Getting started¶
Working on cryptography requires the installation of a small number of development dependencies in addition to the dependencies for Installation. These are listed in dev-requirements.txt and they can be installed in a virtualenv using pip. Once you’ve installed the dependencies, install cryptography in editable mode. For example:
$ # Create a virtualenv and activate it
$ pip install --requirement dev-requirements.txt
$ pip install --editable .
You will also need to install enchant using your system’s package manager to check spelling in the documentation.
You are now ready to run the tests and build the documentation.
Running tests¶
cryptography unit tests are found in the tests/ directory and are designed to be run using pytest. pytest will discover the tests automatically, so all you have to do is:
$ py.test
...
62746 passed in 220.43 seconds
This runs the tests with the default Python interpreter.
You can also verify that the tests pass on other supported Python interpreters. For this we use tox, which will automatically create a virtualenv for each supported Python version and run the tests. For example:
$ tox
...
ERROR: py26: InterpreterNotFound: python2.6
py27: commands succeeded
ERROR: pypy: InterpreterNotFound: pypy
py33: commands succeeded
docs: commands succeeded
pep8: commands succeeded
You may not have all the required Python versions installed, in which case you will see one or more InterpreterNotFound errors.
Explicit backend selection¶
While testing you may want to run tests against a subset of the backends that cryptography supports. Explicit backend selection can be done via the --backend flag. This flag should be passed to py.test with a comma delimited list of backend names.
$ tox -- --backend=openssl
$ py.test --backend=openssl,commoncrypto
Building documentation¶
cryptography documentation is stored in the docs/ directory. It is written in reStructured Text and rendered using Sphinx.
Use tox to build the documentation. For example:
$ tox -e docs
...
docs: commands succeeded
congratulations :)
The HTML documentation index can now be found at docs/_build/html/index.html.