Add detach-replica support

Add a PATCH route to unset the slave_of property on an instance, i.e. to
detach a replica from its replication source.

Rename existing 'detach_replication_slave' functions to 'detach_replica'
to be consistent with the python-troveclient.

Add test case to tests/api/replication.py.

Partially Implements: blueprint replication-v1

Change-Id: I3596a3b76cc484b42db38f02e51c028d5ff2ed6c

trove/common/api.py

@@ -81,6 +81,10 @@ def _instance_router(self, mapper):
                        controller=instance_resource,
                        action="update",
                        conditions={'method': ['PUT']})
+        mapper.connect("/{tenant_id}/instances/{id}",
+                       controller=instance_resource,
+                       action="edit",
+                       conditions={'method': ['PATCH']})
         mapper.connect("/{tenant_id}/instances/{id}",
                        controller=instance_resource,
                        action="delete",

trove/common/apischema.py

@@ -219,6 +219,20 @@
             }
         }
     },
+    "edit": {
+        "name": "instance:edit",
+        "type": "object",
+        "required": ["instance"],
+        "properties": {
+            "instance": {
+                "type": "object",
+                "required": [],
+                "properties": {
+                    "slave_of": {},
+                }
+            }
+        }
+    },
     "action": {
         "resize": {
             "volume": {

trove/guestagent/api.py

@@ -335,9 +335,9 @@ def attach_replication_slave(self, snapshot, slave_config=None):
         self._cast("attach_replication_slave", snapshot=snapshot,
                    slave_config=slave_config)
 
-    def detach_replication_slave(self):
-        LOG.debug("Detaching slave %s from its master.", self.id)
-        self._call("detach_replication_slave", AGENT_HIGH_TIMEOUT)
+    def detach_replica(self):
+        LOG.debug("Detaching replica %s from its replication source.", self.id)
+        self._call("detach_replica", AGENT_HIGH_TIMEOUT)
 
     def demote_replication_master(self):
         LOG.debug("Demoting instance %s to non-master.", self.id)

trove/guestagent/datastore/cassandra/manager.py

@@ -200,10 +200,9 @@ def attach_replication_slave(self, context, snapshot, slave_config):
         raise exception.DatastoreOperationNotSupported(
             operation='attach_replication_slave', datastore=MANAGER)
 
-    def detach_replication_slave(self, context):
-        LOG.debug("Detaching replication slave.")
+    def detach_replica(self, context):
         raise exception.DatastoreOperationNotSupported(
-            operation='detach_replication_slave', datastore=MANAGER)
+            operation='detach_replica', datastore=MANAGER)
 
     def demote_replication_master(self, context):
         LOG.debug("Demoting replication master.")

trove/guestagent/datastore/couchbase/manager.py

@@ -223,10 +223,9 @@ def attach_replication_slave(self, context, snapshot, slave_config):
         raise exception.DatastoreOperationNotSupported(
             operation='attach_replication_slave', datastore=MANAGER)
 
-    def detach_replication_slave(self, context):
-        LOG.debug("Detaching replication slave.")
+    def detach_replica(self, context):
         raise exception.DatastoreOperationNotSupported(
-            operation='detach_replication_slave', datastore=MANAGER)
+            operation='detach_replica', datastore=MANAGER)
 
     def demote_replication_master(self, context):
         LOG.debug("Demoting replication slave.")

trove/guestagent/datastore/mongodb/manager.py

@@ -190,9 +190,9 @@ def attach_replication_slave(self, context, snapshot, slave_config):
         raise exception.DatastoreOperationNotSupported(
             operation='attach_replication_slave', datastore=MANAGER)
 
-    def detach_replication_slave(self, context):
+    def detach_replica(self, context):
         raise exception.DatastoreOperationNotSupported(
-            operation='detach_replication_slave', datastore=MANAGER)
+            operation='detach_replica', datastore=MANAGER)
 
     def demote_replication_master(self, context):
         raise exception.DatastoreOperationNotSupported(

trove/guestagent/datastore/mysql/manager.py

@@ -269,8 +269,8 @@ def attach_replication_slave(self, context, snapshot, slave_config):
             app.status.set_status(rd_instance.ServiceStatuses.FAILED)
             raise
 
