Add some documentation about extraction

symfony/extracting-translations.rst

@@ -1,4 +1,38 @@
 Extracting Translations from Source
 ===================================
 
-TODO example how to extract source. Show different configurations and commands.
+Extracting translations from your project
+-----------------------------------------
+
+.. code-block:: yaml
+
+    translation:
+      locales: ["en", "fr", "sv"]
+      configs:
+        app:
+          dirs: ["%kernel.root_dir%/Resources/views", "%kernel.root_dir%/../src"]
+          output_dir: "%kernel.root_dir%/Resources/translations"
+          excluded_names: ["*TestCase.php", "*Test.php"]
+          excluded_dirs: [cache, data, logs]
+
+With the configuration above you may extract all translation keys from your
+source code by running
+
+.. code-block:: bash
+
+    php bin/console translation:extract app
+
+Extracting translations from a bundle
+-------------------------------------
+
+If you're using a bundle shipped with custom translations, you can extract
+them using ``external_translations_dir``.
+
+For example, with `FOSUserBundle<https://github.com/FriendsOfSymfony/FOSUserBundle/>`:
+
+.. code-block:: yaml
+
+    translation:
+      configs:
+        app:
+          external_translations_dir: ["%kernel.root_dir%/vendor/friendsofsymfony/user-bundle/Resources/translations"]

symfony/index.rst

@@ -62,8 +62,8 @@ Below is an example of configuration that is great to start with.
           excluded_names: ["*TestCase.php", "*Test.php"]
           excluded_dirs: [cache, data, logs]
 
-With the configuration above you may extract all translation key from your source
-code by running
+With the configuration above you may extract all translation keys from your
+source code by running
 
 .. code-block:: bash