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 Installing the 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 Differences between 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.

To build the documentation locally, install Sphinx:

/ 

  1. $ python -m pip install Sphinx
  1. ...\> py -m pip install Sphinx

Then from the docs directory, build the HTML:

/ 

  1. $ make html
  1. ...\> make.bat html

To get started contributing, you’ll want to read the reStructuredText reference.

Your locally-built documentation will be accessible at docs/_build/html/index.html and it can be viewed in any web browser, though it will be themed differently than the documentation at 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:

  • Tutorials 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.

  • Topic guides 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.

  • Reference guides 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.

  • How-to guides 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:

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

    Isn’t nearly as helpful as:

    1. 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”.

  • All Python code blocks should be formatted using the blacken-docs auto-formatter. This will be run by pre-commit if that is configured.

  • Use 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:

    1. ===
    2. One
    3. ===
    5. Two
    6. ===
    8. Three
    9. -----
    11. Four
    12. ~~~~
    14. Five
    15. ^^^^

  • Use :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 :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 :mimetype: to refer to a MIME Type unless the value is quoted for a code example.

  • Use :envvar: to refer to an environment variable. You may also need to define a reference to the documentation for that environment variable using .. envvar::.

Changed in Django 4.2:

All Python code blocks in the Django documentation were reformatted with blacken-docs.

Django-specific markup

Besides Sphinx’s built-in markup, Django’s docs define some extra description units:

  • Settings:

    1. .. setting:: INSTALLED_APPS

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

  • Template tags:

    1. .. templatetag:: regroup

    To link, use :ttag:`regroup` .

  • Template filters:

    1. .. templatefilter:: linebreaksbr

    To link, use :tfilter:`linebreaksbr` .

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

    1. .. fieldlookup:: exact

    To link, use :lookup:`exact` .

  • django-admin commands:

    1. .. django-admin:: migrate

    To link, use :djadmin:`migrate` .

  • django-admin command-line options:

    1. .. 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):

    1. :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:

  1. use this command:
  3. .. code-block:: console
  5.     $ python manage.py shell

with this one:

  1. use this command:
  3. .. console::
  5.     $ 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:

  1. $ python manage.py shell

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

The second one will show:

  1. ...\> py manage.py shell

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:

  1. .. class:: Author(first_name, last_name, middle_name=None)
  3.     A person who writes books.
  5.     ``first_name`` is ...
  7.     ...
  9.     ``middle_name`` is ...
  11.     .. versionchanged:: A.B
  13.         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:

  1. .. attribute:: Author.middle_name
  3.     .. versionadded:: A.B
  5.     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:

  1. $ cd docs
  2. $ optipng -o7 -zm1-9 -i0 -strip all `find . -type f -not -path "./_build/*" -name "*.png"`
  3. $ 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:

    1. ========
    2. Settings
    3. ========
    5. ...
    7. .. _available-settings:
    9. Available settings
    10. ==================
    12. ...
    14. .. _deprecated-settings:
    16. Deprecated settings
    17. ===================
    19. ...

  • Next, the topics/settings.txt document could contain something like this:

    1. You can access a :ref:`listing of all available settings
    2. <available-settings>`. For a list of deprecated settings see
    3. :ref:`deprecated-settings`.
    5. You can find both in the :doc:`settings reference document
    6. </ref/settings>`.

    We use the Sphinx doc cross-reference element when we want to link to another document as a whole and the ref element when we want to link to an arbitrary location in a document.

  • Next, notice how the settings are annotated:

    1. .. setting:: ADMINS
    3. ADMINS
    4. ======
    6. Default: ``[]`` (Empty list)
    8. A list of all the people who get code error notifications. When
    9. ``DEBUG=False`` and a view raises an exception, Django will email these people
    10. with the full exception information. Each member of the list should be a tuple
    11. of (Full name, email address). Example::
    13.     [("John", "john@example.com"), ("Mary", "mary@example.com")]
    15. Note that Django will email *all* of these people whenever an error happens.
    16. 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.

Spelling check

Before you commit your docs, it’s a good idea to run the spelling checker. You’ll need to install 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 double 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).

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 Localizing the Django documentation if you’d like to help translate the documentation into another language.

django-admin man page

Sphinx can generate a manual page for the 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.