=====================

Writing documentation

=====================

We place high importance on the consistency and readability of documentation.

After all, Django was created in a journalism environment! So we treat our

documentation like we treat our code: we aim to improve it as often as

possible.

Documentation changes generally come in two forms:

* General improvements: typo corrections, error fixes and better

  explanations through clearer writing and more examples.

* New features: documentation of features that have been added to the

  framework since the last release.

This section explains how writers can craft their documentation changes

in the most useful and least error-prone ways.

Getting the raw documentation

=============================

Though Django's documentation is intended to be read as HTML at

https://docs.djangoproject.com/, we edit it as a collection of text files for

maximum flexibility. These files live in the top-level ``docs/`` directory of a

Django release.

If you'd like to start contributing to our docs, get the development version of

Django from the source code repository

(see :ref:`installing-development-version`). The development version has the

latest-and-greatest documentation, just as it has the latest-and-greatest code.

We also backport documentation fixes and improvements, at the discretion of the

merger, to the last release branch. That's because it's highly advantageous to

have the docs for the last release be up-to-date and correct (see

:ref:`differences-between-doc-versions`).

Getting started with Sphinx

===========================

Django's documentation uses the Sphinx__ documentation system, which in turn

is based on docutils__. The basic idea is that lightly-formatted plain-text

documentation is transformed into HTML, PDF, and any other output format.

__ https://www.sphinx-doc.org/

__ https://docutils.sourceforge.io/

To build the documentation locally, install Sphinx:

.. console::

     $ python -m pip install Sphinx

Then from the ``docs`` directory, build the HTML:

.. console::

     $ make html

To get started contributing, you'll want to read the :ref:`reStructuredText

reference <sphinx:rst-index>`.

Your locally-built documentation will be themed differently than the

documentation at `docs.djangoproject.com <https://docs.djangoproject.com/>`_.

This is OK! If your changes look good on your local machine, they'll look good

on the website.

How the documentation is organized

==================================

The documentation is organized into several categories:

* :doc:`Tutorials </intro/index>` take the reader by the hand through a series

  of steps to create something.

  The important thing in a tutorial is to help the reader achieve something

  useful, preferably as early as possible, in order to give them confidence.

  Explain the nature of the problem we're solving, so that the reader

  understands what we're trying to achieve. Don't feel that you need to begin

  with explanations of how things work - what matters is what the reader does,

  not what you explain. It can be helpful to refer back to what you've done and

  explain afterward.

* :doc:`Topic guides </topics/index>` aim to explain a concept or subject at a

  fairly high level.

  Link to reference material rather than repeat it. Use examples and don't be

  reluctant to explain things that seem very basic to you - it might be the

  explanation someone else needs.

  Providing background context helps a newcomer connect the topic to things

  that they already know.

* :doc:`Reference guides </ref/index>` contain technical references for APIs.

  They describe the functioning of Django's internal machinery and instruct in

  its use.

  Keep reference material tightly focused on the subject. Assume that the

  reader already understands the basic concepts involved but needs to know or

  be reminded of how Django does it.

  Reference guides aren't the place for general explanation. If you find

  yourself explaining basic concepts, you may want to move that material to a

  topic guide.

* :doc:`How-to guides </howto/index>` are recipes that take the reader through

  steps in key subjects.

  What matters most in a how-to guide is what a user wants to achieve.

  A how-to should always be result-oriented rather than focused on internal

  details of how Django implements whatever is being discussed.

  These guides are more advanced than tutorials and assume some knowledge about

  how Django works. Assume that the reader has followed the tutorials and don't

  hesitate to refer the reader back to the appropriate tutorial rather than

  repeat the same material.

Writing style

=============

When using pronouns in reference to a hypothetical person, such as "a user with

a session cookie", gender-neutral pronouns (they/their/them) should be used.

Instead of:

* he or she... use they.

* him or her... use them.

* his or her... use their.

* his or hers... use theirs.

* himself or herself... use themselves.

