salt/CONTRIBUTING.rst

============
Contributing
============


So you want to contribute to the Salt project? Excellent! You can help
in a number of ways:

-  Using Salt and opening well-written bug reports.
-  Joining a `working group <https://github.com/saltstack/community>`__.
-  Answering questions on `irc <https://webchat.freenode.net/#salt>`__,
   the `community Slack <https://join.slack.com/t/saltstackcommunity/shared_invite/zt-3av8jjyf-oBQ2M0vhXOhJpNpRkPWBvg>`__,
   the `salt-users mailing
   list <https://groups.google.com/forum/#!forum/salt-users>`__,
   `Server Fault <https://serverfault.com/questions/tagged/saltstack>`__,
   or `r/saltstack on Reddit <https://www.reddit.com/r/saltstack/>`__.
-  Fixing bugs.
-  `Enhancing the documentation <https://docs.saltproject.io/en/master/topics/development/conventions/documentation.html#salt-docs>`__.
- Providing workarounds, patches, or other code without tests.
- Telling other people about problems you solved using Salt.

If you’d like to update docs or fix an issue, you’re going to need the
Salt repo. The best way to contribute is using
`Git <https://git-scm.com/>`__.

Environment Setup
-----------------

To hack on Salt or the docs you’re going to need to set up your
development environment. If you already have a workflow that you’re
comfortable with, you can use that, but otherwise this is an opinionated
guide for setting up your dev environment. Follow these steps and you’ll
end out with a functioning dev environment and be able to submit your
first PR.

This guide assumes at least a passing familiarity with
`Git <https://git-scm.com/>`__, a common version control tool used
across many open source projects, and is necessary for contributing to
Salt. For an introduction to Git, watch `Salt Docs Clinic - Git For the
True
Beginner <https://www.youtube.com/watch?v=zJw6KNvmuq4&ab_channel=SaltStack>`__.
Because of its widespread use, there are many resources for learning
more about Git. One popular resource is the free online book `Learn Git
in a Month of
Lunches <https://www.manning.com/books/learn-git-in-a-month-of-lunches>`__.

pyenv, Virtual Environments, and You
----------------------------------------

We recommend `pyenv <https://github.com/pyenv/pyenv>`__, since it allows
installing multiple different Python versions, which is important for
testing Salt across all the versions of Python that we support.

On Linux
~~~~~~~~

Install pyenv:

::

   git clone https://github.com/pyenv/pyenv.git ~/.pyenv
   export PATH="$HOME/.pyenv/bin:$PATH"
   git clone https://github.com/pyenv/pyenv-virtualenv.git $(pyenv root)/plugins/pyenv-virtualenv

On Mac
~~~~~~

Install pyenv using brew:

::

   brew update
   brew install pyenv
   brew install pyenv-virtualenv

--------------

Now add pyenv to your ``.bashrc``:

::

   echo 'export PATH="$HOME/.pyenv/bin:$PATH"' >> ~/.bashrc
   pyenv init 2>> ~/.bashrc
   pyenv virtualenv-init 2>> ~/.bashrc

For other shells, see `the pyenv
instructions <https://github.com/pyenv/pyenv#basic-github-checkout>`__.

Go ahead and restart your shell. Now you should be able to install a new
version of Python:

::

   pyenv install 3.7.0

If that fails, don’t panic! You’re probably just missing some build
dependencies. Check out `pyenv common build
problems <https://github.com/pyenv/pyenv/wiki/Common-build-problems>`__.

Now that you’ve got your version of Python installed, you can create a
new virtual environment with this command:

::

   pyenv virtualenv 3.7.0 salt

Then activate it:

::

   pyenv activate salt

Sweet! Now you’re ready to clone Salt so you can start hacking away! If
you get stuck at any point, check out the resources at the beginning of
this guide. IRC and Slack are particularly helpful places to go.

