Deprecate sqlite cache driver

sqlite cache driver and related configuration options will be
deprecated from this cycle.

Related blueprint centralized-cache-db

Change-Id: I0c1affff05a2a4c2838cfad2b637e7660b056eef

glance/image_cache/__init__.py

@@ -56,6 +56,11 @@ store the information about cached images:
   information. It also requires a filesystem that sets ``atime`` on the files
   when accessed.
 
+Deprecation warning:
+    * As centralized database will now be used for image cache management, the
+      use of `sqlite` database and driver will be dropped from 'E' (2025.1)
+      development cycle.
+
 Possible values:
     * sqlite
     * xattr

glance/image_cache/drivers/sqlite.py

@@ -36,8 +36,17 @@ from glance.image_cache.drivers import base
 
 LOG = logging.getLogger(__name__)
 
+DEPRECATION_REASON = """
+As centralized database will now be used for image cache management, the use
+of `sqlite` database and driver will be dropped from 'E' (2025.1)
+development cycle.
+"""
+
 sqlite_opts = [
     cfg.StrOpt('image_cache_sqlite_db', default='cache.db',
+               deprecated_for_removal=True,
+               deprecated_reason=DEPRECATION_REASON,
+               deprecated_since='Caracal (2024.1)',
                help=_("""
 The relative path to sqlite file database that will be used for image cache
 management.
@@ -111,6 +120,7 @@ class Driver(base.Driver):
         this method. If the store was not able to successfully configure
         itself, it should raise `exception.BadDriverConfiguration`
         """
+        LOG.warning(_(DEPRECATION_REASON))
         super(Driver, self).configure()
 
         # Create the SQLite database that will hold our cache attributes

releasenotes/notes/deprecate-sqlite-cache-driver-1f5f67862f56e0ba.yaml

@@ -0,0 +1,11 @@
+---
+deprecations:
+  - |
+    The Glance cache driver ``sqlite`` is deprecated in this release and
+    is subject to removal at the beginning of the `E`  (2025.1)
+    development cycle, following the `OpenStack standard deprecation policy
+    <https://governance.openstack.org/reference/tags/assert_follows-standard-deprecation.html>`_.
+
+    The configuration option ``image_cache_sqlite_db`` related to ``sqlite``
+    cache driver is also deprecated and is subject to removal at the
+    beginning of `E` (2025.1) development cycle.