<li><p class="first">Integrated with a powerful validation system</p>
<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><p class="first">When writing out config files, ConfigObj preserves all comments and the order of members and sections</p>
</li>
<li><p class="first">Many useful methods and options for working with configuration files (like the 'reload' method)</p>
</li>
<li><p class="first">Full Unicode support</p>
</li>
</ul>
<p>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
<p><em>configobj.zip</em> also contains <a class="reference external" href="http://www.voidspace.org.uk/python/configobj.html">this document</a>.</p>
<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 Development Version</a></h2>
<p>It is sometimes possible to get the latest <em>development version</em> of ConfigObj
from the Subversion Repository maintained on the <a class="reference external" href="http://code.google.com/p/configobj/">Google Code Homepage</a>.</p>
<p>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>.</p>
</blockquote>
</li>
<li><p class="first"><a class="reference external" href="http://elisa.fluendo.com/">Elisa - the Fluendo Mediacenter</a></p>
<blockquote>
<p>Elisa is an open source cross-platform media center solution designed to be simple for people not particularly familiar with computers.</p>
<p>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>.</p>
<p class="last">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>.</p>
<p>You don't need to specify an infile. If you omit it, an empty ConfigObj will be
created. <tt class="docutils literal">infile</tt> <em>can</em> be :</p>
<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>
<p>If you use the validation scheme, it can do type checking <em>and</em> conversion
for you. This means you may want to set members to integers, or other
non-string values.</p>
<p>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.</p>
<p>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
<p>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.)</p>
<p>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.</p>
<!-- note:
Even if all the keys in a section are in the defaults list, the section
marker is still written out. -->
<p>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>.</p>
<div class="note">
<p class="first admonition-title">Note</p>
<p class="last">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.</p>
</div>
<p>The default value can be a list. See <a class="reference internal" href="#id13">List Values</a> for the way to do this.</p>
<p>Writing invalid default values is a <em>guaranteed</em> way of confusing your users.
Default values <strong>must</strong> pass the check.</p>
<p>ConfigObj can perform string interpolation in a <em>similar</em> way to
<tt class="docutils literal">ConfigParser</tt>. See the <a class="reference internal" href="#string-interpolation">String Interpolation</a> section for full details.</p>
<p>If <tt class="docutils literal">interpolation</tt> is set to <tt class="docutils literal">False</tt>, then interpolation is <em>not</em> done when
<p>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.</p>
<p>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>.</p>
<p>If the initial config file <em>started</em> 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>.</p>
<p>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> <em>or</em> to <tt class="docutils literal">utf_8</tt> (and variants) a UTF BOM will be written.</p>
<p>For UTF16 encodings, a BOM is <em>always</em> written.</p>
<p>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.</p>
<p>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.</p>
<p>For example you could use the <tt class="docutils literal">LineParser</tt> from the
<p>Single line values aren't quoted when writing - but multiline values are
handled as normal.</p>
<div class="caution">
<p class="first admonition-title">Caution!</p>
<p class="last">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 <em>could</em> now be incompatible and need the quotes removing by hand.</p>
<p>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.</p>
</div>
</div>
</div>
<div class="section" id="the-config-file-format">
<h1><a class="toc-backref" href="#id60">6 The Config File Format</a></h1>
<p>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.</p>
<p>The basic pattern for keywords is:</p>
<pre class="literal-block">
# comment line
# comment line
keyword = value # inline comment
</pre>
<p>Both keyword and value can optionally be surrounded in quotes. The equals sign
is the only valid divider.</p>
<p>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.</p>
<p>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.</p>
<p>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:</p>
<pre class="literal-block">
keyword1 = value1, value2, value3
keyword2 = value1, # a single member list
keyword3 = , # an empty list
</pre>
<p>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:</p>
<pre class="literal-block">
keyword1 = ''' A multi line value
on several
lines''' # with a comment
keyword2 = '''I won't be "afraid".'''
#
keyword3 = """ A multi line value
on several
lines""" # with a comment
keyword4 = """I won't be "afraid"."""
</pre>
<div class="warning">
<p class="first admonition-title">Warning</p>
<p class="last">There is no way of safely quoting values that contain both types of triple
quotes.</p>
</div>
<p>A line that starts with a '#', possibly preceded by whitespace, is a comment.</p>
<p>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:</p>
<pre class="literal-block">
# The First Section
[ section name 1 ] # first section
keyword1 = value1
# The Second Section
[ "section name 2" ] # second section
keyword2 = value2
</pre>
<p>Any subsections (sections that are <em>inside</em> 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.</p>
<p>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.</p>
<p>A <em>NestingError</em> 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.</p>
<p>In the outer section, single values can only appear before any sub-section.
