Python library for parsing configuration files with conditionals
CondConfigParser is a Python library designed to help Python application developers to parse configuration files. Compared to well-known modules such as configparser and json, the main specificity of CondConfigParser is that it allows the end user to define conditions using boolean operators and specific sections in the configuration file that are only applied when the corresponding condition is fulfilled.
The configuration file format allows the end user to define variables of type boolean, string or list. These variables, in addition to external variables defined by the application, can be combined with Python-like syntax to define the conditions (called predicates) mentioned in the previous paragraph.
Lists in CondConfigParser may be nested at will. Variable definitions
may refer to previously-defined variables. Predicates can combine
in tests using as many logical
not operators and parentheses as necessary. Such “logical
expressiveness” (and much more) could be obtained by reading
configuration files interpreted as Python code, however:
- the syntax in such a case would not allow the almost-freeform options that are permitted by CondConfigParser (where the application chooses how to interpret the “options”);
- when an application interprets user configuration files as Python code, it exposes its users to some risk in case a malicious user manages to sneak code of his choice into a configuration file of the victim (think about configuration file snippets copied from Internet forums...).
Regarding the second point in particular, CondConfigParser never uses
exec to parse configuration files. It should thus be
safe to work with any configuration file, including files prepared by
CondConfigParser's home page is located at:
(it was on people.via.ecp.fr before April 30, 2016)
This version of CondConfigParser requires Python 3.4 or later.
Installation from source also requires setuptools, but this should only
be a concern if you want to install without pip (if you have
you should already have
setuptools; and if not, installing
is likely to cause
setuptools to be installed at the same time).
If you are a Debian user, you can install CondConfigParser using the
following lines in your
deb http://frougon.net/debian-ffgo unstable main deb-src http://frougon.net/debian-ffgo unstable main
The package is named
python3-condconfigparser. A package for Debian
stable is also available. If this is what you want, just replace
unstable with jessie, or whatever is the codename of the current
Debian stable release, in the
sources.list lines given above.
Quick installation instructions
This section describes installation from source. If you want to install from a Debian package instead, see above.
If you have a working pip setup, you should be able to install CondConfigParser with:
pip install CondConfigParser
pip install condconfigparser also works)
When doing so, make sure that your
pip executable runs with the
Python 3 installation you want to install CondConfigParser for.
For more detailed instructions, you can read the
from a release tarball. You may also want to consult the “Installing
Python Modules” chapter of the Python documentation and the pip
Typical installations with pip automatically download the latest release from PyPI. However, in some cases, you may want to download the tarball or zip file yourself in order to install it later, possibly on a different machine. In such a case, you may get it from PyPI or from Florent Rougon's home page.
CondConfigParser is maintained in a Git repository that can be cloned with:
git clone https://github.com/frougon/CondConfigParser
The CondConfigParser Manual is written in reStructuredText format for the Sphinx documentation generator. The HTML documentation for the latest version of CondConfigParser as rendered by Sphinx is available at:
The sources for the CondConfigParser Manual are located in the
top-level directory of the CondConfigParser distribution, but the
documentation build process pulls many parts from the source code,
To generate the documentation yourself from CondConfigParser's code and
the reStructuredText sources in the
doc directory, first make
sure you have Python 3.x, Sphinx and Make installed. Then, go
doc directory and type, for instance:
You will find the output in the
_build/html subdirectory of
Sphinx can build the documentation in many other formats. For
instance, if you have LaTeX installed, you can generate the
CondConfigParser Manual in PDF format with:
You can run
make from the
doc directory to see a list of the
available formats. Run
make clean to clean up after the
documentation build process.
Makefileuses a Python script (
prepare-basic-pkg-info.py) to generate
basic-pkg-info.rstfrom the top-level
README.rstfile. By default, this script is interpreted by the
python3executable. If you want to explicitely choose the interpreter to use, you can set the
PYTHONMakefile variable like this:make PYTHON=python3.4 html
Note that this only affects running of
prepare-basic-pkg-info.py; the Python interpreter used by Sphinx in other places of the
Makefileis determined by the sphinx-build executable that should be part of your Sphinx installation.
python3 prepare-basic-pkg-info.py ../README.rst basic-pkg-info.rst sphinx-build -b html -d _build/doctrees . _build/html
These commands must be run from the
doc directory. Please refer to
sphinx-build for more details.
Running the automated test suite
If you want to run the automated test suite from an unpacked release tarball (or Git checkout), go to the root directory of that CondConfigParser distribution (the directory containing
condconfigparserdirectory) and run:
python3 -m unittest
(assuming of course that you want to run the tests with an executable called
You may want to add the
-voption at the end of the command in order to run the test suite in verbose mode.
On the other hand, if you have already installed CondConfigParser for a given Python installation and you want to test the installed package, go to the directory containing the installed package and run:
python3 -m unittest discover -t ..
With a POSIX-style shell, you can combine both operations with the following command (that does not change your current directory):
( cd base_dir/lib/python3.4/site-packages/condconfigparser && \ python3 -m unittest discover -t .. )
This command is given for a Python 3.4 installation:
You may want to add the
-voption after the
discoverargument in order to run the test suite in verbose mode.
A successful run of the test suite looks like this:
% python3 -m unittest ....... ---------------------------------------------------------------------- Ran 7 tests in 0.052s OK % echo $? 0 %
In the above output, each dot represents a successful test. The
echo $? command shows the zero exit status, indicating success for
all tests. In case of a failure, the exit status is non-zero.
python3 setup.py test