编写文档

我们极其重视文档的一致性和可读性。毕竟,Django 是在需要快速发布新闻的环境下开发的!所以,我们像对待我们的代码一样对待我们的文档:我们期望尽可能频繁地更新它。

一般来说,文档会在以下两种情况时更新:

  • 一般改进:通过更清晰的书写和更多示例,更正、修复文档错误,更好的解释功能。
  • 新特性:自上一个版本发布后,添加到框架中的功能文档。

本节介绍文档作者如何以最有用和最不容易出错的方式修改文档。

获得原始文档

Django 文档可在 https://docs.djangoproject.com/ 以网页的形式阅读,但我们以一种更灵活的方式编辑它——一系列的文本文件。这些文件位于 Django 的每个发布分支的顶级目录 docs/ 下。

如果你想修改文档,请先从源码仓库获取开发版的 Django (参见 安装开发版)。开发版拥有最新最好的文档,就像它拥有最新最好的代码一样。我们也会在最新发布分支上提交针对文档的修复和优化(取决于提交者)。这是因为让最新版本的文档保持最新和正确是非常有利的(参见 不同版本文档间的区别)。

开始使用 Sphinx

Django 的文档使用 Sphinx 文档系统——基于 docutils。基本思想是将轻量格式话的纯文本转化为 HTML,PDF 或其它任意输出格式。

To build the documentation locally, install Sphinx:

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

Then from the docs directory, build the HTML:

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

编写文档前,你需要阅读 reStructuredText 指引

本地构建的文档的主题会和 docs.djangoproject.com 上的不同。没事!如果你修改后的文档在本地看起来没啥问题,那么在网站上也会没问题。

文档是如何组成

文档被分为以下几个类别:

  • 教程 通过几步手把手的教学帮助读者创建一个小玩意。

    教程的目的是帮助读者尽可能早地实现一些有用的东西,以便给他们带来信心。

    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 afterwards.

  • 主题指引 旨在在一个较高的层次介绍一个原则或主题。

    链接至参考资料而不要重复它。使用示例时,不要不情愿解释对您而言非常基本的事物——它对别人而言可能需要解释。

    提供背景信息有助于新人将主题和他们已知的东西联系起来。

  • Reference guides contain technical reference 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.

书写格式

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:

  • 他或她……使用他们。
  • him 或 her... 使用 them。
  • 他的或她的……使用他们的。
  • his 或 hers... 使用 theirs。
  • himself 或 herself... 使用 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.

常用术语

以下是整个文档中常用术语的一些格式指南:

  • Django -- 当提及该框架时,大写Django。它仅在Python代码中和djangoproject.com徽标中使用小写字母。
  • email -- 无连字符。
  • MySQL, PostgreSQL, SQLite
  • SQL -- 当提及SQL时,预期的发音应该是“Ess Queue Ell”而不是“sequel”。因此,在诸如“Returns an SQL expression”之类的短语中,“SQL”前应该使用“an”而不是“a”。
  • Python -- 当提及该语言时大写。
  • realize, customize, initialize, etc. -- 使用美式的“ize”后缀,而不是“ise”。
  • subclass -- 它是一个没有连字符的单个单词,既作为动词(“子类模型”)又作为名词(“创建子类”)。
  • Web, World Wide Web, the Web -- 指万维网时注意Web总是大写。
  • website -- 用一个单词表示,不大写。

Django专用术语

  • model (模型) -- 它不是大写的。
  • template -- 它不是大写的。
  • URLconf -- 使用了三个大写字母,在“conf”之前没有空格。
  • view -- 它不是大写的。

reStructuredText 文件语法指南

这些准则规定了我们的reST(reStructuredText)文档格式:

  • 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 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 :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>`.

Django-specific markup

Besides Sphinx's built-in markup, 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.py, 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:

$ python manage.py shell

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

The second one will show:

...\> 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 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:

$ 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.

一个例子

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:

    ========
    Settings
    ========
    
    ...
    
    .. _available-settings:
    
    Available settings
    ==================
    
    ...
    
    .. _deprecated-settings:
    
    Deprecated settings
    ===================
    
    ...
    
  • Next, the topics/settings.txt document could contain something like this:

    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 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:

    .. 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', 'john@example.com'), ('Mary', 'mary@example.com')]
    
    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.

拼写检查

在提交文档前运行拼写检查是个不错的注意。你需要先装几个包:

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 (`).
  • 查找拼写检查程序发现的同义词。
  • 如果,只是如果,你确定你的单词拼写是正确的——将其加入 docs/spelling_wordlist (请保持这个列表以字母顺序排列)。

翻译文档

查看 本地化 Django 文档,如果你想帮助我们将文档翻译成其它语言。

django-admin 手册页面

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.