_comment method and a related test,
per Sourceforge bug #1523975.
</div>
<div class="section" id="version-4-3-3-alpha2">
<h2><a class="toc-backref" href="#id103">20.12&nbsp;&nbsp;&nbsp;2006/12/09 - Version 4.3.3-alpha2</a></h2>
By Nicola Larosa
Changed interpolation search strategy, based on this patch by Robin Munn:
<a class="reference external" href="http://sourceforge.net/mailarchive/message.php?msg_id=17125993">http://sourceforge.net/mailarchive/message.php?msg_id=17125993</a>
</div>
<div class="section" id="version-4-3-3-alpha1">
<h2><a class="toc-backref" href="#id104">20.13&nbsp;&nbsp;&nbsp;2006/12/09 - Version 4.3.3-alpha1</a></h2>
By Nicola Larosa
Added Template-style interpolation, with tests, based on this patch by
Robin Munn: <a class="reference external" href="http://sourceforge.net/mailarchive/message.php?msg_id=17125991">http://sourceforge.net/mailarchive/message.php?msg_id=17125991</a>
(awful archives, bad Sourceforge, bad).
</div>
<div class="section" id="version-4-3-2">
<h2><a class="toc-backref" href="#id105">20.14&nbsp;&nbsp;&nbsp;2006/06/04 - Version 4.3.2</a></h2>
Changed error handling, if parsing finds a single error then that error will
be re-raised. That error will still have an <tt class="docutils literal">errors</tt> and a <tt class="docutils literal">config</tt>
attribute.
Fixed bug where '\n' terminated files could be truncated.
Bugfix in <tt class="docutils literal">unrepr</tt> mode, it couldn't handle '#' in values. (Thanks to
Philippe Normand for the report.)
As a consequence of this fix, ConfigObj doesn't now keep inline comments in
<tt class="docutils literal">unrepr</tt> mode. This is because the parser in the <a class="reference external" href="http://docs.python.org/lib/compiler.html">compiler package</a>
doesn't keep comments.
Error messages are now more useful. They tell you the number of parsing errors
and the line number of the first error. (In the case of multiple errors.)
Line numbers in exceptions now start at 1, not 0.
Errors in <tt class="docutils literal">unrepr</tt> mode are now handled the same way as in the normal mode.
The errors stored will be an <tt class="docutils literal">UnreprError</tt>.
</div>
<div class="section" id="version-4-3-1">
<h2><a class="toc-backref" href="#id106">20.15&nbsp;&nbsp;&nbsp;2006/04/29 - Version 4.3.1</a></h2>
Added <tt class="docutils literal">validate.py</tt> back into <tt class="docutils literal">configobj.zip</tt>. (Thanks to Stewart
Midwinter)
Updated to <a class="reference external" href="http://www.voidspace.org.uk/downloads/validate.py">validate.py</a> 0.2.2.
Preserve tuples when calling the <tt class="docutils literal">dict</tt> method. (Thanks to Gustavo Niemeyer.)
Changed <tt class="docutils literal">__repr__</tt> to return a string that contains <tt class="docutils literal">ConfigObj({ ... })</tt>.
Change so that an options dictionary isn't modified by passing it to ConfigObj.
(Thanks to Artarious.)
Added ability to handle negative integers in <tt class="docutils literal">unrepr</tt>. (Thanks to Kevin
Dangoor.)
</div>
<div class="section" id="version-4-3-0">
<h2><a class="toc-backref" href="#id107">20.16&nbsp;&nbsp;&nbsp;2006/03/24 - Version 4.3.0</a></h2>
Moved the tests and the CHANGELOG (etc) into a separate file. This has reduced
the size of <tt class="docutils literal">configobj.py</tt> by about 40%.
Added the <tt class="docutils literal">unrepr</tt> mode to reading and writing config files. Thanks to Kevin
Dangoor for this suggestion.
Empty values are now valid syntax. They are read as an empty string <tt class="docutils literal">''</tt>.
(<tt class="docutils literal">key =</tt>, or <tt class="docutils literal">key = # comment</tt>.)
<tt class="docutils literal">validate</tt> now honours the order of the configspec.
Added the <tt class="docutils literal">copy</tt> mode to validate. Thanks to Louis Cordier for this
suggestion.
