Internationalization

New in version 1.1.

Complementary to translations provided for Sphinx-generated messages such as navigation bars, Sphinx provides mechanisms facilitating the translation of documents. See the Options for internationalization for details on configuration.

Workflow visualization of translations in Sphinx. (The figure is created by plantuml.)¶

gettext [1] is an established standard for internationalization and localization. It naively maps messages in a program to a translated string. Sphinx uses these facilities to translate whole documents.

Initially project maintainers have to collect all translatable strings (also referred to as messages) to make them known to translators. Sphinx extracts these through invocation of sphinx-build -b gettext.

Every single element in the doctree will end up in a single message which results in lists being equally split into different chunks while large paragraphs will remain as coarsely-grained as they were in the original document. This grants seamless document updates while still providing a little bit of context for translators in free-text passages. It is the maintainer’s task to split up paragraphs which are too large as there is no sane automated way to do that.

After Sphinx successfully ran the MessageCatalogBuilder you will find a collection of .pot files in your output directory. These are catalog templates and contain messages in your original language only.

They can be delivered to translators which will transform them to .po files — so called message catalogs — containing a mapping from the original messages to foreign-language strings.

gettext compiles them into a binary format known as binary catalogs through msgfmt for efficiency reasons. If you make these files discoverable with locale_dirs for your language, Sphinx will pick them up automatically.

An example: you have a document usage.rst in your Sphinx project. The gettext builder will put its messages into usage.pot. Imagine you have Spanish translations [2] stored in usage.po — for your builds to be translated you need to follow these instructions:

Compile your message catalog to a locale directory, say locale, so it ends up in ./locale/es/LC_MESSAGES/usage.mo in your source directory (where es is the language code for Spanish.)

Set locale_dirs to ["locale/"].

Set language to es (also possible via -D).

Run your desired build.

In order to protect against mistakes, a warning is emitted if cross-references in the translated paragraph do not match those from the original. This can be turned off globally using the suppress_warnings configuration variable. Alternatively, to turn it off for one message only, end the message with #noqa like this:

(Write \#noqa in case you want to have “#noqa” literally in the text. This does not apply to code blocks, where #noqa is ignored because code blocks do not contain references anyway.)

New in version 4.5: The #noqa mechanism.

sphinx-intl is a useful tool to work with Sphinx translation flow. This section describe an easy way to translate with sphinx-intl.

Install sphinx-intl.

Add configurations to conf.py.

This case-study assumes that BUILDDIR is set to _build, locale_dirs is set to locale/ and gettext_compact is set to False (the Sphinx document is already configured as such).

Extract translatable messages into pot files.

The generated pot files will be placed in the _build/gettext directory.

Generate po files.

We’ll use the pot files generated in the above step.

Once completed, the generated po files will be placed in the below directories:

./locale/de/LC_MESSAGES/

./locale/ja/LC_MESSAGES/

Translate po files.

As noted above, these are located in the ./locale//LC_MESSAGES directory. An example of one such file, from Sphinx, builders.po, is given below.

Another case, msgid is multi-line text and contains reStructuredText syntax:

Please be careful not to break reST notation. Most po-editors will help you with that.

Build translated document.

You need a language parameter in conf.py or you may also specify the parameter on the command line.

For BSD/GNU make, run:

For Windows cmd.exe, run:

For PowerShell, run:

Congratulations! You got the translated documentation in the _build/html directory.

New in version 1.3: sphinx-build that is invoked by make command will build po files into mo files.

If you are using 1.2.x or earlier, please invoke sphinx-intl build command before make command.

If a document is updated, it is necessary to generate updated pot files and to apply differences to translated po files. In order to apply the updates from a pot file to the po file, use the sphinx-intl update command.

Transifex is one of several services that allow collaborative translation via a web interface. It has a nifty Python-based command line client that makes it easy to fetch and push translations.

Install transifex-client.

You need tx command to upload resources (pot files).

See also

Transifex Client documentation

Create your Transifex account and create new project for your document.

Currently, Transifex does not allow for a translation project to have more than one version of the document, so you’d better include a version number in your project name.

For example:

sphinx-document-test_1_0

https://www.transifex.com/projects/p/sphinx-document-test_1_0/

Create config files for tx command.

This process will create .tx/config in the current directory, as well as a ~/.transifexrc file that includes auth information.

Upload pot files to Transifex service.

Register pot files to .tx/config file:

and upload pot files:

Forward the translation on Transifex.

Pull translated po files and make translated HTML.

Get translated catalogs and build mo files. For example, to build mo files for German (de):

Invoke make html (for BSD/GNU make):

That’s all!

Tip

Translating locally and on Transifex

If you want to push all language’s po files, you can be done by using tx push -t command. Watch out! This operation overwrites translations in Transifex.

In other words, if you have updated each in the service and local po files, it would take much time and effort to integrate them.

Read more in Weblate’s documentation.

The recommended way for new contributors to translate Sphinx reference is to join the translation team on Transifex.

There is a sphinx translation page for Sphinx (master) documentation.

Login to Transifex service.

Go to sphinx translation page.

Click Request language and fill form.

Wait acceptance by Transifex sphinx translation maintainers.

(After acceptance) Translate on Transifex.

Detail is here: https://docs.transifex.com/getting-started-1/translators

New in version 7.1.0.

During the rendering process, Sphinx marks each translatable node with a translated attribute, indicating if a translation was found for the text in that node.

The translation_progress_classes configuration value can be used to add a class to each element, depending on the value of the translated attribute.

The |translation progress| substitution can be used to display the percentage of nodes that have been translated on a per-document basis.

Footnotes

See the GNU gettext utilities for details on that software suite.

Because nobody expects the Spanish Inquisition!