Otherwise they will belong to the sub-section immediately before them:</p>
<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>
<p>When parsed, the above config file produces the following data structure:</p>
<p class="last">If you now change <tt class="docutils literal">vals</tt>, the changes won't be reflected in <tt class="docutils literal"><span class="pre">config['vals']</span></tt>.</p>
</div>
<p>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.</p>
<ul>
<li><p class="first">'__iter__'</p>
<blockquote>
<p>More commonly known as <tt class="docutils literal">for member in section:</tt>.</p>
</blockquote>
</li>
<li><p class="first">'__repr__' and '__str__'</p>
<blockquote>
<p>Any time you print or display the ConfigObj.</p>
<p>A reference to the 'parent' section, the section that this section is a
member of.</p>
<p>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>.</p>
</blockquote>
</li>
<li><p class="first">depth</p>
<blockquote>
<p>The nesting level of the current section.</p>
<p>If you create a new ConfigObj and add sections, 1 will be added to the
depth level between sections.</p>
</blockquote>
</li>
<li><p class="first">defaults</p>
<blockquote>
<p>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.</p>
</blockquote>
</li>
<li><p class="first">default_values</p>
<blockquote>
<p>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.</p>
</blockquote>
</li>
<li><p class="first">scalars, sections</p>
<blockquote>
<p>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, <em>or</em> the order that you added
members.</p>
<p>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.</p>
<p>Adding or removing members also alters these lists. You can manipulate the
lists directly to alter the order of members.</p>
<div class="warning">
<p class="first admonition-title">Warning</p>
<p class="last">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.</p>
</div>
<p>See also the <tt class="docutils literal">rename</tt> method.</p>
</blockquote>
</li>
<li><p class="first">comments</p>
<blockquote>
<p>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.</p>
</blockquote>
</li>
<li><p class="first">inline_comments</p>
<blockquote>
<p>This is <em>another</em> dictionary of comments associated with each member. Each
entry is a string that is put inline with the member.</p>
</blockquote>
</li>
<li><p class="first">configspec</p>
<blockquote>
<p>The configspec attribute is a dictionary mapping scalars to <em>checks</em>. A
check defines the expected type and possibly the allowed values for a
member.</p>
<p>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.</p>
<p>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).</p>
<p>You can set the configspec attribute directly on a section.</p>
<p>See the <a class="reference internal" href="#validation">validation</a> section for full details of how to write configspecs.</p>
</blockquote>
</li>
<li><p class="first">extra_values</p>
<blockquote>
<p>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.</p>
<p><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.</p>
<p>It walks through every member and calls a function on the keyword and value. It
walks recursively through subsections.</p>
<p>It returns a dictionary of all the computed values.</p>
<p>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.</p>
<p>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.</p>
<p>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, <em>first</em> the function is called for the <em>whole</em>
sub-section, and <em>then</em> it recurses into it's members. This means your function
must be able to handle receiving dictionaries as well as strings and lists.</p>
<p>If you are using the return value from <tt class="docutils literal">walk</tt> <em>and</em> <tt class="docutils literal">call_on_sections</tt>,
note that walk discards the return value when it calls your function.</p>
<div class="caution">
<p class="first admonition-title">Caution!</p>
<p class="last">You can use <tt class="docutils literal">walk</tt> to transform the names of members of a section
<p>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.</p>
<p>Another thing you might want to do is use the Python escape codes in your
values. You might be <em>used</em> 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.</p>
<p>As an example we'll write a function to use with walk, that encodes or decodes
values using the <tt class="docutils literal"><span class="pre">string-escape</span></tt> codec.</p>
<p>The function has to take each value and set the new value. As a bonus we'll
create one function that will do decode <em>or</em> encode depending on a keyword
argument.</p>
<p>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).</p>
<p>We're not using the return values, so it doesn't need to return anything, just
<p>There are several places where ConfigObj may raise exceptions (other than
because of bugs).</p>
<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><p class="first last">filename doesn't exist <em>and</em> <tt class="docutils literal">file_error=True</tt>, an <tt class="docutils literal">IOError</tt> will be
raised.</p>
</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><p class="first last"><tt class="docutils literal">stringify=False</tt>, a <tt class="docutils literal">TypeError</tt> will be raised.</p>
</dd>
</dl>
</li>
<li><p class="first">A badly built config file will cause parsing errors.</p>
</li>
<li><p class="first">A parsing error can also occur when reading a configspec.</p>
</li>
<li><dl class="first docutils">
<dt>In string interpolation you can specify a value that doesn't exist, or</dt>
<p>The system of configspecs can seem confusing at first, but is actually
quite simple and powerful. The best reference is my article on ConfigObj:</p>
<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>
