Merge ~hloeung/ubuntu-repository-cache:reduce-cron-spam into ubuntu-repository-cache:master

[Haw Loeung]

Reduce cron spam with update-notifier-common too - LP:1940011

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[Loïc Gomez (kotodama)]

review: Approve (+1)

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision c6d063cbb3a8112e7012dba75f0debcbf88b623c

diff --git a/reactive/ubuntu_repository_cache.py b/reactive/ubuntu_repository_cache.py
index 5ec909d..cadfd89 100755
--- a/reactive/ubuntu_repository_cache.py
+++ b/reactive/ubuntu_repository_cache.py
@@ -374,7 +374,7 @@ def update_systemd_mtr(etc_systemd_path='/etc/systemd/system'):
 
 
 @reactive.when_not('reduce-cron-spam.configured')
-def reduce_cron_spam(etc_path='/etc'):
+def reduce_cron_spam(etc_path='/etc'):  # NOQA: C901
     # https://bugs.launchpad.net/ubuntu/+source/ieee-data/+bug/1922960
     ieee_data_path = os.path.join(etc_path, 'cron.monthly/ieee-data')
     if os.path.exists(ieee_data_path):
@@ -425,6 +425,20 @@ systemd/system/snap.*.service
 '''
         _write_file('\n'.join(new) + ignore_snaps, bzrignore_path, perms=0o600)
 
+    # https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1940011
+    update_notifier_cron_path = os.path.join(etc_path, 'cron.weekly/update-notifier-common')
+    if os.path.exists(update_notifier_cron_path):
+        update_notifier_cron = []
+        with open(update_notifier_cron_path, 'r', encoding='utf-8') as f:
+            update_notifier_cron = f.read().split('\n')
+        new = []
+        for line in update_notifier_cron:
+            if line.endswith('/usr/lib/ubuntu-release-upgrader/release-upgrade-motd'):
+                new.append(line + ' >/dev/null')
+            else:
+                new.append(line)
+        _write_file('\n'.join(new), update_notifier_cron_path, perms=0o755)
+
     reactive.set_flag('reduce-cron-spam.configured')
 
 
diff --git a/tests/unit/test_ubuntu_repository_cache.py b/tests/unit/test_ubuntu_repository_cache.py
index 5f70bb4..0bac880 100644
--- a/tests/unit/test_ubuntu_repository_cache.py
+++ b/tests/unit/test_ubuntu_repository_cache.py
@@ -179,6 +179,19 @@ systemd/system/snap.*.service
             got = f.read()
         self.assertEqual(want2, got)
 
+    @mock.patch('charms.reactive.set_flag')
+    def test_reduce_cron_spam_update_notifier(self, set_flag):
+        update_notifier_cron_path = os.path.join(self.tmpdir, 'cron.weekly/update-notifier-common')
+        os.mkdir(os.path.join(self.tmpdir, 'cron.weekly'))
+        with open(update_notifier_cron_path, 'w') as f:
+            f.write('    /usr/lib/ubuntu-release-upgrader/release-upgrade-motd\n')
+        ubuntu_repository_cache.reduce_cron_spam(self.tmpdir)
+        set_flag.assert_called_once_with('reduce-cron-spam.configured')
+        want = '    /usr/lib/ubuntu-release-upgrader/release-upgrade-motd >/dev/null\n'
+        with open(update_notifier_cron_path, 'r', encoding='utf-8') as f:
+            got = f.read()
+        self.assertEqual(want, got)
+
     @mock.patch('charmhelpers.core.hookenv.leader_get')
     @mock.patch('charms.reactive.set_flag')
     def test_set_active(self, set_flag, leader_get):