mariadb: Init script improvements

Update init script so other user/group can be used. Also make sure that
init script can actually create an empty database instead of forcing the
user to do it by hand. Other new feature is taking care of migration
of the database when upgrading the database.

Signed-off-by: Michal Hrusecky <michal.hrusecky@turris.com>

utils/mariadb/files/mysqld.config

@@ -1,5 +1,13 @@
 
 config mysqld 'general'
-	option enabled '0'			# 0 - disabled, 1 - enabled
-	option options '--syslog'		# Options passed to mysqld_safe
+    # Unless enable, MariaDB will not start without this
+	option enabled '0'
+    # User to run MariaDB as
+    option user 'mariadb'
+    # Group to run MariaDB
+    option group 'mariadb'
+    # If there is now database, create an empty one automatically
+    option init '1'
+    # If upgrading old database, run mysql_upgrade during restart
+    option upgrade '1'
 

utils/mariadb/files/mysqld.init

@@ -9,8 +9,6 @@ STOP=10
 USE_PROCD=1
 
 NAME=mysqld
-my_user="mariadb"
-my_group="mariadb"
 
 LOGGER="/usr/bin/logger -p user.err -s -t $NAME --"
 [ -x "$LOGGER" ] || LOGGER="echo"
@@ -70,14 +68,19 @@ start_service() {
 	conf=/etc/mysql/my.cnf
 	logdir=/var/log/mysql
 	rundir=/var/run/mysqld
+	version="$(mysqld --version | sed -n 's|.*Ver[[:blank:]]*\([0-9.]*\)-.*|\1|p')"
 
-	hint="please fix your server configuration in /etc/mysql/"
- 
+	# Few basic checks
 	if [ ! -x "$MYSQLD" ]; then
 		$LOGGER "$MYSQLD is missing"
 		exit 1
 	fi
 
+	if [ -z "$version" ]; then
+		$LOGGER "Can't get MariaDB version, something is seriously wrong"
+		exit 1
+	fi
+
 	if [ ! -r "$conf" ]; then
 		$LOGGER "$conf cannot be read"
 		exit 1
@@ -88,34 +91,50 @@ start_service() {
 		exit 0
 	fi
 
+	# Get various config options
 	config_load "$NAME"
-
+	config_get my_user general user "mariadb"
+	config_get my_group general group "mariadb"
 	config_get_bool enabled general enabled 0
+	config_get_bool init_db general init 1
+	config_get_bool autoupgrade general upgrade 1
+	config_get options general options
+
 	# shellcheck disable=SC2154
 	if [ "$enabled" -eq 0 ]; then
 		$LOGGER "service not enabled in /etc/config/$NAME"
 		exit 1
 	fi
 
-	config_get options general options
-
 	datadir="$(mysqld_get_param datadir)"
 	tmpdir="$(mysqld_get_param tmpdir)"
+	sockdir="$(dirname "$(mysqld_get_param socket)")"
 
+	# Make sure we have a working database in datadir
 	if [ ! -f "$datadir/mysql/tables_priv.MAD" ]; then
 		args="--force"
 		basedir="$(mysqld_get_param basedir)"
 		[ -n "$basedir" ] && args="$args --basedir=$basedir"
 
-		$LOGGER "Cannot detect privileges table. You might need to run"
-		$LOGGER "'mysql_install_db \"$args\"'"
-		$LOGGER "to initialize the system tables."
-		$LOGGER "Then hand it ower to MariaDB user"
-		$LOGGER "'chown -Rh \"$my_user:$my_group\" \"$datadir\"'"
+		# shellcheck disable=SC2154
+		if [ "$init_db" -gt 0 ]; then
+			# shellcheck disable=SC2154
+			mysql_install_db $args --skip-name-resolve --skip-test-db --datadir="$datadir" || exit 1
+			echo "$version" > "$datadir"/.version
+			chown -Rh "$my_user:$my_group" "$datadir"
+		else
+			$LOGGER "Cannot detect privileges table. You might need to run"
+			$LOGGER "'mysql_install_db \"$args\"'"
+			$LOGGER "to initialize the system tables."
+			$LOGGER "Then hand it ower to MariaDB user"
+			# shellcheck disable=SC2154
+			$LOGGER "'chown -Rh \"$my_user:$my_group\" \"$datadir\"'"
 		exit 1
+		fi
 	fi
 
-	for i in "$logdir" "$rundir" "$tmpdir" "$datadir"; do
+	# Make sure all required directories exists and have correct rights
+	for i in "$logdir" "$rundir" "$sockdir"; do
 		opts="-m 0750"
 		if ! [ -e "$i" ]; then
 			# $rundir needs to be accessible for
@@ -125,10 +144,44 @@ start_service() {
 			fi
 			# shellcheck disable=SC2086
 			mkdir -p $opts "$i"
-			[ -d "$i" ] && chown -Rh "$my_user:$my_group" "$i"
 		fi
+		# shellcheck disable=SC2154
+		[ -d "$i" ] && chown -Rh "$my_user:$my_group" "$i"
 	done
 
+	# Migration from old versions
+	# shellcheck disable=SC2154
+ 	if [ "$(cat "$datadir"/.version 2> /dev/null)" \!= "$version" ] && [ "$autoupgrade" -gt 0 ]; then
+		# Start upgrade instance without credentials
+ 		sudo -u "$my_user" mysqld --skip-networking --skip-grant-tables --socket=/tmp/mysql_upgrade.sock &
+		PID="$!"
+ 		i=0
+		# Wait for upgrade instance of db to start
+ 		while [ "$i" -lt 15 ] && test \! -S /tmp/mysql_upgrade.sock; do
+ 			sleep 1
+ 			i="$((i + 1))"
+ 		done
+ 		[ -S /tmp/mysql_upgrade.sock ] || {
+			$LOGGER "Failed to start upgrading instance of MariaDB."
+			exit 1
+		}
+		# Upgrade the database
+ 		mysql_upgrade --upgrade-system-tables --socket=/tmp/mysql_upgrade.sock
+ 		echo "$version" > "$datadir"/.version
+		# Stop the upgrade instance
+ 		kill "$PID"
+ 		i=0
+ 		while [ "$i" -lt 60 ] && grep -q mysql "/proc/$PID/cmdline"; do
+ 			sleep 1
+ 			[ "$i" -lt 30 ] || kill "$PID"
+ 			i="$((i + 1))"
+ 		done
+		# Use force
+ 		if grep -q mysql "/proc/$PID/cmdline"; then
+ 			kill -9 "$PID"
+ 		fi
+ 	fi
+
 	# Start daemon
 	procd_open_instance