Notifications in Masakari¶
Similarly to other OpenStack services Masakari emits notifications to the message bus with the Notifier class provided by oslo.messaging-doc. From the notification consumer point of view a notification consists of two parts: an envelope with a fixed structure defined by oslo.messaging and a payload defined by the service emitting the notification. The envelope format is the following:
{
"priority": <string, selected from a predefined list by the sender>,
"event_type": <string, defined by the sender>,
"timestamp": <string, the isotime of when the notification emitted>,
"publisher_id": <string, defined by the sender>,
"message_id": <uuid, generated by oslo>,
"payload": <json serialized dict, defined by the sender>
}
- oslo.messaging provides below choices of notification drivers:
Driver
Description
messaging
Send notifications using the 1.0 message format
messagingv2
Send notifications using the 2.0 message format (with a message envelope)
routing
Configurable routing notifier (by priority or event_type)
log
Publish notifications via Python logging infrastructure
test
Store notifications in memory for test verification
noop
Disable sending notifications entirely
So notifications can be completely disabled by setting the following in Masakari configuration file:
[oslo_messaging_notifications]
driver = noop
Masakari supports only Versioned notifications.
Versioned notifications¶
Masakari code uses the masakari.rpc.get_notifier call to get a configured
oslo.messaging Notifier object and it uses the oslo provided functions on the
Notifier object to emit notifications. The configuration of the returned
Notifier object depends on the parameters of the get_notifier call and the
value of the oslo.messaging configuration options driver and topics.
The versioned notification the the payload is not a free form dictionary but a
serialized oslo.versionedobjects-doc.
For example the wire format of the segment.update notification looks like
the following:
{
"event_type": "api.update.segments.start",
"timestamp": "2018-11-27 14:32:20.396940",
"payload": {
"masakari_object.name": "SegmentApiPayload",
"masakari_object.data": {
"description": null,
"fault": null,
"recovery_method": "auto",
"name": "test",
"service_type": "compute",
"id": 877,
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
}, "
"masakari_object.version": "1.0",
"masakari_object.namespace": "masakari"
},
"priority": "INFO",
"publisher_id": "masakari-api:test-virtualbox",
"message_id": "e6322900-025d-4dd6-a3a1-3e0e1e9badeb"
}
The serialized oslo versionedobject as a payload provides a version number to the consumer so the consumer can detect if the structure of the payload is changed. Masakari provides the following contract regarding the versioned notification payload:
the payload version defined by the
masakari_object.versionfield of the payload will be increased if and only if the syntax or the semantics of themasakari_object.datafield of the payload is changed.a minor version bump indicates a backward compatible change which means that only new fields are added to the payload so a well written consumer can still consume the new payload without any change.
a major version bump indicates a backward incompatible change of the payload which can mean removed fields, type change, etc in the payload.
there is an additional field ‘masakari_object.name’ for every payload besides ‘masakari_object.data’ and ‘masakari_object.version’. This field contains the name of the Masakari internal representation of the payload type. Client code should not depend on this name.
Existing versioned notifications¶
This provides the list of existing versioned notifications with sample payloads.
| Event type | Notification class | Payload class | Sample |
error.exception |
ExceptionNotification |
ExceptionPayload |
{
"event_type": "segment.create.error",
"message_id": "e5405591-1d19-4a8c-aa92-4d551165d863",
"payload": {
"masakari_object.data": {
"description": null,
"fault": {
"masakari_object.data": {
"exception": "DBError",
"exception_message": "(pymysql.err.Internal Error) (1054, u\"Unknown column 'name' in 'field list'\" ...",
"function_name": "raise_mysql_exception",
"module_name": "pymysql.err",
"traceback": "Traceback (most recent call last):\n File \"/opt/stack/masakari/masakari/ha/api.py\", line ..."
},
"masakari_object.name": "ExceptionPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"name": "testT6",
"recovery_method": "auto",
"service_type": "compute"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "ERROR",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-28 14:24:27.902437"
} |
create.host.end |
HostApiNotification |
HostApiPayload |
{
"event_type": "host.create.end",
"message_id": "e437834a-73e1-4c47-939a-83f6aca2e7ac",
"payload": {
"masakari_object.data": {
"control_attributes": "TEST",
"failover_segment": {
"masakari_object.data": {
"created_at": "2018-11-27T09:26:30Z",
"deleted": false,
"deleted_at": null,
"description": null,
"id": 877,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"updated_at": "2018-11-27T09:54:50Z",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "FailoverSegment",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"failover_segment_id": "89597691-bebd-4860-a93e-1b6e9de34b9e",
"fault": null,
"id": 70,
"name": "fake-mini",
"on_maintenance": false,
"reserved": false,
"type": "COMPUTE",
"uuid": "d6a2d900-1977-48fd-aa52-ad7a41fc068b"
},
"masakari_object.name": "HostApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:09:30.737034"
} |
create.host.start |
HostApiNotification |
HostApiPayload |
{
"event_type": "host.create.start",
"message_id": "0ed836cc-353a-40bc-b86b-d89e6632d838",
"payload": {
"masakari_object.data": {
"control_attributes": "TEST",
"failover_segment_id": "89597691-bebd-4860-a93e-1b6e9de34b9e",