Fixed bug where files written on windows could be given <tt class="docutils literal">'\r\r\n'</tt> line
terminators.
Fixed bug where last occurring comment line could be interpreted as the
final comment if the last line isn't terminated.
Fixed bug where nested list values would be flattened when <tt class="docutils literal">write</tt> is
called. Now sub-lists have a string representation written instead.
Deprecated <tt class="docutils literal">encode</tt> and <tt class="docutils literal">decode</tt> methods instead.
You can now pass in a ConfigObj instance as a configspec (remember to read
the configspec file using <tt class="docutils literal">list_values=False</tt>).
Sorted footnotes in the docs.
</div>
<div class="section" id="version-4-2-0">
<h2><a class="toc-backref" href="#id108">20.17&nbsp;&nbsp;&nbsp;2006/02/16 - Version 4.2.0</a></h2>
Removed <tt class="docutils literal">BOM_UTF8</tt> from <tt class="docutils literal">__all__</tt>.
The <tt class="docutils literal">BOM</tt> attribute has become a boolean. (Defaults to <tt class="docutils literal">False</tt>.) It is
only <tt class="docutils literal">True</tt> for the <tt class="docutils literal">UTF16/UTF8</tt> encodings.
File like objects no longer need a <tt class="docutils literal">seek</tt> attribute.
Full unicode support added. New options/attributes <tt class="docutils literal">encoding</tt>,
<tt class="docutils literal">default_encoding</tt>.
ConfigObj no longer keeps a reference to file like objects. Instead the
<tt class="docutils literal">write</tt> method takes a file like object as an optional argument. (Which
will be used in preference of the <tt class="docutils literal">filename</tt> attribute if that exists as
well.)
utf16 files decoded to unicode.
If <tt class="docutils literal">BOM</tt> is <tt class="docutils literal">True</tt>, but no encoding specified, then the utf8 BOM is
written out at the start of the file. (It will normally only be <tt class="docutils literal">True</tt> if
the utf8 BOM was found when the file was read.)
Thanks to Aaron Bentley for help and testing on the unicode issues.
File paths are not converted to absolute paths, relative paths will
remain relative as the <tt class="docutils literal">filename</tt> attribute.
Fixed bug where <tt class="docutils literal">final_comment</tt> wasn't returned if <tt class="docutils literal">write</tt> is returning
a list of lines.
Deprecated <tt class="docutils literal">istrue</tt>, replaced it with <tt class="docutils literal">as_bool</tt>.
Added <tt class="docutils literal">as_int</tt> and <tt class="docutils literal">as_float</tt>.
</div>
<div class="section" id="version-4-1-0">
<h2><a class="toc-backref" href="#id109">20.18&nbsp;&nbsp;&nbsp;2005/12/14 - Version 4.1.0</a></h2>
Added <tt class="docutils literal">merge</tt>, a recursive update.
Added <tt class="docutils literal">preserve_errors</tt> to <tt class="docutils literal">validate</tt> and the <tt class="docutils literal">flatten_errors</tt>
example function.
Thanks to Matthew Brett for suggestions and helping me iron out bugs.
Fixed bug where a config file is all comment, the comment will now be
<tt class="docutils literal">initial_comment</tt> rather than <tt class="docutils literal">final_comment</tt>.
Validation no longer done on the 'DEFAULT' section (only in the root level).
This allows interpolation in configspecs.
Also use the new list syntax in <a class="reference internal" href="#validate">validate</a> 0.2.1. (For configspecs).
</div>
<div class="section" id="version-4-0-2">
<h2><a class="toc-backref" href="#id110">20.19&nbsp;&nbsp;&nbsp;2005/12/02 - Version 4.0.2</a></h2>
Fixed bug in <tt class="docutils literal">create_empty</tt>. Thanks to Paul Jimenez for the report.
</div>
<div class="section" id="version-4-0-1">
<h2><a class="toc-backref" href="#id111">20.20&nbsp;&nbsp;&nbsp;2005/11/05 - Version 4.0.1</a></h2>
Fixed bug in <tt class="docutils literal">Section.walk</tt> when transforming names as well as values.
Added the <tt class="docutils literal">istrue</tt> method. (Fetches the boolean equivalent of a string
value).
