Add --incremental flag to backup-create

Add --incremental flag to backup-create and set the default
value to False. When the flag is passed it will create a
backup based on the last good known full/incremental backup.
If there is no previous backup a full backup will be created.

Change-Id: I6fcd60f6068dfb0145fa64248a2d8b3fdfc1004d
Depends-On: I96498180890b8b1692b1bac3b19988532f6eb077
Partial-Bug: #1607429

releasenotes/notes/incremental_backup-1910ded0fc3474a3.yaml

@@ -0,0 +1,6 @@
+features:
+  - The --incremental flag for backup-create will
+    add the ability to create incremental backup based
+    on last full or incremental backup. If no full or
+    incremental backup exists a new full backup will
+    be created.

trove/backup/models.py

@@ -48,7 +48,8 @@ class Backup(object):
                 operation=operation, datastore=instance.datastore.name)
 
     @classmethod
-    def create(cls, context, instance, name, description=None, parent_id=None):
+    def create(cls, context, instance, name, description=None,
+               parent_id=None, incremental=False):
         """
         create db record for Backup
         :param cls:
@@ -56,6 +57,9 @@ class Backup(object):
         :param instance:
         :param name:
         :param description:
+        :param parent_id:
+        :param incremental: flag to indicate incremental backup
+        based on previous backup
         :return:
         """
 
@@ -76,6 +80,7 @@ class Backup(object):
             ds = instance_model.datastore
             ds_version = instance_model.datastore_version
             parent = None
+            last_backup_id = None
             if parent_id:
                 # Look up the parent info or fail early if not found or if
                 # the user does not have access to the parent.
@@ -84,13 +89,22 @@ class Backup(object):
                     'location': _parent.location,
                     'checksum': _parent.checksum,
                 }
+            elif incremental:
+                _parent = Backup.get_last_completed(context, instance_id)
+                if _parent:
+                    parent = {
+                        'location': _parent.location,
+                        'checksum': _parent.checksum
+                    }
+                    last_backup_id = _parent.id
             try:
                 db_info = DBBackup.create(name=name,
                                           description=description,
                                           tenant_id=context.tenant,
                                           state=BackupState.NEW,
                                           instance_id=instance_id,
-                                          parent_id=parent_id,
+                                          parent_id=parent_id or
+                                          last_backup_id,
                                           datastore_version_id=ds_version.id,
                                           deleted=False)
             except exception.InvalidModelError as ex:
@@ -110,7 +124,6 @@ class Backup(object):
                            }
             api.API(context).create_backup(backup_info, instance_id)
             return db_info
-
         return run_with_quotas(context.tenant,
                                {'backups': 1},
                                _create_resources)

trove/backup/service.py

@@ -64,12 +64,13 @@ class BackupController(wsgi.Controller):
         name = data['name']
         desc = data.get('description')
         parent = data.get('parent_id')
+        incremental = data.get('incremental')
         context.notification = notification.DBaaSBackupCreate(context,
                                                               request=req)
         with StartNotification(context, name=name, instance_id=instance,
                                description=desc, parent_id=parent):
             backup = Backup.create(context, instance, name, desc,
-                                   parent_id=parent)
+                                   parent_id=parent, incremental=incremental)
         return wsgi.Result(views.BackupView(backup).data(), 202)
 
     def delete(self, req, tenant_id, id):

trove/common/apischema.py

@@ -523,7 +523,8 @@ backup = {
                     "description": non_empty_string,
                     "instance": uuid,
                     "name": non_empty_string,
-                    "parent_id": uuid
+                    "parent_id": uuid,
+                    "incremental": boolean_string
                 }
             }
         }

trove/tests/scenario/runners/backup_runners.py

@@ -107,9 +107,14 @@ class BackupRunner(TestRunner):
         return [database.name for database in
                 self.auth_client.databases.list(instance_id)]
 
-    def assert_backup_create(self, name, desc, instance_id, parent_id=None):
-        result = self.auth_client.backups.create(
-            name, instance_id, desc, parent_id=parent_id)
+    def assert_backup_create(self, name, desc, instance_id, parent_id=None,
+                             incremental=False):
+        if incremental:
+            result = self.auth_client.backups.create(
+                name, instance_id, desc, incremental=incremental)
+        else:
+            result = self.auth_client.backups.create(
+                name, instance_id, desc, parent_id=parent_id)
         self.assert_equal(name, result.name,
                           'Unexpected backup name')
         self.assert_equal(desc, result.description,
@@ -285,7 +290,8 @@ class BackupRunner(TestRunner):
         suffix = '_inc_2'
         self.backup_inc_2_info = self.assert_backup_create(
             self.BACKUP_NAME + suffix, self.BACKUP_DESC + suffix,
-            self.instance_info.id, parent_id=self.backup_inc_1_info.id)
+            self.instance_info.id, parent_id=self.backup_inc_1_info.id,
+            incremental=True)
 
     def run_wait_for_inc_backup_2(self):
         self._verify_backup(self.backup_inc_2_info.id)