From dd41c56d864a0ecde74bf1981f4f70dec2189a43 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jose=20C=2E=20Mass=C3=B3n?=
 <939888+Abuelodelanada@users.noreply.github.com>
Date: Fri, 27 Sep 2024 08:48:16 -0300
Subject: [PATCH] observe on.start event to make start up process more robust
 (#292)

* observe on.start event to avoid intermediate erros status

* fix scenario tests
---
 src/charm.py               |  5 +++++
 tests/scenario/conftest.py |  2 ++
 tests/scenario/helpers.py  | 13 +++++++++++--
 tox.ini                    |  2 +-
 4 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/charm.py b/src/charm.py
index 8758a6ff..40a7a3cf 100755
--- a/src/charm.py
+++ b/src/charm.py
@@ -165,6 +165,7 @@ def __init__(self, *args):
 
         # Core lifecycle events
         self.framework.observe(self.on.config_changed, self._on_config_changed)
+        self.framework.observe(self.on.start, self._on_start)
 
         peer_ha_netlocs = [
             f"{hostname}:{self._ports.ha}"
@@ -487,6 +488,10 @@ def _on_config_changed(self, _):
         """Event handler for ConfigChangedEvent."""
         self._common_exit_hook(update_ca_certs=True)
 
+    def _on_start(self, _):
+        """Event handler for ConfigChangedEvent."""
+        self._common_exit_hook(update_ca_certs=True)
+
     def _on_peer_relation_joined(self, _):
         """Event handler for replica's RelationChangedEvent."""
         self._common_exit_hook()
diff --git a/tests/scenario/conftest.py b/tests/scenario/conftest.py
index e241438f..8193a4a8 100644
--- a/tests/scenario/conftest.py
+++ b/tests/scenario/conftest.py
@@ -23,6 +23,8 @@ def alertmanager_charm():
         is_ready=tautology,
     ), patch.object(WorkloadManager, "check_config", lambda *a, **kw: ("ok", "")), patch.object(
         WorkloadManager, "_alertmanager_version", property(lambda *_: "0.0.0")
+    ), patch(
+        "subprocess.run"
     ):
         yield AlertmanagerCharm
 
diff --git a/tests/scenario/helpers.py b/tests/scenario/helpers.py
index 06609e6a..caf19a37 100644
--- a/tests/scenario/helpers.py
+++ b/tests/scenario/helpers.py
@@ -1,11 +1,20 @@
 # Copyright 2023 Canonical Ltd.
 # See LICENSE file for licensing details.
 
-from scenario import Container, Context, PeerRelation, Relation, State
+from scenario import Container, Context, ExecOutput, PeerRelation, Relation, State
 
 
 def begin_with_initial_hooks_isolated(context: Context, *, leader: bool = True) -> State:
-    container = Container("alertmanager", can_connect=False)
+    container = Container(
+        "alertmanager",
+        can_connect=False,
+        exec_mock={
+            ("update-ca-certificates", "--fresh"): ExecOutput(  # this is the command we're mocking
+                return_code=0,  # this data structure contains all we need to mock the call.
+                stdout="OK",
+            )
+        },
+    )
     state = State(config={"config_file": ""}, containers=[container])
     peer_rel = PeerRelation("replicas")
 
diff --git a/tox.ini b/tox.ini
index b406e637..2d744f55 100644
--- a/tox.ini
+++ b/tox.ini
@@ -100,7 +100,7 @@ commands =
 description = Scenario tests
 deps =
     pytest
-    ops-scenario>=6
+    ops-scenario<7
     cosl
     -r{toxinidir}/requirements.txt
 commands =