Get The Source!
~~~~~~~~~~~~~~~

Salt uses the fork and clone workflow for Git contributions. See `Using
the Fork-and-Branch Git
Workflow <https://blog.scottlowe.org/2015/01/27/using-fork-branch-git-workflow/>`__
for how to implement it. But if you just want to hurry and get started
you can go ahead and follow these steps:

Clones are so shallow. Well, this one is anyway:

::

   git clone --depth=1 --origin salt https://github.com/saltstack/salt.git

This creates a shallow clone of Salt, which should be fast. Most of the
time that’s all you’ll need, and you can start building out other
commits as you go. If you *really* want all 108,300+ commits you can
just run ``git fetch --unshallow``. Then go make a sandwich because it’s
gonna be a while.

You’re also going to want to head over to GitHub and create your own
`fork of Salt <https://github.com/saltstack/salt/fork>`__. Once you’ve
got that set up you can add it as a remote:

::

   git remote add yourname <YOUR SALT REMOTE>

If you use your name to refer to your fork, and ``salt`` to refer to the
official Salt repo you’ll never get ``upstream`` or ``origin`` confused.

.. note::

   Each time you start work on a new issue you should fetch the most recent
   changes from ``salt/upstream``.

``pre-commit`` and ``nox`` Setup
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Here at Salt we use `pre-commit <https://pre-commit.com/>`__ and
`nox <https://nox.thea.codes/en/stable/>`__ to make it easier for
contributors to get quick feedback, for quality control, and to increase
the chance that your merge request will get reviewed and merged. Nox
enables us to run multiple different test configurations, as well as
other common tasks. You can think of it as Make with superpowers.
Pre-commit does what it sounds like: it configures some Git pre-commit
hooks to run ``black`` for formatting, ``isort`` for keeping our imports
sorted, and ``pylint`` to catch issues like unused imports, among
others. You can easily install them in your virtualenv with:

::

   python -m pip install pre-commit nox
   pre-commit install

.. warning::
    Currently there is an issue with the pip-tools-compile pre-commit hook on Windows.
    The details around this issue are included here:
    https://github.com/saltstack/salt/issues/56642.
    Please ensure you export ``SKIP=pip-tools-compile`` to skip pip-tools-compile.

Now before each commit, it will ensure that your code at least *looks*
right before you open a pull request. And with that step, it’s time to
start hacking on Salt!

Salt Issues
-----------

Create Your Own
~~~~~~~~~~~~~~~

Perhaps you’ve come to this guide because you found a problem in Salt,
and you’ve diagnosed the cause. Maybe you need some help figuring out
the problem. In any case, creating quality bug reports is a great way to
contribute to Salt even if you lack the skills, time, or inclination to
fix it yourself. If that’s the case, head on over to `Salt’s issue
tracker on
GitHub <https://github.com/saltstack/salt/issues/new/choose>`__.

Creating a **good** report can take a little bit of time - but every
minute you invest in making it easier for others to reproduce and
understand your issue is time well spent. The faster someone can
understand your issue, the faster it will be able to get fixed
correctly.

The thing that every issue needs goes by many names, but one at least as
good as any other is MCVE - **M**\ inimum **C**\ omplete
**V**\ erifiable **E**\ xample.

In a nutshell:

-  **Minimum**: All of the **extra** information has been removed. Will
   2 or 3 lines of master/minion config still exhibit the behavior?
-  **Complete**: Minimum also means complete. If your example is missing
   information, then it’s not complete. Salt, Python, and OS versions
   are all bits of information that make your example complete. Have you
   provided the commands that you ran?
-  **Verifiable**: Can someone take your report and reproduce it?

Slow is smooth, and smooth is fast - it may feel like you’re taking a
long time to create your issue if you’re creating a proper MCVE, but a
MCVE eliminates back and forth required to reproduce/verify the issue so
someone can actually create a fix.