-    def detach_replication_slave(self, context):
-        LOG.debug("Detaching replication snapshot.")
+    def detach_replica(self, context):
+        LOG.debug("Detaching replica.")
         app = MySqlApp(MySqlAppStatus.get())
         replication = REPLICATION_STRATEGY_CLASS(context)
         replication.detach_slave(app)

trove/guestagent/datastore/redis/manager.py

@@ -222,9 +222,9 @@ def attach_replication_slave(self, context, snapshot, slave_config):
         raise exception.DatastoreOperationNotSupported(
             operation='attach_replication_slave', datastore=MANAGER)
 
-    def detach_replication_slave(self, context):
+    def detach_replica(self, context):
         raise exception.DatastoreOperationNotSupported(
-            operation='detach_replication_slave', datastore=MANAGER)
+            operation='detach_replica', datastore=MANAGER)
 
     def demote_replication_master(self, context):
         raise exception.DatastoreOperationNotSupported(

trove/instance/models.py

@@ -824,6 +824,15 @@ def restart(self):
         self.update_db(task_status=InstanceTasks.REBOOTING)
         task_api.API(self.context).restart(self.id)
 
+    def detach_replica(self):
+        self.validate_can_perform_action()
+        LOG.info(_("Detaching instance %s from its replication source.")
+                 % self.id)
+        if not self.slave_of_id:
+            raise exception.BadRequest(_("Instance %s is not a replica.")
+                                       % self.id)
+        task_api.API(self.context).detach_replica(self.id)
+
     def migrate(self, host=None):
         self.validate_can_perform_action()
         LOG.info(_("Migrating instance id = %(instance_id)s "

trove/instance/service.py

@@ -75,7 +75,7 @@ def action(self, req, body, tenant_id, id):
         _actions = {
             'restart': self._action_restart,
             'resize': self._action_resize,
-            'reset_password': self._action_reset_password
+            'reset_password': self._action_reset_password,
         }
         selected_action = None
         action_name = None
@@ -261,6 +261,23 @@ def update(self, req, id, body, tenant_id):
             instance.unassign_configuration()
         return wsgi.Result(None, 202)
 
+    def edit(self, req, id, body, tenant_id):
+        """
+        Updates the instance to set or unset one or more attributes.
+        """
+        LOG.info(_("Editing instance for tenant id %s.") % tenant_id)
+        LOG.debug(logging.mask_password("req: %s"), req)
+        LOG.debug(logging.mask_password("body: %s"), body)
+        context = req.environ[wsgi.CONTEXT_KEY]
+
+        instance = models.Instance.load(context, id)
+
+        if 'slave_of' in body['instance']:
+            LOG.debug("Detaching replica from source.")
+            instance.detach_replica()
+
+        return wsgi.Result(None, 202)
+
     def configuration(self, req, tenant_id, id):
         """
         Returns the default configuration template applied to the instance.

trove/taskmanager/api.py

@@ -87,6 +87,11 @@ def restart(self, instance_id):
         self.cast(self.context,
                   self.make_msg("restart", instance_id=instance_id))
 
+    def detach_replica(self, instance_id):
+        LOG.debug("Making async call to detach replica: %s" % instance_id)
+        self.cast(self.context,
+                  self.make_msg("detach_replica", instance_id=instance_id))
+
     def migrate(self, instance_id, host):
         LOG.debug("Making async call to migrate instance: %s" % instance_id)
         self.cast(self.context,

trove/taskmanager/manager.py

@@ -57,6 +57,10 @@ def restart(self, context, instance_id):
         instance_tasks = models.BuiltInstanceTasks.load(context, instance_id)
         instance_tasks.restart()
 
+    def detach_replica(self, context, instance_id):
+        instance_tasks = models.BuiltInstanceTasks.load(context, instance_id)
+        instance_tasks.detach_replica()
+
     def migrate(self, context, instance_id, host):
         instance_tasks = models.BuiltInstanceTasks.load(context, instance_id)
         instance_tasks.migrate(host)

trove/taskmanager/models.py

@@ -880,6 +880,14 @@ def _get_replication_snapshot():
         return run_with_quotas(self.context.tenant, {'backups': 1},
                                _get_replication_snapshot)
 
