Improve exceptions handling and add can_connect guards

lib/charms/loki_k8s/v1/loki_push_api.py

@@ -527,7 +527,7 @@ def _alert_rules_error(self, event):
 
 # Increment this PATCH version before using `charmcraft publish-lib` or reset
 # to 0 if you are raising the major API version
-LIBPATCH = 11
+LIBPATCH = 12
 
 PYDEPS = ["cosl"]
 
@@ -2475,6 +2475,9 @@ def disable_inactive_endpoints(
         container: Container, active_endpoints: Dict[str, str], topology: JujuTopology
     ):
         """Disable forwarding for inactive endpoints by checking against the Pebble plan."""
+        if not container.can_connect():
+            return
+
         pebble_layer = container.get_plan().to_dict().get("log-targets", None)
         if not pebble_layer:
             return
@@ -2501,6 +2504,9 @@ def enable_endpoints(
         container: Container, active_endpoints: Dict[str, str], topology: JujuTopology
     ):
         """Enable forwarding for the specified Loki endpoints."""
+        if not container.can_connect():
+            return
+
         layer = Layer(
             {  # pyright: ignore
                 "log-targets": _PebbleLogClient._build_log_targets(

src/charm.py

@@ -566,6 +566,9 @@ def _update_config(self, config: dict) -> bool:
         return False
 
     def _update_cert(self):
+        # If Pebble is not ready, we do not proceed.
+        # This code will end up running anyway when Pebble is ready, because
+        # it will eventually be called from the `_configure()` method.
         if not self._loki_container.can_connect():
             return
 

tests/unit/helpers.py

@@ -23,3 +23,6 @@ def __init__(self, args):
 
     def wait_output(self):
         return ("v0.1.0", "")
+
+    def wait(self):
+        return ("v0.1.0", "")

tox.ini

@@ -33,7 +33,7 @@ deps =
     black
     ruff
 commands =
-    ruff --fix {[vars]all_path}
+    ruff check --fix {[vars]all_path}
     black {[vars]all_path}
 
 # codespell pinned cause version 2.3.0 mistakenly considers joined words such as "assertIn" invalid
@@ -46,7 +46,7 @@ deps =
 commands =
     codespell {[vars]lib_path}
     codespell . --skip .git --skip .tox --skip build --skip lib --skip venv --skip .mypy_cache
-    ruff {[vars]all_path}
+    ruff check {[vars]all_path}
     black --check --diff {[vars]all_path}
 
 [testenv:static-{charm,lib}]