Pick An Issue
~~~~~~~~~~~~~

If you don’t already have an issue in mind, you can search for `help
wanted <https://github.com/saltstack/salt/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22>`__
issues. If you also search for `good first
issue <https://github.com/saltstack/salt/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22+label%3A%22good+first+issue%22>`__
then you should be able to find some issues that are good for getting
started contributing to Salt. `Documentation
issues <https://github.com/saltstack/salt/issues?q=is%3Aissue+is%3Aopen+label%3Adocumentation+>`__
are also good starter issues. When you find an issue that catches your
eye (or one of your own), it’s a good idea to comment on the issue and
mention that you’re working on it. Good communication is key to
collaboration - so if you don’t have time to complete work on the issue,
just leaving some information about when you expect to pick things up
again is a great idea!

Hacking Away
------------

Salt, Tests, Documentation, and You
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Before approving code contributions, Salt requires:

-  documentation
-  meaningful passing tests
-  correct code

Documentation fixes just require correct documentation.

What If I Don’t Write Tests or Docs?
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

If you aren’t into writing documentation or tests, we still welcome your
contributions! But your PR will be labeled ``Needs Testcase`` and
``Help Wanted`` until someone can get to write the tests/documentation.
Of course, if you have a desire but just lack the skill we are more than
happy to collaborate and help out! There’s the `documentation working
group <https://github.com/saltstack/docs-hub>`__ and the `testing
working
group <https://github.com/saltstack/community/tree/master/working_groups/wg-Testing>`__.
We also regularly stream our test clinic `live on
Twitch <https://www.twitch.tv/saltprojectoss>`__ every Tuesday afternoon
and Thursday morning, Central Time. If you’d like specific help with
tests, bring them to the clinic. If no community members need help, you
can also just watch tests written in real time.

.. _docs-building:

Documentation
~~~~~~~~~~~~~

Salt uses both docstrings, as well as normal reStructuredText files in
the ``salt/doc`` folder for documentation. Since we use nox, you can
build your docs and view them in your browser with this one-liner:

::

   python -m nox -e 'docs-html(compress=False, clean=False)'; cd doc/_build/html; python -m webbrowser http://localhost:8000/contents.html; python -m http.server

The first time this will take a while because there are a *lot* of
modules. Maybe you should go grab some dessert if you already finished
that sandwich. But once Sphinx is done building the docs, python should
launch your default browser with the URL
http://localhost:8000/contents.html. Now you can navigate to your docs
and ensure your changes exist. If you make changes, you can simply run
this:

::

   cd -; python -m nox -e 'docs-html(compress=False, clean=False)'; cd doc/_build/html; python -m http.server

And then refresh your browser to get your updated docs. This one should
be quite a bit faster since Sphinx won’t need to rebuild everything.

If your change is a docs-only change, you can go ahead and commit/push
your code and open a PR. You can indicate that it’s a docs-only change by
adding ``[Documentation]`` to the title of your PR. Otherwise you’ll
want to write some tests and code.

