add pg backup script

compose.yml

@@ -98,6 +98,10 @@ services:
 
   db:
     image: postgres:17
+    configs:
+        - source: pg_backup
+          target: /pg_backup.sh
+          mode: 0555
     healthcheck:
       test: [ "CMD", "pg_isready", "-q", "-d", "postgres", "-U", "liberaforms" ]
       timeout: 45s
@@ -107,6 +111,11 @@ services:
       POSTGRES_USER: liberaforms
       POSTGRES_DB: liberaforms
       POSTGRES_PASSWORD_FILE: /run/secrets/db_password
+    deploy:
+      labels:
+        backupbot.backup.pre-hook: "/pg_backup.sh backup"
+        backupbot.backup.volumes.postgres.path: "backup.sql"
+        backupbot.restore.post-hook: '/pg_backup.sh restore'
     volumes:
       - db:/var/lib/postgresql/data
     secrets:
@@ -145,3 +154,6 @@ configs:
   nginx_conf:
     name: ${STACK_NAME}_nginx_conf_${NGINX_CONFIG_VERSION}
     file: nginx.conf
+  pg_backup:
+    name: ${STACK_NAME}_pg_backup_${PG_BACKUP_VERSION}
+    file: pg_backup.sh

pg_backup.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+
+set -e
+
+BACKUP_FILE='/var/lib/postgresql/data/backup.sql'
+
+function backup {
+  export PGPASSWORD=$(cat /run/secrets/db_password)
+  pg_dump -U ${POSTGRES_USER} ${POSTGRES_DB} > $BACKUP_FILE
+}
+
+function restore {
+    cd /var/lib/postgresql/data/
+    restore_config(){
+        # Restore allowed connections
+        cat pg_hba.conf.bak > pg_hba.conf
+        su postgres -c 'pg_ctl reload'
+    }
+    # Don't allow any other connections than local
+    cp pg_hba.conf pg_hba.conf.bak
+    echo "local all all trust" > pg_hba.conf
+    su postgres -c 'pg_ctl reload'
+    trap restore_config EXIT INT TERM
+
+    # Recreate Database
+    psql -U ${POSTGRES_USER} -d postgres -c "DROP DATABASE ${POSTGRES_DB} WITH (FORCE);" 
+    createdb -U ${POSTGRES_USER} ${POSTGRES_DB}
+    psql -U ${POSTGRES_USER} -d ${POSTGRES_DB} -1 -f $BACKUP_FILE
+
+    trap - EXIT INT TERM
+    restore_config
+}
+
+$@