<p>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 <em>validate.py</em> <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.</p>
<p>Validation can perform two different operations :</p>
<ol class="arabic">
<li><dl class="first docutils">
<dt>Check that a value meets a specification. For example, check that a value</dt>
<dd><p class="first last">is an integer between one and six, or is a choice from a specific set of
options.</p>
</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><p class="first last">your values is a port number, validation will turn it into an integer for
you.</p>
</dd>
</dl>
</li>
</ol>
<p>So validation can act as a transparent layer between the datatypes of your
application configuration (boolean, integers, floats, etc) and the text format
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>The basic datatypes that an un-extended Validator can test for are :</p>
<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>
<p>It can also handle lists of these types and restrict a value to being one from
a set of options.</p>
<p>An example configspec is going to look something like:</p>
<pre class="literal-block">
port = integer(0, 100)
user = string(max=25)
mode = option('quiet', 'loud', 'silent')
</pre>
<p>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>.</p>
<p>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>.</p>
<div class="important">
<p class="first admonition-title">Important</p>
<p>Your configspec is read by ConfigObj in the same way as a config file.</p>
<p>That means you can do interpolation <em>within</em> your configspec.</p>
<p>In order to allow this, checks in the 'DEFAULT' section (of the root level
of your configspec) are <em>not</em> used.</p>
<p>If you want to use a configspec <em>without</em> interpolation being done in it
you can create your configspec manually and switch off interpolation:</p>
<h2><a class="toc-backref" href="#id69">9.2 Type Conversion</a></h2>
<p>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).</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>If you <em>don't</em> 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.</p>
<p>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) <em>whichever check is used</em>. (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.</p>
<p>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
<p>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:</p>
<pre class="literal-block">
Copyright (c) 2004 - 2010, Michael Foord & 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
"AS IS" 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>
<p>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></p>
<p class="last">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 <strong>ConfigObj</strong>
<p>There is currently no way to specify the encoding of a configspec file.</p>
<p>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.</p>
<p>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).</p>
<p>If you <em>create</em> 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.</p>
<p>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 <em>can</em> use interpolation in configspec
files. This is probably true even if interpolation is off in the
configspec.</p>
<p>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.</p>
<p>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).</p>
<p>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.</p>
<p>Does it matter that we don't support the ':' divider, which is supported
by <tt class="docutils literal">ConfigParser</tt> ?</p>
<p>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
<p>This is an abbreviated changelog showing the major releases up to version 4.
From version 4 it lists all releases and changes.</p>
<div class="section" id="version-4-7-2">
<h2><a class="toc-backref" href="#id92">20.1 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>
<p>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.</p>
</div>
<div class="section" id="version-4-7-1">
<h2><a class="toc-backref" href="#id93">20.2 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 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. "value = 1, , 2"</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 <em>all</em> 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 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>
<h2><a class="toc-backref" href="#id104">20.13 2006/12/09 - Version 4.3.3-alpha1</a></h2>
<p>By Nicola Larosa</p>
<p>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).</p>
</div>
<div class="section" id="version-4-3-2">
<h2><a class="toc-backref" href="#id105">20.14 2006/06/04 - Version 4.3.2</a></h2>
<p>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.</p>
<p>Fixed bug where '\n' terminated files could be truncated.</p>
<p>Bugfix in <tt class="docutils literal">unrepr</tt> mode, it couldn't handle '#' in values. (Thanks to
Philippe Normand for the report.)</p>
<p>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.</p>
<p>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.)</p>
<p>Line numbers in exceptions now start at 1, not 0.</p>
<p>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>.</p>
</div>
<div class="section" id="version-4-3-1">
<h2><a class="toc-backref" href="#id106">20.15 2006/04/29 - Version 4.3.1</a></h2>
<p>Added <tt class="docutils literal">validate.py</tt> back into <tt class="docutils literal">configobj.zip</tt>. (Thanks to Stewart
Midwinter)</p>
<p>Updated to <a class="reference external" href="http://www.voidspace.org.uk/downloads/validate.py">validate.py</a> 0.2.2.</p>
<p>Preserve tuples when calling the <tt class="docutils literal">dict</tt> method. (Thanks to Gustavo Niemeyer.)</p>
<p>Changed <tt class="docutils literal">__repr__</tt> to return a string that contains <tt class="docutils literal">ConfigObj({ ... })</tt>.</p>
<p>Change so that an options dictionary isn't modified by passing it to ConfigObj.