Running Development Salt
~~~~~~~~~~~~~~~~~~~~~~~~

Note: If you run into any issues in this section, check the
Troubleshooting section.

If you’re going to hack on the Salt codebase you’re going to want to be
able to run Salt locally. The first thing you need to do is install Salt
as an editable pip install:

::

   python -m pip install -e .

This will let you make changes to Salt without having to re-install it.

After all of the dependencies and Salt are installed, it’s time to set
up the config for development. Typically Salt runs as ``root``, but you
can specify which user to run as. To configure that, just copy the
master and minion configs. We have .gitignore setup to ignore the
``local/`` directory, so we can put all of our personal files there.

::

   mkdir -p local/etc/salt/

Create a master config file as ``local/etc/salt/master``:

::

   cat <<EOF >local/etc/salt/master
   user: $(whoami)
   root_dir: $PWD/local/
   publish_port: 55505
   ret_port: 55506
   EOF

And a minion config as ``local/etc/salt/minion``:

::

   cat <<EOF >local/etc/salt/minion
   user: $(whoami)
   root_dir: $PWD/local/
   master: localhost
   id: saltdev
   master_port: 55506
   EOF

Now you can start your Salt master and minion, specifying the config
dir.

::

   salt-master --config-dir=local/etc/salt/ --log-level=debug --daemon
   salt-minion --config-dir=local/etc/salt/ --log-level=debug --daemon

Now you should be able to accept the minion key:

::

   salt-key -c local/etc/salt -Ay

And check that your master/minion are communicating:

::

   salt -c local/etc/salt \* test.version

Rather than running ``test.version`` from your master, you can run it
from the minion instead:

::

   salt-call -c local/etc/salt test.version

Note that you’re running ``salt-call`` instead of ``salt``, and you’re
not specifying the minion (``\*``), but if you’re running the dev
version then you still will need to pass in the config dir. Now that
you’ve got Salt running, you can hack away on the Salt codebase!

If you need to restart Salt for some reason, if you’ve made changes and
they don’t appear to be reflected, this is one option:

::

   kill -INT $(pgrep salt-master)
   kill -INT $(pgrep salt-minion)

If you’d rather not use ``kill``, you can have a couple of terminals
open with your salt virtualenv activated and omit the ``--daemon``
argument. Salt will run in the foreground, so you can just use ctrl+c to
quit.

Test First? Test Last? Test Meaningfully!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You can write tests first or tests last, as long as your tests are
meaningful and complete! *Typically* the best tests for Salt are going
to be unit tests. Testing is `a whole topic on its
own <https://docs.saltproject.io/en/master/topics/tutorials/writing_tests.html>`__,
But you may also want to write functional or integration tests. You’ll
find those in the ``salt/tests`` directory.

When you’re thinking about tests to write, the most important thing to
keep in mind is, “What, exactly, am I testing?” When a test fails, you
should know:

-  What, specifically, failed?
-  Why did it fail?
-  As much as possible, what do I need to do to fix this failure?

If you can’t answer those questions then you might need to refactor your
tests.

When you’re running tests locally, you should make sure that if you
remove your code changes your tests are failing. If your tests *aren’t*
failing when you haven’t yet made changes, then it’s possible that
you’re testing the wrong thing.

But whether you adhere to TDD/BDD, or you write your code first and your
tests last, ensure that your tests are meaningful.

Running Tests
^^^^^^^^^^^^^

As previously mentioned, we use ``nox``, and that’s how we run our
tests. You should have it installed by this point but if not you can
install it with this:

::

   python -m pip install nox

Now you can run your tests:

::

   python -m nox -e "pytest-3.7(coverage=False)" -- tests/unit/cli/test_batch.py

It’s a good idea to install
`espeak <https://github.com/espeak-ng/espeak-ng>`__ or use ``say`` on
Mac if you’re running some long-running tests. You can do something like
this:

::

   python -m nox -e "pytest-3.7(coverage=False)" -- tests/unit/cli/test_batch.py; espeak "Tests done, woohoo!"

That way you don’t have to keep monitoring the actual test run.

Changelog and Commit!
~~~~~~~~~~~~~~~~~~~~~

When you write your commit message you should use imperative style. Do
this:

   Add frobnosticate capability

Don’t do this:

   Added frobnosticate capability

But that advice is backwards for the changelog. We follow the
`keepachangelog <https://keepachangelog.com/en/1.0.0/>`__ approach for
our changelog, and use towncrier to generate it for each release. As a
contributor, all that means is that you need to add a file to the
``salt/changelog`` directory, using the ``<issue #>.<type>`` format. For
instanch, if you fixed issue 123, you would do:

::

   echo "Made sys.doc inform when no minions return" > changelog/123.fixed

And that’s all that would go into your file. When it comes to your
commit message, it’s usually a good idea to add other information, such as

- What does a reviewer need to know about the change that you made?
- If someone isn’t an expert in this area, what will they need to know?

This will also help you out, because when you go to create the PR it
will automatically insert the body of your commit messages.

