Development Guidelines

Coding Guidelines

For all the code in Sahara we have a rule - it should pass PEP 8.

To check your code against PEP 8 run:

$ tox -e pep8

Note

For more details on coding guidelines see file HACKING.rst in the root of Sahara repo.

Modification of Upstream Files

We never modify upstream files in Sahara. Any changes in upstream files should be made in the upstream project and then merged back in to Sahara. This includes whitespace changes, comments, and typos. Any change requests containing upstream file modifications are almost certain to receive lots of negative reviews. Be warned.

Examples of upstream files are default xml configuration files used to configure Hadoop, or code imported from the OpenStack Oslo project. The xml files will usually be found in resource directories with an accompanying README file that identifies where the files came from. For example:

$ pwd
/home/me/sahara/sahara/plugins/vanilla/v2_3_0/resources

$ ls
core-default.xml     hdfs-default.xml    oozie-default.xml   README.rst
create_oozie_db.sql  mapred-default.xml  post_conf.template  yarn-default.xml

Testing Guidelines

Sahara has a suite of tests that are run on all submitted code, and it is recommended that developers execute the tests themselves to catch regressions early. Developers are also expected to keep the test suite up-to-date with any submitted code changes.

Unit tests are located at sahara/tests.

Sahara’s suite of unit tests can be executed in an isolated environment with Tox. To execute the unit tests run the following from the root of Sahara repo:

$ tox -e py27

Documentation Guidelines

All Sahara docs are written using Sphinx / RST and located in the main repo in doc directory. You can add/edit pages here to update http://docs.openstack.org/developer/sahara site.

The documentation in docstrings should follow the PEP 257 conventions (as mentioned in the PEP 8 guidelines).

More specifically:

1. Triple quotes should be used for all docstrings.
2. If the docstring is simple and fits on one line, then just use one line.
3. For docstrings that take multiple lines, there should be a newline after the opening quotes, and before the closing quotes.
4. Sphinx is used to build documentation, so use the restructured text markup to designate parameters, return values, etc. Documentation on the sphinx specific markup can be found here:

Run the following command to build docs locally.

$ tox -e docs

After it you can access generated docs in doc/build/ directory, for example, main page - doc/build/html/index.html.

To make docs generation process faster you can use:

$ SPHINX_DEBUG=1 tox -e docs

or to avoid sahara reinstallation to virtual env each time you want to rebuild docs you can use the following command (it could be executed only after running tox -e docs first time):

$ SPHINX_DEBUG=1 .tox/docs/bin/python setup.py build_sphinx

Note

For more details on documentation guidelines see file HACKING.rst in the root of Sahara repo.