Translating tasks

INGInious provides support for translating tasks in the language of your student. Most users will want to use the feedback-msg-tpl command, which is the most straighforward way to do translation.

Another possible method is to use gettext. This is by default supported in Python script and feedback templates, but you can use gettext in any language.

Four steps are necessary to translate a task:

  • Mark strings as translatable
  • Extract strings to create a .po file
  • Translate the extracted strings
  • Compile the translated strings into a .mo file

Marking strings in Python scripts

Simply import inginious.lang and run the command inginious.lang.init(). This will install the function _() that can be used to mark strings as translatable.


Marking strings in feedback templates

The function _() in always available in feedback templates:

{{ _("Hello") }}

Extracting strings

Now you need to extract the strings, for this we use babel. If it’s not already done, install babel:

pip3 install babel

Create a file named “mapping.babel”, which contains the babel mapping <>. Here is an example of mapping that will extract both strings marked in Python and in feedback (Jinja2) templates:

[python: **.py]
[jinja2: **.tpl]
encoding = utf-8

If you use other languages, you may want to add the needed options in this file. Refer to the babel documentation.

Now, simply run the following command, which will creates a messages.pot file in your current directory:

pybabel extract -o messages.pot -F mapping.babel .

This messages.pot contains a very simple representation of the strings to translate. Here is an example of what you should obtain after running the command:

#: test.tpl:1
msgid "Hello"
msgstr ""

This will be the basis for all your translations. Let us put the file in the right place, by creating the correct directory structure:

pybabel init -i messages.pot -d lang -l fr_FR

Replace fr_FR by the language your are translating to. This will create a file lang/fr_FR/LC_MESSAGES/message.po.

Translating strings

In this file, simply change the msgstr entries with the translation of the immediately above msgid. For example, to translate the previous exemple
in french


#: test.tpl:1
msgid "Hello"
msgstr "Bonjour"

Compile your .po file into a .mo

The final step is to compile your text-based .po file into a binary .mo file, which ensures that translation occurs smoothly.

pybabel compile -d lang

Which will update all your translations.

I need more help with gettext

Gettext is a widely used tool; you will find a lot of software-independent help on the net :-)