MT#56542 Add support of custom mysql instance

For preparation of dumps (sql and json) it's useful to use separate
mysql instance which is run and handled manually.
So add support of such instance.
Add variable MYSQL_SOCKET which shows that we want to connect to custom
mysql instance via defined socket.
In such a case don't try to start a service mysql.

Change-Id: I3f40a3857125fc72158aabf277f892c7cd541bf6

ngcp-update-db-schema

@@ -38,8 +38,6 @@ if [ "${nodename}" = "unknown" ] ; then
   exit 1
 fi
 
-service mariadb start || true
-
 . /etc/default/ngcp-roles
 . /etc/default/ngcp-db
 
@@ -51,11 +49,17 @@ if [ ! -f "${SIPWISE_EXTRA_CNF}" ]; then
 fi
 
 declare -a MYSQL_OPTS=()
-MYSQL_OPTS+=("--defaults-extra-file=${SIPWISE_EXTRA_CNF}")
+if [[ -n "${MYSQL_SOCKET:-}" ]]; then
+  MYSQL_OPTS+=("-u" "root")
+  MYSQL_OPTS+=("-S" "${MYSQL_SOCKET}")
+else
+  service mariadb start || true
+  MYSQL_OPTS+=("--defaults-extra-file=${SIPWISE_EXTRA_CNF}")
+fi
 
 # check connection with sipwise user
 if ! mysql "${MYSQL_OPTS[@]}" -e 'SELECT 1;' &>/dev/null ; then
-  echo "Error: can't connect to local MariaDB port 3306 using '${SIPWISE_EXTRA_CNF}'" >&2
+  echo "Error: can't connect to MariaDB using '${MYSQL_OPTS[*]}'" >&2
   exit 1
 fi
 
@@ -166,18 +170,23 @@ apply_revs() {
     esac
   done
 
+  declare -a check_rev_opts=("--schema=db_schema")
+  if [[ -n "${MYSQL_SOCKET:-}" ]]; then
+    check_rev_opts+=("--socket=${MYSQL_SOCKET}")
+  fi
+
   # shellcheck disable=SC2086
   for missing_revision in \
     $( {
-        ngcp-check-rev-applied --schema db_schema --revision $revs                         | awk '/^No match for revision/ {print $5}' ;
-        ngcp-check-rev-applied --schema db_schema --revision $node_revs --node "$nodename" | awk '/^No match for revision/ {print $5}' ;
+        ngcp-check-rev-applied "${check_rev_opts[@]}" --revision $revs                         | awk '/^No match for revision/ {print $5}' ;
+        ngcp-check-rev-applied "${check_rev_opts[@]}" --revision $node_revs --node "$nodename" | awk '/^No match for revision/ {print $5}' ;
        } | sort -n -u ) ; do
     revision_file="$(find /usr/share/ngcp-db-schema/ -name "$missing_revision")"
 
     # execute the rev script iff there's no entry for the *current* host yet
     case "$revision_file" in
       *_not_replicated.up)
-        if ngcp-check-rev-applied --schema db_schema --revision "$missing_revision" --node "$nodename" | grep -q 'already executed' ; then
+        if ngcp-check-rev-applied "${check_rev_opts[@]}" --revision "$missing_revision" --node "$nodename" | grep -q 'already executed' ; then
           continue
         fi
         ;;