postgres: Tweak and simplify upgrade script

roles/postgres/files/upgrade_pg.sh

@@ -3,47 +3,49 @@ set -e
 
 ## Set the old version that we want to upgrade from.
 TO_VERSION=$(pacman -Q postgresql | grep -Po '(?<=postgresql )[0-9]+\.[0-9]')
-to_major=$(echo "$TO_VERSION" | awk -F'.' '{print $1}')
-to_minor=$(echo "$TO_VERSION" | awk -F'.' '{print $2}')
-if [[ ${to_major} -ne 11 ]]; then
+
+to_major=${TO_VERSION%%.*}
+if (( $to_major != 12 )); then
 	# NOTE: When this happens you should check the changelog and add any
 	# necessary changes here. Then bump the version check.
-	echo "WARNING: major upgrade detected, aborting..."
+	echo "ERROR: major upgrade detected, aborting..."
 	exit 1
 fi
-export FROM_VERSION="$(cat /var/lib/postgres/data/PG_VERSION)"
 
-if [[ "$FROM_VERSION" == "$TO_VERSION" ]]; then
-	echo "WARNING: from and to versions are equal. Have you already updated?! Aborting..."
+FROM_VERSION="$(cat /var/lib/postgres/data/PG_VERSION)"
+if [[ $FROM_VERSION == $TO_VERSION ]]; then
+	echo "ERROR: from and to versions are equal. Have you already updated?! Aborting..."
 	exit 1
 fi
 
 # free space check
 used_space=$(df --local --output=pcent /var/lib/postgres/ | grep -Po '[0-9]{1,3}(?=%)')
-if [[ ${used_space} -ge 50 ]]; then
+if (( $used_space >= 50 )); then
 	echo "ERROR: not enough free space for upgrade with backup, aborting..."
 	exit 2
 fi
 
-pacman -S --needed postgresql-old-upgrade
-chown postgres:postgres /var/lib/postgres/
-if [[ -d "/var/lib/postgres/data-${FROM_VERSION}" ]]; then
-	echo "ERROR: backup data-${FROM_VERSION} directory already exists, aborting..."
+if [[ -d /var/lib/postgres/data-$FROM_VERSION ]]; then
+	echo "ERROR: backup data-$FROM_VERSION directory already exists, aborting..."
 	exit 3
 fi
-su - postgres -c "mv /var/lib/postgres/data /var/lib/postgres/data-${FROM_VERSION}"
+
+pacman -S --needed postgresql-old-upgrade
+chown postgres:postgres /var/lib/postgres/
+su - postgres -c "mv /var/lib/postgres/data /var/lib/postgres/data-$FROM_VERSION"
 su - postgres -c 'mkdir /var/lib/postgres/data'
-su - postgres -c "initdb --locale $LANG -E UTF8 -D /var/lib/postgres/data"
-vimdiff "/var/lib/postgres/data/pg_hba.conf" "/var/lib/postgres/data-${FROM_VERSION}/pg_hba.conf"
-vimdiff "/var/lib/postgres/data/postgresql.conf" "/var/lib/postgres/data-${FROM_VERSION}/postgresql.conf"
-for file in fullchain.pem chain.pem privkey.pem; do
-	cp -avx "/var/lib/postgres/data-${FROM_VERSION}/$file" "/var/lib/postgres/data/$file"
-done
+su - postgres -c 'initdb --locale en_US.UTF-8 -E UTF8 -D /var/lib/postgres/data'
+vimdiff /var/lib/postgres/{data,data-$FROM_VERSION}/pg_hba.conf
+vimdiff /var/lib/postgres/{data,data-$FROM_VERSION}/postgresql.conf
+cp -avxt /var/lib/postgres/data /var/lib/postgres/data-$FROM_VERSION/{fullchain,chain,privkey}.pem
+
 systemctl stop postgresql.service
-su - postgres -c "pg_upgrade -b /opt/pgsql-${FROM_VERSION}/bin/ -B /usr/bin/ -d /var/lib/postgres/data-${FROM_VERSION} -D /var/lib/postgres/data"
+su - postgres -c "pg_upgrade -b /opt/pgsql-$FROM_VERSION/bin/ -B /usr/bin/ \
+	-d /var/lib/postgres/data-$FROM_VERSION -D /var/lib/postgres/data"
 systemctl daemon-reload
 systemctl start postgresql.service
-su - postgres -c '/var/lib/postgres/analyze_new_cluster.sh'
+
+su - postgres -c /var/lib/postgres/analyze_new_cluster.sh
 # We probably want to manually delete things for now in case this script misses
 # some stuff
-#su - postgres -c '/var/lib/postgres/delete_old_cluster.sh'
+#su - postgres -c /var/lib/postgres/delete_old_cluster.sh