Add option to load database dump from the sql scripts

Loosely copied from the domjudge-scripts repo to add
an option for reloading an existing dump.

We've used this sort of script for multiple years, this makes sure we
have the right setups around the tables by making sure the database is
in a current state (users etc.).

Co-authored-by: Jaap Eldering <[email protected]>

Author: vmcj

doc/manual/install-domserver.rst

@@ -35,14 +35,14 @@ For your convenience, the following command will install the necessary
 software on the DOMjudge server as mentioned above when using Debian
 GNU/Linux, or one of its derivative distributions like Ubuntu::
 
-  sudo apt install libcgroup-dev make acl zip unzip mariadb-server apache2 \
+  sudo apt install libcgroup-dev make acl zip unzip pv mariadb-server apache2 \
         php php-fpm php-gd php-cli php-intl php-mbstring php-mysql \
         php-curl php-json php-xml php-zip composer ntp python3-yaml
 
 The following command can be used on Fedora, and related distributions like
 Red Hat Enterprise Linux and Rocky Linux (before V9)::
 
-  sudo dnf install libcgroup-devel make acl zip unzip mariadb-server httpd \
+  sudo dnf install libcgroup-devel make acl zip unzip pv mariadb-server httpd \
         php-gd php-cli php-intl php-mbstring php-mysqlnd php-fpm \
         php-xml php-zip composer chronyd python3-pyyaml
 

sql/dj_setup_database.in

@@ -36,6 +36,7 @@ Commands:
   install-loadtest configure for load testing. WARNING: CREATES A LOT OF EXTRA ITEMS!
   upgrade          upgrade MySQL database schema to current version
   dump [filename]  backup the current database to file (without .sql.gz suffix)
+  load [filename]  load a backup from file (without .sql.gz suffix), REMOVES ALL PREVIOUS DATA!
 
 Options:
   -u <user>  connect to MySQL with DB admin <user>
@@ -241,6 +242,19 @@ install_examples()
 	( cd "$EXAMPLEPROBDIR" && yes y | "$BINDIR"/import-contest )
 }
 
+uninstall_helper()
+{
+	read_dbpasswords
+	remove_db_users
+}
+
+create_db_users_helper()
+{
+	read_dbpasswords
+	create_db_users
+	verbose "Created empty database and users."
+}
+
 create_database_dump () {
 	sudo mysqldump $(mysql_options) --opt --skip-lock-tables domjudge | pv | gzip > "$DATABASEDUMPDIR/${1}.sql.gz"
 }
@@ -301,8 +315,7 @@ genpass)
 	;;
 
 uninstall)
-	read_dbpasswords
-	remove_db_users
+	uninstall_helper
 	;;
 
 install-examples)
@@ -321,9 +334,7 @@ install-loadtest)
 	;;
 
 create-db-users)
-	read_dbpasswords
-	create_db_users
-	verbose "Created empty database and users."
+	create_db_users_helper
 	;;
 
 bare-install|install)
@@ -386,6 +397,41 @@ dump)
 	exit 0
 	;;
 
+load)
+	choice=""
+	DUMPNAME="$2"
+	if [ -z "$DUMPNAME" ]; then
+		set -- $(ls $DATABASEDUMPDIR)
+		ind=0
+		while true; do
+			read -p "Which database should be loaded? " db
+			ind=0
+			for i in $@; do
+				if [ "$ind" = "$db" ]; then
+					choice="$i"
+					break
+				fi
+				: $((ind+=1))
+			done
+			if [ -n "$choice" ]; then
+				break
+			fi
+		done
+	else
+		choice="${DUMPNAME}.sql.gz"
+	fi
+	FILE="$DATABASEDUMPDIR/${choice}"
+
+	if [ ! -f "${FILE}" ]; then
+		echo "Error: file ${FILE} not found."
+		exit 1
+	fi
+
+	uninstall_helper
+	create_db_users_helper
+	pv "${FILE}" | gunzip | mysql domjudge
+	;;
+
 *)
 	echo "Error: Unknown subcommand '$1'"
 	usage