+    def detach_replica(self):
+        LOG.debug("Calling detach_replica on %s" % self.id)
+        try:
+            self.guest.detach_replica()
+            self.update_db(slave_of_id=None)
+        except (GuestError, GuestTimeout):
+            LOG.exception(_("Failed to detach replica %s.") % self.id)
+
     def reboot(self):
         try:
             LOG.debug("Stopping datastore on instance %s." % self.id)

trove/tests/api/replication.py

@@ -17,6 +17,7 @@
 from proboscis.asserts import assert_raises
 from proboscis.asserts import assert_true
 from proboscis.decorators import time_out
+from proboscis import SkipTest
 from trove.common.utils import generate_uuid
 from trove.common.utils import poll_until
 from trove.tests.api.instances import CheckInstance
@@ -41,6 +42,19 @@ def __init__(self):
 existing_db_on_master = generate_uuid()
 
 
+def slave_is_running(running=True):
+
+    def check_slave_is_running():
+        server = create_server_connection(slave_instance.id)
+        cmd = ("mysqladmin extended-status "
+               "| awk '/Slave_running/{print $4}'")
+        stdout, stderr = server.execute(cmd)
+        expected = "ON" if running else "OFF"
+        return stdout.rstrip() == expected
+
+    return check_slave_is_running
+
+
 @test(depends_on_classes=[WaitForGuestInstallationToFinish],
       groups=[GROUP])
 class CreateReplicationSlave(object):
@@ -99,15 +113,7 @@ def find_database():
     @test
     @time_out(5 * 60)
     def test_correctly_started_replication(self):
-
-        def slave_is_running():
-            server = create_server_connection(slave_instance.id)
-            cmd = ("mysqladmin extended-status "
-                   "| awk '/Slave_running/{print $4}'")
-            stdout, stderr = server.execute(cmd)
-            return stdout == "ON\n"
-
-        poll_until(slave_is_running)
+        poll_until(slave_is_running())
 
     @test(depends_on=[test_correctly_started_replication])
     def test_create_db_on_master(self):
@@ -154,6 +160,24 @@ def test_get_master_instance(self):
 @test(groups=[GROUP],
       depends_on=[WaitForCreateSlaveToFinish],
       runs_after=[VerifySlave])
+class DetachReplica(object):
+
+    @test
+    @time_out(5 * 60)
+    def test_detach_replica(self):
+        if CONFIG.fake_mode:
+            raise SkipTest("Detach replica not supported in fake mode")
+
+        instance_info.dbaas.instances.edit(slave_instance.id,
+                                           detach_replica_source=True)
+        assert_equal(202, instance_info.dbaas.last_http_code)
+
+        poll_until(slave_is_running(False))
+
+
+@test(groups=[GROUP],
+      depends_on=[WaitForCreateSlaveToFinish],
+      runs_after=[DetachReplica])
 class DeleteSlaveInstance(object):
 
     @test

trove/tests/unittests/guestagent/test_api.py

@@ -298,11 +298,11 @@ def test_attach_replication_slave(self):
         # verify
         self._verify_rpc_cast(exp_msg, rpc.cast)
 
-    def test_detach_replication_slave(self):
+    def test_detach_replica(self):
         rpc.call = mock.Mock()
-        exp_msg = RpcMsgMatcher('detach_replication_slave')
+        exp_msg = RpcMsgMatcher('detach_replica')
         # execute
-        self.api.detach_replication_slave()
+        self.api.detach_replica()
         # verify
         self._verify_rpc_call(exp_msg, rpc.call)
 

trove/tests/unittests/guestagent/test_mysql_manager.py

@@ -334,7 +334,7 @@ def test_attach_replication_slave_invalid(self):
         # assertions
         self.assertEqual(mock_replication.enable_as_slave.call_count, 0)
 
-    def test_detach_replication_slave(self):
+    def test_detach_replica(self):
         mock_status = MagicMock()
         dbaas.MySqlAppStatus.get = MagicMock(return_value=mock_status)
 
@@ -343,7 +343,7 @@ def test_detach_replication_slave(self):
         self.mock_rs_class.return_value = mock_replication
 
         # entry point
-        self.manager.detach_replication_slave(self.context)
+        self.manager.detach_replica(self.context)
         # assertions
         self.assertEqual(mock_replication.detach_slave.call_count, 1)