Try to avoid using words that minimize the difficulty involved in a task or

operation, such as "easily", "simply", "just", "merely", "straightforward", and

so on. People's experience may not match your expectations, and they may become

frustrated when they do not find a step as "straightforward" or "simple" as it

is implied to be.

Commonly used terms

===================

Here are some style guidelines on commonly used terms throughout the

documentation:

* **Django** -- when referring to the framework, capitalize Django. It is

  lowercase only in Python code and in the djangoproject.com logo.

* **email** -- no hyphen.

* **HTTP** -- the expected pronunciation is "Aitch Tee Tee Pee" and therefore

  should be preceded by "an" and not "a".

* **MySQL**, **PostgreSQL**, **SQLite**

* **SQL** -- when referring to SQL, the expected pronunciation should be

  "Ess Queue Ell" and not "sequel". Thus in a phrase like "Returns an

  SQL expression", "SQL" should be preceded by "an" and not "a".

* **Python** -- when referring to the language, capitalize Python.

* **realize**, **customize**, **initialize**, etc. -- use the American

  "ize" suffix, not "ise."

* **subclass** -- it's a single word without a hyphen, both as a verb

  ("subclass that model") and as a noun ("create a subclass").

* **the web**, **web framework** -- it's not capitalized.

* **website** -- use one word, without capitalization.

Django-specific terminology

===========================

* **model** -- it's not capitalized.

* **template** -- it's not capitalized.

* **URLconf** -- use three capitalized letters, with no space before

  "conf."

* **view** -- it's not capitalized.

Guidelines for reStructuredText files

=====================================

These guidelines regulate the format of our reST (reStructuredText)

documentation:

* In section titles, capitalize only initial words and proper nouns.

* Wrap the documentation at 80 characters wide, unless a code example

  is significantly less readable when split over two lines, or for another

  good reason.

* The main thing to keep in mind as you write and edit docs is that the

  more semantic markup you can add the better. So::

      Add ``django.contrib.auth`` to your ``INSTALLED_APPS``...

  Isn't nearly as helpful as::

      Add :mod:`django.contrib.auth` to your :setting:`INSTALLED_APPS`...

  This is because Sphinx will generate proper links for the latter, which

  greatly helps readers.

  You can prefix the target with a ``~`` (that's a tilde) to get only the

  "last bit" of that path. So ``:mod:`~django.contrib.auth``` will

  display a link with the title "auth".

* Use :mod:`~sphinx.ext.intersphinx` to reference Python's and Sphinx'

  documentation.

* Add ``.. code-block:: <lang>`` to literal blocks so that they get

  highlighted. Prefer relying on automatic highlighting using ``::``

  (two colons). This has the benefit that if the code contains some invalid

  syntax, it won't be highlighted. Adding ``.. code-block:: python``, for

  example, will force highlighting despite invalid syntax.

* To improve readability, use ``.. admonition:: Descriptive title`` rather than

  ``.. note::``. Use these boxes sparingly.

* Use these heading styles::

    ===

    One

    ===

    Two

    ===

    Three

    -----

    Four

    ~~~~

    Five

    ^^^^

* Use :rst:role:`:rfc:<rfc>` to reference RFC and try to link to the relevant

  section if possible. For example, use ``:rfc:`2324#section-2.3.2``` or

  ``:rfc:`Custom link text <2324#section-2.3.2>```.

* Use :rst:role:`:pep:<pep>` to reference a Python Enhancement Proposal (PEP)

  and try to link to the relevant section if possible. For example, use

  ``:pep:`20#easter-egg``` or ``:pep:`Easter Egg <20#easter-egg>```.

* Use :rst:role:`:mimetype:<mimetype>` to refer to a MIME Type unless the value

  is quoted for a code example.

* Use :rst:role:`:envvar:<envvar>` to refer to an environment variable. You may

  also need to define a reference to the documentation for that environment

  variable using :rst:dir:`.. envvar:: <envvar>`.

Django-specific markup

======================

Besides :ref:`Sphinx's built-in markup <sphinx:rst-index>`, Django's docs

define some extra description units:

* Settings::

        .. setting:: INSTALLED_APPS

  To link to a setting, use ``:setting:`INSTALLED_APPS```.

