bundles/postgresql: do a database dump before backing up the database

bundles/postgresql/files/backup-pre-hook

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+target="/var/tmp/postgresdumps"
+
+pg_dumpall --globals-only | gzip --quiet --rsyncable >"$target/globals.sql.gz"
+
+% for db in sorted(databases):
+pg_dump -C "${db}" | gzip --quiet --rsyncable >"$target/db_${db}.sql.gz"
+% endfor

bundles/postgresql/items.py

@@ -56,6 +56,19 @@ files = {
     },
 }
 
+# FIXME currently we do not have a mechanism to use snapshot-backups of
+# zfs datasets.
+if True: # not node.has_bundle('zfs') and node.has_bundle('backup-client'):
+    files['/etc/backup-pre-hooks.d/90-postgresql-dump-all'] = {
+        'source': 'backup-pre-hook',
+        'content_type': 'mako',
+        'context': {
+            'databases': node.metadata.get('postgresql', {}).get('databases', {}).keys(),
+        },
+        'mode': '0700',
+    }
+    directories['/var/tmp/postgresdumps'] = {}
+
 postgres_roles = {
     'root': {
         'password': repo.vault.password_for('{} postgresql root'.format(node.name)),

bundles/postgresql/metadata.py

@@ -2,6 +2,9 @@ defaults = {
     'backups': {
         'paths': {
             '/var/lib/postgresql',
+
+            # FIXME
+            '/var/tmp/postgresdumps',
         },
     },
     'icinga2_api': {
@@ -32,6 +35,9 @@ if node.has_bundle('zfs'):
             },
         },
     }
+# FIXME
+#else:
+#    defaults['backups']['paths'].add('/var/tmp/postgresdumps')
 
 
 @metadata_reactor.provides(