(Thanks to Artarious.)</p>
<p>Added ability to handle negative integers in <tt class="docutils literal">unrepr</tt>. (Thanks to Kevin
Dangoor.)</p>
</div>
<div class="section" id="version-4-3-0">
<h2><a class="toc-backref" href="#id107">20.16 2006/03/24 - Version 4.3.0</a></h2>
<p>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%.</p>
<p>Added the <tt class="docutils literal">unrepr</tt> mode to reading and writing config files. Thanks to Kevin
Dangoor for this suggestion.</p>
<p>Empty values are now valid syntax. They are read as an empty string <tt class="docutils literal">''</tt>.
<p>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.)</p>
<p>utf16 files decoded to unicode.</p>
<p>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.)</p>
<p>Thanks to Aaron Bentley for help and testing on the unicode issues.</p>
<p>File paths are <em>not</em> converted to absolute paths, relative paths will
remain relative as the <tt class="docutils literal">filename</tt> attribute.</p>
<p>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.</p>
<p>Deprecated <tt class="docutils literal">istrue</tt>, replaced it with <tt class="docutils literal">as_bool</tt>.</p>
<p>Added <tt class="docutils literal">as_int</tt> and <tt class="docutils literal">as_float</tt>.</p>
</div>
<div class="section" id="version-4-1-0">
<h2><a class="toc-backref" href="#id109">20.18 2005/12/14 - Version 4.1.0</a></h2>
<p>Added <tt class="docutils literal">merge</tt>, a recursive update.</p>
<p>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.</p>
<p>Thanks to Matthew Brett for suggestions and helping me iron out bugs.</p>
<p>Fixed bug where a config file is <em>all</em> comment, the comment will now be
<tt class="docutils literal">initial_comment</tt> rather than <tt class="docutils literal">final_comment</tt>.</p>
<p>Validation no longer done on the 'DEFAULT' section (only in the root level).
This allows interpolation in configspecs.</p>
<p>Also use the new list syntax in <a class="reference internal" href="#validate">validate</a> 0.2.1. (For configspecs).</p>
</div>
<div class="section" id="version-4-0-2">
<h2><a class="toc-backref" href="#id110">20.19 2005/12/02 - Version 4.0.2</a></h2>
<p>Fixed bug in <tt class="docutils literal">create_empty</tt>. Thanks to Paul Jimenez for the report.</p>
</div>
<div class="section" id="version-4-0-1">
<h2><a class="toc-backref" href="#id111">20.20 2005/11/05 - Version 4.0.1</a></h2>
<p>Fixed bug in <tt class="docutils literal">Section.walk</tt> when transforming names as well as values.</p>
<p>Added the <tt class="docutils literal">istrue</tt> method. (Fetches the boolean equivalent of a string
value).</p>
<p>Fixed <tt class="docutils literal">list_values=False</tt> - they are now only quoted/unquoted if they
are multiline values.</p>
<p>List values are written as <tt class="docutils literal">item, item</tt> rather than <tt class="docutils literal">item,item</tt>.</p>
</div>
<div class="section" id="version-4-0-0">
<h2><a class="toc-backref" href="#id112">20.21 2005/10/17 - Version 4.0.0</a></h2>
<p><strong>ConfigObj 4.0.0 Final</strong></p>
<p>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 <em>not</em> to the new
section. Bug fixed and behaviour documented.</p>
<p>Obscure typo/bug fixed in <tt class="docutils literal">write</tt>. Wouldn't have affected anyone though.</p>
</div>
<div class="section" id="version-4-0-0-beta-5">
<h2><a class="toc-backref" href="#id113">20.22 2005/09/09 - Version 4.0.0 beta 5</a></h2>
<p>Fixed bug in initialising ConfigObj from a ConfigObj.</p>
<p>Changed the mailing list address.</p>
</div>
<div class="section" id="version-4-0-0-beta-3">
<h2><a class="toc-backref" href="#id115">20.24 2005/08/28 - Version 4.0.0 beta 3</a></h2>
<p>Interpolation is switched off before writing out files.</p>
<p>Fixed bug in handling <tt class="docutils literal">StringIO</tt> instances. (Thanks to report from
Gustavo Niemeyer.)</p>
<p>Moved the doctests from the <tt class="docutils literal">__init__</tt> method to a separate function.