PR Time!
--------

Once you’ve done all your dev work and tested locally, you should check
out our `PR
guidelines <https://docs.saltproject.io/en/master/topics/development/pull_requests.html>`__.
After you read that page, it’s time to `open a new
PR <https://github.com/saltstack/salt/compare>`__. Fill out the PR
template - you should have updated or created any necessary docs, and
written tests if you’re providing a code change. When you submit your
PR, we have a suite of tests that will run across different platforms to
help ensure that no known bugs were introduced.

Now What?
~~~~~~~~~

You’ve made your changes, added documentation, opened your PR, and have
passing tests… now what? When can you expect your code to be merged?

When you open your PR, a reviewer will get automatically assigned. If
your PR is submitted during the week you should be able to expect some
kind of communication within that business day. If your tests are
passing and we’re not in a code freeze, ideally your code will be merged
that day. If you haven’t heard from your assigned reviewer, ping them on
GitHub, `irc <https://webchat.freenode.net/#salt>`__, or Community
Slack.

It’s likely that your reviewer will leave some comments that need
addressing - it may be a style change, or you forgot a changelog entry,
or need to update the docs. Maybe it’s something more fundamental -
perhaps you encountered the rare case where your PR has a much larger
scope than initially assumed.

Whatever the case, simply make the requested changes (or discuss why the
requests are incorrect), and push up your new commits. If your PR is
open for a significant period of time it may be worth rebasing your
changes on the most recent changes to Salt. If you need help, the
previously linked Git resources will be valuable.

But if, for whatever reason, you’re not interested in driving your PR to
completion then just note that in your PR. Something like, “I’m not
interested in writing docs/tests, I just wanted to provide this fix -
someone else will need to complete this PR.” If you do that then we’ll
add a “Help Wanted” label and someone will be able to pick up the PR,
make the required changes, and it can eventually get merged in.

In any case, now that you have a PR open, congrats! You’re a Salt
developer! You rock!

Troubleshooting
---------------

zmq.core.error.ZMQError
~~~~~~~~~~~~~~~~~~~~~~~

Once the minion starts, you may see an error like the following::

::

   zmq.core.error.ZMQError: ipc path "/path/to/your/virtualenv/var/run/salt/minion/minion_event_7824dcbcfd7a8f6755939af70b96249f_pub.ipc" is longer than 107 characters (sizeof(sockaddr_un.sun_path)).

This means that the path to the socket the minion is using is too long.
This is a system limitation, so the only workaround is to reduce the
length of this path. This can be done in a couple different ways:

1. Create your virtualenv in a path that is short enough.
2. Edit the :conf_minion:``sock_dir`` minion config variable and reduce
   its length. Remember that this path is relative to the value you set
   in :conf_minion:``root_dir``.

NOTE: The socket path is limited to 107 characters on Solaris and Linux,
and 103 characters on BSD-based systems.

No permissions to access …
~~~~~~~~~~~~~~~~~~~~~~~~~~

If you forget to pass your config path to any of the ``salt*`` commands,
you might see

::

   No permissions to access "/var/log/salt/master", are you running as the
   correct user?

Just pass ``-c local/etc/salt`` (or whatever you named it)

File descriptor limit
~~~~~~~~~~~~~~~~~~~~~

You might need to raise your file descriptor limit. You can check it
with:

::

   ulimit -n

If the value is less than 3072, you should increase it with:

::

   ulimit -n 3072
   # For c-shell:
   limit descriptors 3072

Pygit2 or other dependency install fails
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You may see some failure messages when installing requirements. You can
directly access your nox environment and possibly install pygit (or
other dependency) that way. When you run nox, you’ll see a message like
this:

::

   nox > Re-using existing virtual environment at .nox/pytest-parametrized-3-crypto-none-transport-zeromq-coverage-false.

For this, you would be able to install with:

::

   .nox/pytest-parametrized-3-crypto-none-transport-zeromq-coverage-false/bin/python -m pip install pygit2