Fixed <tt class="docutils literal">list_values=False</tt> - they are now only quoted/unquoted if they
are multiline values.
List values are written as <tt class="docutils literal">item, item</tt> rather than <tt class="docutils literal">item,item</tt>.
</div>
<div class="section" id="version-4-0-0">
<h2><a class="toc-backref" href="#id112">20.21&nbsp;&nbsp;&nbsp;2005/10/17 - Version 4.0.0</a></h2>
ConfigObj 4.0.0 Final
Fixed bug in <tt class="docutils literal">setdefault</tt>. When creating a new section with setdefault the
reference returned would be to the dictionary passed in not to the new
section. Bug fixed and behaviour documented.
Obscure typo/bug fixed in <tt class="docutils literal">write</tt>. Wouldn't have affected anyone though.
</div>
<div class="section" id="version-4-0-0-beta-5">
<h2><a class="toc-backref" href="#id113">20.22&nbsp;&nbsp;&nbsp;2005/09/09 - Version 4.0.0 beta 5</a></h2>
Removed <tt class="docutils literal">PositionError</tt>.
Allowed quotes around keys as documented.
Fixed bug with commas in comments. (matched as a list value)
</div>
<div class="section" id="version-4-0-0-beta-4">
<h2><a class="toc-backref" href="#id114">20.23&nbsp;&nbsp;&nbsp;2005/09/07 - Version 4.0.0 beta 4</a></h2>
Fixed bug in <tt class="docutils literal">__delitem__</tt>. Deleting an item no longer deletes the
<tt class="docutils literal">inline_comments</tt> attribute.
Fixed bug in initialising ConfigObj from a ConfigObj.
Changed the mailing list address.
</div>
<div class="section" id="version-4-0-0-beta-3">
<h2><a class="toc-backref" href="#id115">20.24&nbsp;&nbsp;&nbsp;2005/08/28 - Version 4.0.0 beta 3</a></h2>
Interpolation is switched off before writing out files.
Fixed bug in handling <tt class="docutils literal">StringIO</tt> instances. (Thanks to report from
Gustavo Niemeyer.)
Moved the doctests from the <tt class="docutils literal">__init__</tt> method to a separate function.
(For the sake of IDE calltips).
</div>
<div class="section" id="version-4-0-0-beta-2">
<h2><a class="toc-backref" href="#id116">20.25&nbsp;&nbsp;&nbsp;2005/08/25 - Version 4.0.0 beta 2</a></h2>
Amendments to validate.py.
First public release.
</div>
<div class="section" id="version-4-0-0-beta-1">
<h2><a class="toc-backref" href="#id117">20.26&nbsp;&nbsp;&nbsp;2005/08/21 - Version 4.0.0 beta 1</a></h2>
Reads nested subsections to any depth.
Multiline values.
Simplified options and methods.
New list syntax.
Faster, smaller, and better parser.
Validation greatly improved. Includes:
<blockquote>
<ul class="simple">
<li>type conversion</li>
<li>default values</li>
<li>repeated sections</li>
</ul>
</blockquote>
Improved error handling.
Plus lots of other improvements.
</div>
<div class="section" id="version-3-0-0">
<h2><a class="toc-backref" href="#id118">20.27&nbsp;&nbsp;&nbsp;2004/05/24 - Version 3.0.0</a></h2>
Several incompatible changes: another major overhaul and change. (Lots of
improvements though).
Added support for standard config files with sections. This has an entirely
new interface: each section is a dictionary of values.
Changed the update method to be called writein: update clashes with a dict
method.
Made various attributes keyword arguments, added several.
Configspecs and orderlists have changed a great deal.
Removed support for adding dictionaries: use update instead.
Now subclasses a new class called caselessDict. This should add various
dictionary methods that could have caused errors before.
It also preserves the original casing of keywords when writing them back out.
Comments are also saved using a <tt class="docutils literal">caselessDict</tt>.
Using a non-string key will now raise a <tt class="docutils literal">TypeError</tt> rather than converting
the key.
Added an exceptions keyword for much better handling of errors.
Made <tt class="docutils literal">creatempty=False</tt> the default.
Now checks indict and any keyword args. Keyword args take precedence over
indict.
<tt class="docutils literal">' ', ':', '=', ','</tt> and <tt class="docutils literal">'\t'</tt> are now all valid dividers where the
keyword is unquoted.