(For the sake of IDE calltips).</p>
</div>
<div class="section" id="version-4-0-0-beta-2">
<h2><a class="toc-backref" href="#id116">20.25 2005/08/25 - Version 4.0.0 beta 2</a></h2>
<p>Amendments to <em>validate.py</em>.</p>
<p>First public release.</p>
</div>
<div class="section" id="version-4-0-0-beta-1">
<h2><a class="toc-backref" href="#id117">20.26 2005/08/21 - Version 4.0.0 beta 1</a></h2>
<p>Reads nested subsections to any depth.</p>
<p>Multiline values.</p>
<p>Simplified options and methods.</p>
<p>New list syntax.</p>
<p>Faster, smaller, and better parser.</p>
<p>Validation greatly improved. Includes:</p>
<blockquote>
<ul class="simple">
<li>type conversion</li>
<li>default values</li>
<li>repeated sections</li>
</ul>
</blockquote>
<p>Improved error handling.</p>
<p>Plus lots of other improvements.</p>
</div>
<div class="section" id="version-3-0-0">
<h2><a class="toc-backref" href="#id118">20.27 2004/05/24 - Version 3.0.0</a></h2>
<p>Several incompatible changes: another major overhaul and change. (Lots of
improvements though).</p>
<p>Added support for standard config files with sections. This has an entirely
new interface: each section is a dictionary of values.</p>
<p>Changed the update method to be called writein: update clashes with a dict
method.</p>
<p>Made various attributes keyword arguments, added several.</p>
<p>Configspecs and orderlists have changed a great deal.</p>
<p>Removed support for adding dictionaries: use update instead.</p>
<p>Now subclasses a new class called caselessDict. This should add various
dictionary methods that could have caused errors before.</p>
<p>It also preserves the original casing of keywords when writing them back out.</p>
<p>Comments are also saved using a <tt class="docutils literal">caselessDict</tt>.</p>
<p>Using a non-string key will now raise a <tt class="docutils literal">TypeError</tt> rather than converting
the key.</p>
<p>Added an exceptions keyword for <em>much</em> better handling of errors.</p>
<p>Made <tt class="docutils literal">creatempty=False</tt> the default.</p>
<p>Now checks indict <em>and</em> any keyword args. Keyword args take precedence over
indict.</p>
<p><tt class="docutils literal">' ', <span class="pre">':',</span> <span class="pre">'=',</span> ','</tt> and <tt class="docutils literal">'\t'</tt> are now all valid dividers where the
keyword is unquoted.</p>
<p>ConfigObj now does no type checking against configspec when you set items.</p>
<p>delete and add methods removed (they were unnecessary).</p>
<p>Docs rewritten to include all this gumph and more; actually ConfigObj is
<em>really</em> easy to use.</p>
<p>Support for stdout was removed.</p>
<p>A few new methods added.</p>
<p>Charmap is now incorporated into ConfigObj.</p>
</div>
<div class="section" id="version-2-0-0-beta">
<h2><a class="toc-backref" href="#id119">20.28 2004/03/14 - Version 2.0.0 beta</a></h2>
<p>Re-written it to subclass dict. My first forays into inheritance and operator
overloading.</p>
<p>The config object now behaves like a dictionary.</p>
<p>I've completely broken the interface, but I don't think anyone was really
using it anyway.</p>
<p>This new version is much more 'classy'.</p>
<p>It will also read straight from/to a filename and completely parse a config
file without you <em>having</em> to supply a config spec.</p>
<p>Uses listparse, so can handle nested list items as values.</p>
<p>No longer has getval and setval methods: use normal dictionary methods, or add
and delete.</p>
</div>
<div class="section" id="version-1-0-5">
<h2><a class="toc-backref" href="#id120">20.29 2004/01/29 - Version 1.0.5</a></h2>
<p>Version 1.0.5 has a couple of bugfixes as well as a couple of useful additions
over previous versions.</p>
<p>Since 1.0.0 the buildconfig function has been moved into this distribution,
and the methods reset, verify, getval and setval have been added.</p>
<tr><td class="label"><a class="fn-backref" href="#id6">[6]</a></td><td><p class="first">A side effect of this is that it enables you to copy a ConfigObj :</p>
<div class="highlight"><pre><span class="c"># only copies members</span>
<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
<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 <em>rename</em> method of the section.</td></tr>
