[neon/neon/settings/Neon/release-lts] /: add a unit to ensure the apt cache gets auto cleaned daily

[Harald Sitter]

Git commit 75e0a8133e515b0d27e694a53664124304d5fb8d by Harald Sitter.
Committed on 03/05/2021 at 11:02.
Pushed by sitter into branch 'Neon/release-lts'.

add a unit to ensure the apt cache gets auto cleaned daily

there's really no reason not to do it. chances are something does it on
ubuntu that we either disabled/removed/donthave. it's unreasonable to
keep forever growing caches on a desktop system

M  +1    -0    debian/neon-settings-2.install
M  +10   -1    debian/rules
A  +21   -0    lib/systemd/system/neon-apt-clean.service
A  +13   -0    lib/systemd/system/neon-apt-clean.timer

https://invent.kde.org/neon/neon/settings/commit/75e0a8133e515b0d27e694a53664124304d5fb8d

diff --git a/debian/neon-settings-2.install b/debian/neon-settings-2.install
index 7c0337f..5534f43 100644
--- a/debian/neon-settings-2.install
+++ b/debian/neon-settings-2.install
@@ -1,2 +1,3 @@
 etc/
 usr/
+lib/
diff --git a/debian/rules b/debian/rules
index 626da9f..d3f901b 100755
--- a/debian/rules
+++ b/debian/rules
@@ -1,7 +1,7 @@
 #!/usr/bin/make -f
 # SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
 # SPDX-FileCopyrightText: 2016 Jonathan Riddell <jr at jriddell.org>
-# SPDX-FileCopyrightText: 2018-2020 Harald Sitter <sitter at kde.org>
+# SPDX-FileCopyrightText: 2018-2021 Harald Sitter <sitter at kde.org>
 
 export DH_VERBOSE=1
 
@@ -12,6 +12,15 @@ override_dh_usrlocal:
 	true
 
 override_dh_installsystemd:
+	# Random safe guard. dh_installsystemd doesn't handle /usr/lib/systemd same as /lib/systemd 🙄
+	if find debian/neon-settings-*/lib/systemd/ -type f -not \( -name '*.service' -or -name '*.timer' -or -name '*.slice' \) | grep '.'; then \
+		echo "   !!! Only put unit files in /lib/systemd, everything else in /usr/lib/systemd!"; \
+		exit 1; \
+	fi
+
+	# Perferrably use lib/systemd/system/ instead of placing units in debian/
+	# Also mind https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=987989
+	dh_installsystemd
 	dh_installsystemd --no-start --name=neon-update-calamares-groups
 	dh_installsystemd --no-start --name=neon-flathub
 	dh_installsystemd --no-start --name=neon-packagekit-offline-update-policy
diff --git a/lib/systemd/system/neon-apt-clean.service b/lib/systemd/system/neon-apt-clean.service
new file mode 100644
index 0000000..9de3415
--- /dev/null
+++ b/lib/systemd/system/neon-apt-clean.service
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+# SPDX-FileCopyrightText: 2021 Harald Sitter <sitter at kde.org>
+
+[Unit]
+Description=Apt cache cleanup
+ConditionACPower=true
+# No point starting (and failing) when the lock is currently held.
+ConditionPathExists=!/var/cache/apt/archives/lock
+# If packagekit is running wait until it is done. Otherwise we might block it with a temporary apt lock.
+After=packagekit.service
+
+[Service]
+ExecStart=/usr/bin/apt-get autoclean
+Nice=9
+IOSchedulingPriority=6
+# With our niceness we need to ensure the process doesn't get starved and never terminates.
+# Also, be quick about it. Clean holds the lock - the quicker it is, the better!
+# If it doesn't finish within this time frame because of IO contention or general drive speed we'll simply continue
+# cleaning the next day and so and so forth until eventually everything is clean again and the daily cleanup is
+# completing in a more reasonable time frame from thereon out.
+RuntimeMaxSec=5 minutes
diff --git a/lib/systemd/system/neon-apt-clean.timer b/lib/systemd/system/neon-apt-clean.timer
new file mode 100644
index 0000000..6ea70b1
--- /dev/null
+++ b/lib/systemd/system/neon-apt-clean.timer
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+# SPDX-FileCopyrightText: 2021 Harald Sitter <sitter at kde.org>
+
+[Unit]
+Description=Apt cache cleanup timer
+
+[Timer]
+Persistent=true
+OnCalendar=daily
+RandomizedDelaySec=16 hours
+
+[Install]
+WantedBy=timers.target