[pmg-devel] [PATCH pmg-api] d/maintscripts: prevent aborting on errors in some commands

[Stoiko Ivanov <s.ivanov@proxmox.com>]

in case something goes wrong it is often better to not leave the
packaging state broken.

failure in the commands masked by this patch are either transient
(pmgconfig sync -restart 1 failing when services are masked), or will
be noticed quite instantly (failed database or config initialization
upon first install)

the deb-systemd-invoke change was based on a quick grep in
/var/lib/dpkg/info on my system

I quickly considered masking even more errors (e.g. related to the ucf
handling) - but they don't seem to cause issues (in the past 3 years)
- and if something breaks there it is probably worth to get a report

reported in our community forum:
https://forum.proxmox.com/threads/.125088/

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
---
This patch should fix the issue - I considered the suggestions discussed
off-list with making the reload command not fail when the config-rewrite
issues it - but doing so in general feels wrong.
Ignoring a failure if a service is masked did not seem robust - e.g.
masking 'postfix.service' does not result in 'postfix@-' being masked as
well, and still a reload of 'postfix@-' service fails (and explicitly
listing this one edge-case felt a bit brittle)
Finally not erroring out in `pmgconfig sync -restart 1` felt off as it's
the direct entry point for the user - and masking an error should be the
caller's responsibility

Reproduced the issue from the forum with a 7.2 installation and masking
all services as in the upgrade guide[0] before upgrading and with this
patch the upgrade does not result in a broken dpkg state anymore

[0] https://pmg.proxmox.com/wiki/index.php/Upgrade_from_6.x_to_7.0

 debian/postinst | 6 +++---
 debian/prerm    | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/debian/postinst b/debian/postinst
index 690d10d..d4d434a 100644
--- a/debian/postinst
+++ b/debian/postinst
@@ -89,11 +89,11 @@ case "$1" in
 
         if test ! -e /proxmox_install_mode ; then
 
-            pmgconfig init
-            pmgdb init
+            pmgconfig init || true
+            pmgdb init || true
 
             ucf_register_templates
-            pmgconfig sync --restart
+            pmgconfig sync --restart || true
 
             if [ -z "$2" ]; then
                 if systemctl --quiet is-active pmgpolicy.service ; then
diff --git a/debian/prerm b/debian/prerm
index 4d0ca06..f9b6f3a 100644
--- a/debian/prerm
+++ b/debian/prerm
@@ -19,7 +19,7 @@ case "$1" in
 esac
 
 if [ -d /run/systemd/system ] && [ "$1" = remove ]; then
-    deb-systemd-invoke stop pmgproxy.service pmgdaemon.service >/dev/null
+    deb-systemd-invoke stop pmgproxy.service pmgdaemon.service >/dev/null || true
 fi
 
 # dh_installdeb will replace this with shell code automatically
-- 
2.30.2