* Template tags::

        .. templatetag:: regroup

  To link, use ``:ttag:`regroup```.

* Template filters::

        .. templatefilter:: linebreaksbr

  To link, use ``:tfilter:`linebreaksbr```.

* Field lookups (i.e. ``Foo.objects.filter(bar__exact=whatever)``)::

        .. fieldlookup:: exact

  To link, use ``:lookup:`exact```.

* ``django-admin`` commands::

        .. django-admin:: migrate

  To link, use ``:djadmin:`migrate```.

* ``django-admin`` command-line options::

        .. django-admin-option:: --traceback

  To link, use ``:option:`command_name --traceback``` (or omit ``command_name``

  for the options shared by all commands like ``--verbosity``).

* Links to Trac tickets (typically reserved for patch release notes)::

        :ticket:`12345`

Django's documentation uses a custom ``console`` directive for documenting

command-line examples involving ``django-admin``, ``manage.py``, ``python``,

etc.). In the HTML documentation, it renders a two-tab UI, with one tab showing

a Unix-style command prompt and a second tab showing a Windows prompt.

For example, you can replace this fragment::

    use this command:

    .. code-block:: console

        $ python manage.py shell

with this one::

    use this command:

    .. console::

        $ python manage.py shell

Notice two things:

* You usually will replace occurrences of the ``.. code-block:: console``

  directive.

* You don't need to change the actual content of the code example. You still

  write it assuming a Unix-y environment (i.e. a ``'$'`` prompt symbol,

  ``'/'`` as filesystem path components separator, etc.)

The example above will render a code example block with two tabs. The first

one will show:

.. code-block:: console

    $ python manage.py shell

(No changes from what ``.. code-block:: console`` would have rendered).

The second one will show:

.. code-block:: doscon

    ...\> py manage.py shell

.. _documenting-new-features:

Documenting new features

========================

Our policy for new features is:

    All documentation of new features should be written in a way that

    clearly designates the features that are only available in the Django

    development version. Assume documentation readers are using the latest

    release, not the development version.

Our preferred way for marking new features is by prefacing the features'

documentation with: "``.. versionadded:: X.Y``", followed by a mandatory

blank line and an optional description (indented).

General improvements or other changes to the APIs that should be emphasized

should use the "``.. versionchanged:: X.Y``" directive (with the same format

as the ``versionadded`` mentioned above.

These ``versionadded`` and ``versionchanged`` blocks should be "self-contained."

In other words, since we only keep these annotations around for two releases,

it's nice to be able to remove the annotation and its contents without having

to reflow, reindent, or edit the surrounding text. For example, instead of

putting the entire description of a new or changed feature in a block, do

something like this::

    .. class:: Author(first_name, last_name, middle_name=None)

        A person who writes books.

        ``first_name`` is ...

        ...

        ``middle_name`` is ...

        .. versionchanged:: A.B

            The ``middle_name`` argument was added.

Put the changed annotation notes at the bottom of a section, not the top.

Also, avoid referring to a specific version of Django outside a

``versionadded`` or ``versionchanged`` block. Even inside a block, it's often

redundant to do so as these annotations render as "New in Django A.B:" and

"Changed in Django A.B", respectively.

If a function, attribute, etc. is added, it's also okay to use a

``versionadded`` annotation like this::

    .. attribute:: Author.middle_name

        .. versionadded:: A.B

        An author's middle name.

We can remove the ``.. versionadded:: A.B`` annotation without any indentation

changes when the time comes.

Minimizing images

=================

Optimize image compression where possible. For PNG files, use OptiPNG and

AdvanceCOMP's ``advpng``:

.. code-block:: console

   $ cd docs

   $ optipng -o7 -zm1-9 -i0 -strip all `find . -type f -not -path "./_build/*" -name "*.png"`

   $ advpng -z4 `find . -type f -not -path "./_build/*" -name "*.png"`

This is based on OptiPNG version 0.7.5. Older versions may complain about the

``-strip all`` option being lossy.

