Container continues to run silently when cos-alerter fails (#70)

* absent config handling

* remove python packages

* adding to change log

* adding unit test

* linting

* fix unit test

* Remove py-pkg python check in CI

* bump snap version

.github/workflows/pull-request.yaml

@@ -16,9 +16,7 @@ jobs:
         run: |
           pkg_version=$(grep -P -o 'version = "\d+\.\d+\.\d+"' pyproject.toml | grep -P -o '\d+\.\d+\.\d+')
           rock_version=$(grep -P -o 'version: "\d+\.\d+\.\d+"' rockcraft.yaml | grep -P -o '\d+\.\d+\.\d+')
-          rock_pkg_version=$(grep -P -o 'cos-alerter==\d+\.\d+\.\d+' rockcraft.yaml | grep -P -o '\d+\.\d+\.\d+')
           [ "${pkg_version}" == "${rock_version}" ]
-          [ "${rock_version}" == "${rock_pkg_version}" ]
   changelog-check:
     name: Changelog Check
     runs-on: ubuntu-latest

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.8.0] - 2024-03-07
+
+- Fixes container silently running by exiting with non-zero status when configuration file is missing. (#70).
+
 ## [0.7.0] - 2024-02-26
 
 - Client state is now retained on a graceful shutdown (#66).

cos_alerter/alerter.py

@@ -46,16 +46,23 @@ def _validate_hashes(self, clients):
     def reload(self):
         """Reload config values from the disk."""
         yaml = YAML(typ="rt")
+
+        # Load default configuration
         with open(
             os.path.join(os.path.dirname(os.path.realpath(__file__)), "config-defaults.yaml")
         ) as f:
             self.data = yaml.load(f)
-        with open(self.path, "r") as f:
-            try:
+
+        # Load user configuration
+        try:
+            with open(self.path, "r") as f:
                 user_data = yaml.load(f)
-            except DuplicateKeyError:
-                logger.critical("Duplicate client IDs found in COS Alerter config. Exiting...")
-                sys.exit(1)
+        except FileNotFoundError:
+            logger.critical("Config file not found. Exiting...")
+            sys.exit(1)
+        except DuplicateKeyError:
+            logger.critical("Duplicate client IDs found in COS Alerter config. Exiting...")
+            sys.exit(1)
 
         # Validate that keys are valid SHA-512 hashes
         if user_data and user_data.get("watch", {}).get("clients"):

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "cos-alerter"
-version = "0.7.0"
+version = "0.8.0"
 authors = [
   { name="Dylan Stephano-Shachter", email="dylan.stephano-shachter@canonical.com" }
 ]

rockcraft.yaml

@@ -1,17 +1,15 @@
 name: cos-alerter
 summary: A liveness checker for self-monitoring.
 description: Receive regular pings from the cos stack and alert when they stop.
-version: "0.7.0"  # NOTE: Make sure this matches `cos-alerter` below
-base: ubuntu:22.04
+version: "0.8.0"
+base: ubuntu@22.04
 license: Apache-2.0
 platforms:
   amd64:
 parts:
   cos-alerter:
     plugin: python
     source: .
-    python-packages:
-      - cos-alerter==0.7.0  # NOTE: Make sure this matches `version` above
     stage-packages:
       - python3-venv
 services:

snap/snapcraft.yaml

@@ -1,5 +1,5 @@
 name: cos-alerter
-version: '0.7.0'
+version: '0.8.0'
 summary: A watchdog alerting on alertmanager notification failures.
 license: Apache-2.0
 contact: simon.aronsson@canonical.com

tests/test_alerter.py

@@ -1,6 +1,7 @@
 # Copyright 2023 Canonical Ltd.
 # See LICENSE file for licensing details.
 
+import os
 import textwrap
 import threading
 import unittest.mock
@@ -29,6 +30,18 @@ def test_config_default_empty_file(fake_fs):
     assert config["watch"]["down_interval"] == 300
 
 
+def test_file_not_found_error(fake_fs):
+    with unittest.mock.patch("cos_alerter.alerter.logger") as mock_logger:
+        os.unlink("/etc/cos-alerter.yaml")
+        try:
+            config.reload()
+        except SystemExit as exc:
+            assert exc.code == 1
+            mock_logger.critical.assert_called_once_with("Config file not found. Exiting...")
+        else:
+            assert False
+
+
 def test_duplicate_key_error(fake_fs):
     duplicate_config = """
     watch: