backup postgresql db handling

tasks/backup.yaml

@@ -17,3 +17,10 @@
     > "{{nextcloud_backup_directory}}/{{_nextcloud_actual_version}}/database.mysql"
   args:
     stdin: "{{nextcloud_database_pass}}"
+  when: nextcloud_database_type == "mysql"
+
+- name: drop postgresql database
+  shell: sudo -u postgres pg_dump -O
+    > "{{nextcloud_backup_directory}}/{{_nextcloud_actual_version}}/database.pgsql"
+  delegate_to: "{{ (nextcloud_database_host != 'localhost') | ternary(nextcloud_database_host,inventory_hostname) }}"
+  when: nextcloud_database_type == "postgresql"