gitea: try to automate backup with backrest pre/post hooks and pgdump

hosts/home-morefine/docker/gitea/dump_db.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+set -e
+
+CONTAINER="gitea_pg_db"
+USER="gitea"
+DB="gitea"
+BACKUP_DIR="/srv/backups/pgdumps/gitea"
+TMP_FILE="$BACKUP_DIR/pg.dump.tmp"
+FINAL_FILE="$BACKUP_DIR/pg.dump"
+
+echo "Starting [$DB] pg_dump..."
+
+mkdir -p "$BACKUP_DIR"
+
+# remove old backup file
+rm -f "$TMP_FILE" "$FINAL_FILE"
+
+docker exec -t "$CONTAINER" \
+  sh -lc "pg_dump -U $USER -d $DB -Fc -Z 0 --no-owner --no-privileges" \
+  > "$TMP_FILE"
+
+mv "$TMP_FILE" "$FINAL_FILE"
+
+echo "Done: [$DB] backup saved to $FINAL_FILE"