mgr/cephadm: update get_container_image function

Update get_container_image to be a public function as it is only called
by code outside of its class. Add a 2nd boolean argument that forces the
use of a ceph image regardless of what the passed service name is.
This new flag will be used to create ceph image based sidecars for other
services.

Signed-off-by: John Mulligan <[email protected]>
(cherry picked from commit d1815c6)

Resolves: rhbz#2364414

Author: phlogistonjohn

src/pybind/mgr/cephadm/module.py

@@ -1719,8 +1719,19 @@ def _client_keyring_rm(
         self._kick_serve_loop()
         return HandleCommandResult()
 
-    def _get_container_image(self, daemon_name: str, use_current_daemon_image: bool = False) -> Optional[str]:
-        daemon_type = daemon_name.split('.', 1)[0]  # type: ignore
+    def get_container_image(
+        self,
+        daemon_name: str,
+        use_current_daemon_image: bool = False,
+        force_ceph_image: bool = False,
+    ) -> Optional[str]:
+        """Return an image for the given daemon_name.
+        If `use_current_daemon_image` is set the function will try to re-use
+        the image for an existing service.
+        If force_ceph_image is true the daemon_name will be ignored and the
+        main ceph container image will be returned.
+        """
+        daemon_type = daemon_name.split('.', 1)[0]
         image: Optional[str] = None
         # Try to use current image if specified. This is necessary
         # because, if we're reconfiguring the daemon, we can
@@ -1740,7 +1751,7 @@ def _get_container_image(self, daemon_name: str, use_current_daemon_image: bool
             except OrchestratorError:
                 self.log.debug(f'Could not find daemon {daemon_name} in cache '
                                'while searching for its image')
-        if daemon_type in CEPH_IMAGE_TYPES:
+        if daemon_type in CEPH_IMAGE_TYPES or force_ceph_image:
             # get container image
             image = str(self.get_foreign_ceph_option(
                 utils.name_to_config_section(daemon_name),

src/pybind/mgr/cephadm/serve.py

@@ -1903,7 +1903,7 @@ async def _run_cephadm(self,
         # Skip the image check for daemons deployed that are not ceph containers
         if not str(entity).startswith(bypass_image):
             if not image and entity is not cephadmNoImage:
-                image = self.mgr._get_container_image(
+                image = self.mgr.get_container_image(
                     entity,
                     use_current_daemon_image=use_current_daemon_image
                 )