utils: Allow to define cache directory separately

This setting was already used in Docker, now it is extended to
general.

See #2984

docs/admin/config.rst

@@ -267,6 +267,21 @@ You can pass additional arguments to :command:`borg create` when built-in backup
    :ref:`backup`,
    :doc:`borg:usage/create`
 
+.. setting:: CACHE_DIR
+
+CACHE_DIR
+---------
+
+.. versionadded:: 4.16
+
+Directory where Weblate stores cache files. Defaults to :file:`cache` subfolder
+in :setting:`DATA_DIR`.
+
+Change this to local or temporary filesystem if :setting:`DATA_DIR` is on a
+network filesystem.
+
+The Docker container uses a separate volume for this, see :ref:`docker-volume`.
+
 .. setting:: CSP_SCRIPT_SRC
 .. setting:: CSP_IMG_SRC
 .. setting:: CSP_CONNECT_SRC
@@ -409,6 +424,10 @@ The following subdirectories usually exist:
     Celery scheduler data, see :ref:`celery`.
 :file:`fonts`:
     User-uploaded  fonts, see :ref:`fonts`.
+:file:`cache`
+    Various caches, can be placed elsewhere using :setting:`CACHE_DIR`.
+
+    The Docker container uses a separate volume for this, see :ref:`docker-volume`.
 
 .. note::
 
@@ -426,7 +445,8 @@ Defaults to ``/home/weblate/data``, but it is expected to be configured.
 .. seealso::
 
     :ref:`file-permissions`,
-    :doc:`backup`
+    :doc:`backup`,
+    :setting:`CACHE_DIR`
 
 .. setting:: DATABASE_BACKUP
 

docs/admin/install/docker.rst

@@ -1601,8 +1601,8 @@ consist of name of your docker-compose directory, container, and volume names).
 In the container it is mounted as :file:`/app/data`.
 
 The cache volume is mounted as :file:`/app/cache` and is used to store static
-files. Its content is recreated on container startup and the volume can be
-mounted using ephemeral filesystem such as `tmpfs`.
+files and :setting:`CACHE_DIR`. Its content is recreated on container startup
+and the volume can be mounted using ephemeral filesystem such as `tmpfs`.
 
 When creating the volumes manually, the directories should be owned by UID 1000
 as that is user used inside the container.

weblate/settings_example.py

@@ -66,6 +66,7 @@
 # Data directory, you can use following for the development purposes:
 # os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), "data")
 DATA_DIR = "/home/weblate/data"
+CACHE_DIR = f"{DATA_DIR}/cache"
 
 # Local time zone for this installation. Choices can be found here:
 # http://en.wikipedia.org/wiki/List_of_tz_zones_by_name

weblate/settings_test.py

@@ -54,6 +54,7 @@
 else:
     BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 DATA_DIR = os.path.join(BASE_DIR, "data-test")
+CACHE_DIR = os.path.join(DATA_DIR, "cache")
 MEDIA_ROOT = os.path.join(DATA_DIR, "media")
 STATIC_ROOT = os.path.join(DATA_DIR, "static")
 CELERY_BEAT_SCHEDULE_FILENAME = os.path.join(DATA_DIR, "celery", "beat-schedule")

weblate/trans/models/_conf.py

@@ -9,6 +9,9 @@ class WeblateConf(AppConf):
     # Data directory
     DATA_DIR = None
 
+    # Cache directory
+    CACHE_DIR = None
+
     # Akismet API key
     AKISMET_API_KEY = None
 

weblate/utils/data.py

@@ -10,4 +10,6 @@
 
 def data_dir(component, *args):
     """Return path to data dir for given component."""
+    if component == "cache" and settings.CACHE_DIR:
+        return os.path.join(settings.CACHE_DIR, *args)
     return os.path.join(settings.DATA_DIR, component, *args)