Merge ~morphis/snappy-hwe-snaps/+git/build-scripts:bug/check-deb-install-status into ~snappy-hwe-team/snappy-hwe-snaps/+git/build-scripts:master

[Simon Fels]

Check deb package install status before trying to install again

This removes the chance of having a conflict with an already locked deb database when we run the job multiple times. For the last tiny tiny chance of having a conflict we simply ignore the failing apt install call and let the build fail later on when it attempts to use one of the missing tools.

[System Enablement Bot (system-enablement-ci-bot)]

PASSED: Continuous integration, rev:b1c057b794d54f10dc416d872247e507cf2a2b9a
https://jenkins.canonical.com/system-enablement/job/generic-build-snap/889/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/generic-run-snap-spread-tests/595
    None: https://jenkins.canonical.com/system-enablement/job/generic-update-snap-mp/795/console

Click here to trigger a rebuild:
https://jenkins.canonical.com/system-enablement/job/generic-build-snap/889/rebuild

review: Approve (continuous-integration)

[Konrad Zapałowicz (kzapalowicz)]

Ack

review: Approve (code)

[Alfonso Sanchez-Beato (alfonsosanchezbeato)]

LGTM

review: Approve

[Jim Hodapp (jhodapp)]

Very nice enhancement. Thanks, looks good.

review: Approve

diff --git a/jobs/generic-run-snap-spread-tests b/jobs/generic-run-snap-spread-tests
index 9dd31d6..585deb9 100644
--- a/jobs/generic-run-snap-spread-tests
+++ b/jobs/generic-run-snap-spread-tests
@@ -70,7 +70,18 @@ $SSH sudo systemd-run --scope $REMOTE_WORKSPACE/build-spread.sh
 if [ $($SSH snap list | grep ubuntu-image | wc -l) -eq 0 ] ; then
     $SSH sudo snap install --edge --devmode ubuntu-image
 fi
-$SSH sudo apt install -y --force-yes kpartx qemu-kvm
+
+ensure_package_is_installed() {
+    status=$($SSH dpkg-query --show --showformat='${db:Status-Status}\n' "$1")
+    if [ "$status" != "installed" ] ; then
+        # Ignoring failures or for the tiny change of conflicting
+        # with another job running in parallel and trying the same.
+        $SSH sudo apt install -y --force-yes "$1" || true
+    fi
+}
+
+ensure_package_is_installed kpartx
+ensure_package_is_installed qemu-vkm
 
 cat << EOF > $WORKSPACE/run-spread-tests.sh
 #!/bin/bash