An example

==========

For a quick example of how it all fits together, consider this hypothetical

example:

* First, the ``ref/settings.txt`` document could have an overall layout

  like this:

  .. code-block:: rst

    ========

    Settings

    ========

    ...

    .. _available-settings:

    Available settings

    ==================

    ...

    .. _deprecated-settings:

    Deprecated settings

    ===================

    ...

* Next, the ``topics/settings.txt`` document could contain something like

  this:

  .. code-block:: rst

    You can access a :ref:`listing of all available settings

    <available-settings>`. For a list of deprecated settings see

    :ref:`deprecated-settings`.

    You can find both in the :doc:`settings reference document

    </ref/settings>`.

  We use the Sphinx :rst:role:`doc` cross-reference element when we want to

  link to another document as a whole and the :rst:role:`ref` element when

  we want to link to an arbitrary location in a document.

* Next, notice how the settings are annotated:

  .. code-block:: rst

    .. setting:: ADMINS

    ADMINS

    ======

    Default: ``[]`` (Empty list)

    A list of all the people who get code error notifications. When

    ``DEBUG=False`` and a view raises an exception, Django will email these people

    with the full exception information. Each member of the list should be a tuple

    of (Full name, email address). Example::

        [('John', '[email protected]'), ('Mary', '[email protected]')]

    Note that Django will email *all* of these people whenever an error happens.

    See :doc:`/howto/error-reporting` for more information.

  This marks up the following header as the "canonical" target for the

  setting ``ADMINS``. This means any time I talk about ``ADMINS``,

  I can reference it using ``:setting:`ADMINS```.

That's basically how everything fits together.

.. _documentation-spelling-check:

Spelling check

==============

Before you commit your docs, it's a good idea to run the spelling checker.

You'll need to install `sphinxcontrib-spelling

<https://pypi.org/project/sphinxcontrib-spelling/>`_ first. Then from the

``docs`` directory, run ``make spelling``. Wrong words (if any) along with the

file and line number where they occur will be saved to

``_build/spelling/output.txt``.

If you encounter false-positives (error output that actually is correct), do

one of the following:

* Surround inline code or brand/technology names with grave accents (`).

* Find synonyms that the spell checker recognizes.

* If, and only if, you are sure the word you are using is correct - add it

  to ``docs/spelling_wordlist`` (please keep the list in alphabetical order).

.. _documentation-link-check:

Link check

==========

Links in documentation can become broken or changed such that they are no

longer the canonical link. Sphinx provides a builder that can check whether the

links in the documentation are working. From the ``docs`` directory, run ``make

linkcheck``. Output is printed to the terminal, but can also be found in

``_build/linkcheck/output.txt`` and ``_build/linkcheck/output.json``.

Entries that have a status of "working" are fine, those that are "unchecked" or

"ignored" have been skipped because they either cannot be checked or have

matched ignore rules in the configuration.

Entries that have a status of "broken" need to be fixed. Those that have a

status of "redirected" may need to be updated to point to the canonical

location, e.g. the scheme has changed ``http://`` → ``https://``. In certain

cases, we do not want to update a "redirected" link, e.g. a rewrite to always

point to the latest or stable version of the documentation, e.g. ``/en/stable/`` →

``/en/3.2/``.

Translating documentation

=========================

See :ref:`Localizing the Django documentation <translating-documentation>` if

you'd like to help translate the documentation into another language.

.. _django-admin-manpage:

``django-admin`` man page

=========================

Sphinx can generate a manual page for the

:doc:`django-admin </ref/django-admin>` command. This is configured in

``docs/conf.py``. Unlike other documentation output, this man page should be

included in the Django repository and the releases as

``docs/man/django-admin.1``. There isn't a need to update this file when

updating the documentation, as it's updated once as part of the release process.

To generate an updated version of the man page, run ``make man`` in the

``docs`` directory. The new man page will be written in

``docs/_build/man/django-admin.1``.