ConfigObj now does no type checking against configspec when you set items.
delete and add methods removed (they were unnecessary).
Docs rewritten to include all this gumph and more; actually ConfigObj is
really easy to use.
Support for stdout was removed.
A few new methods added.
Charmap is now incorporated into ConfigObj.
</div>
<div class="section" id="version-2-0-0-beta">
<h2><a class="toc-backref" href="#id119">20.28&nbsp;&nbsp;&nbsp;2004/03/14 - Version 2.0.0 beta</a></h2>
Re-written it to subclass dict. My first forays into inheritance and operator
overloading.
The config object now behaves like a dictionary.
I've completely broken the interface, but I don't think anyone was really
using it anyway.
This new version is much more 'classy'.
It will also read straight from/to a filename and completely parse a config
file without you having to supply a config spec.
Uses listparse, so can handle nested list items as values.
No longer has getval and setval methods: use normal dictionary methods, or add
and delete.
</div>
<div class="section" id="version-1-0-5">
<h2><a class="toc-backref" href="#id120">20.29&nbsp;&nbsp;&nbsp;2004/01/29 - Version 1.0.5</a></h2>
Version 1.0.5 has a couple of bugfixes as well as a couple of useful additions
over previous versions.
Since 1.0.0 the buildconfig function has been moved into this distribution,
and the methods reset, verify, getval and setval have been added.
A couple of bugs have been fixed.
</div>
<div class="section" id="origins">
<h2><a class="toc-backref" href="#id121">20.30&nbsp;&nbsp;&nbsp;Origins</a></h2>
ConfigObj originated in a set of functions for reading config files in the
<a class="reference external" href="http://www.voidspace.org.uk/atlantibots/">atlantibots</a> project. The original
functions were written by Rob McNeur.
</div>
</div>
<hr class="docutils" />
<div class="section" id="footnotes">
<h1><a class="toc-backref" href="#id122">21&nbsp;&nbsp;&nbsp;Footnotes</a></h1>
<table class="docutils footnote" frame="void" id="id15" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id1">[1]</a></td><td>And if you discover any bugs, let us know. We'll fix them quickly.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id16" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id2">[2]</a></td><td>If you specify a filename that doesn't exist, ConfigObj will assume you
are creating a new one. See the create_empty and file_error options.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id17" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id3">[3]</a></td><td>They can be byte strings (ordinary strings) or Unicode.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id18" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id4">[4]</a></td><td>Except we don't support the RFC822 style line continuations, nor ':' as
a divider.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id19" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id5">[5]</a></td><td>This is a change in ConfigObj 4.2.0. Note that ConfigObj doesn't call
the seek method of any file like object you pass in. You may want to call
<tt class="docutils literal">file_object.seek(0)</tt> yourself, first.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id20" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id6">[6]</a></td><td>A side effect of this is that it enables you to copy a ConfigObj :
<div class="highlight"><pre># only copies members
# not attributes/comments
config2 = ConfigObj(config1)
</pre></div>
Since ConfigObj 4.7.0 the order of members and sections will be
preserved when copying a ConfigObj instance.
</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id21" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id7">[7]</a></td><td>Other than lists of strings.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id22" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id8">[8]</a></td><td>The exception is if it detects a <tt class="docutils literal">UTF16</tt> encoded file which it
must decode before parsing.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id23" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id9">[9]</a></td><td>The method signature shows that this method takes
two arguments. The second is the section to be written. This is because the
<tt class="docutils literal">write</tt> method is called recursively.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id24" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id10">[10]</a></td><td>The dict method doesn't actually use the deepcopy mechanism. This means
if you add nested lists (etc) to your ConfigObj, then the dictionary
returned by dict may contain some references. For all normal ConfigObjs
it will return a deepcopy.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id25" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id11">[11]</a></td><td>Passing <tt class="docutils literal">(section, key)</tt> rather than <tt class="docutils literal">(value, key)</tt> allows you to
change the value by setting <tt class="docutils literal">section[key] = newval</tt>. It also gives you
access to the rename method of the section.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id26" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id12">[12]</a></td><td>Minimum required version of validate.py 0.2.0 .</td></tr>
</tbody>
</table>
</div>
</div>
</body>
</html>