"fault": null,
"name": "fake-mini",
"on_maintenance": false,
"reserved": false,
"type": "COMPUTE"
},
"masakari_object.name": "HostApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:09:30.716747"
} |
delete.host.end |
HostApiNotification |
HostApiPayload |
{
"event_type": "host.delete.end",
"message_id": "64d61bcf-c875-41c3-b795-19a076f6de96",
"payload": {
"masakari_object.data": {
"control_attributes": "TEST",
"failover_segment": {
"masakari_object.data": {
"created_at": "2018-11-27T09:26:30Z",
"deleted": false,
"deleted_at": null,
"description": null,
"id": 877,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"updated_at": "2018-11-27T09:54:50Z",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "FailoverSegment",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"failover_segment_id": "89597691-bebd-4860-a93e-1b6e9de34b9e",
"fault": null,
"name": "fake-mini",
"on_maintenance": false,
"reserved": false,
"type": "COMPUTE",
"uuid": "3d8d1751-9cab-4a48-8801-96f102200077"
},
"masakari_object.name": "HostApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:35:09.882636"
} |
delete.host.start |
HostApiNotification |
HostApiPayload |
{
"event_type": "host.delete.start",
"message_id": "b5914f94-99dd-42fa-aaf3-3cedacda6b67",
"payload": {
"masakari_object.data": {
"control_attributes": "TEST",
"failover_segment": {
"masakari_object.data": {
"created_at": "2018-11-27T09:26:30Z",
"deleted": false,
"deleted_at": null,
"description": null,
"id": 877,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"updated_at": "2018-11-27T09:54:50Z",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "FailoverSegment",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"failover_segment_id": "89597691-bebd-4860-a93e-1b6e9de34b9e",
"fault": null,
"id": 71,
"name": "fake-mini",
"on_maintenance": false,
"reserved": false,
"type": "COMPUTE",
"uuid": "3d8d1751-9cab-4a48-8801-96f102200077"
},
"masakari_object.name": "HostApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:31:47.451466"
} |
update.host.end |
HostApiNotification |
HostApiPayload |
{
"event_type": "host.update.end",
"message_id": "e7f85d49-7d02-4713-b90b-433f8e447558",
"payload": {
"masakari_object.data": {
"control_attributes": "TEST",
"failover_segment": {
"masakari_object.data": {
"created_at": "2018-11-27T09:26:30Z",
"deleted": false,
"deleted_at": null,
"description": null,
"id": 877,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"updated_at": "2018-11-27T09:54:50Z",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "FailoverSegment",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"failover_segment_id": "89597691-bebd-4860-a93e-1b6e9de34b9e",
"fault": null,
"id": 70,
"name": "fake-mini",
"on_maintenance": false,
"reserved": false,
"type": "COMPUTE",
"uuid": "d6a2d900-1977-48fd-aa52-ad7a41fc068b"
},
"masakari_object.name": "HostApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:13:25.361394"
} |
update.host.start |
HostApiNotification |
HostApiPayload |
{
"event_type": "host.update.start",
"message_id": "d1a3ae84-7f41-4884-bc3f-fa34c7cd1424",
"payload": {
"masakari_object.data": {
"control_attributes": "TEST",
"failover_segment": {
"masakari_object.data": {
"created_at": "2018-11-27T09:26:30Z",
"deleted": false,
"deleted_at": null,
"description": null,
"id": 877,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"updated_at": "2018-11-27T09:54:50Z",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "FailoverSegment",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"failover_segment_id": "89597691-bebd-4860-a93e-1b6e9de34b9e",
"fault": null,
"id": 70,
"name": "fake-mini",
"on_maintenance": false,
"reserved": false,
"type": "COMPUTE",
"uuid": "d6a2d900-1977-48fd-aa52-ad7a41fc068b"
},
"masakari_object.name": "HostApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:13:25.298007"
} |
create.notification.end |
NotificationApiNotification |
NotificationApiPayload |
{
"event_type": "notification.create.end",
"message_id": "500447b9-4797-4090-9189-b56bc3521b75",
"payload": {
"masakari_object.data": {
"fault": null,
"generated_time": "2017-06-13T15:34:55Z",
"id": 1,
"notification_uuid": "e6b1996f-7792-4a65-83c3-23f2d4721eb0",
"payload": {
"process_name": "nova-compute"
},
"source_host_uuid": "d4ffe3a4-b2a8-41f3-a2b0-bae3b06fc1a3",
"status": "new",
"type": "VM"
},
"masakari_object.name": "NotificationApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:46:25.496514"
} |
create.notification.start |
NotificationApiNotification |
NotificationApiPayload |
{
"event_type": "notification.create.start",
"message_id": "5e2e4699-0bbd-4583-b1e2-a87c458f84eb",
"payload": {
"masakari_object.data": {
"fault": null,
"generated_time": "2017-06-13T15:34:55Z",
"payload": {
"process_name": "nova-compute"
},
"source_host_uuid": "d4ffe3a4-b2a8-41f3-a2b0-bae3b06fc1a3",
"status": "new",
"type": "VM"
},
"masakari_object.name": "NotificationApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 13:46:23.060352"
} |
process.notification.end |
NotificationApiNotification |
NotificationApiPayload |
{
"event_type": "notification.process.end",
"message_id": "c081eb25-7450-4fa2-bb19-ae6d4466e14e",
"payload": {
"masakari_object.data": {
"fault": null,
"generated_time": "2017-06-13T15:34:55Z",
"id": 47,
"notification_uuid": "15505a8c-8856-4f3d-9747-55b6e899c0f5",
"payload": {
"process_name": "nova-compute"
},
"source_host_uuid": "6bfaf80d-7592-4ea8-ad12-60d45476d056",
"status": "ignored",
"type": "VM"
},
"masakari_object.name": "NotificationApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-engine:fake-mini",
"timestamp": "2018-12-20 05:26:05.075917"
} |
process.notification.error |
NotificationApiNotification |
NotificationApiPayload |
{
"event_type": "notification.process.error",
"message_id": "5f3c9705-b3fb-41f9-a4e0-4868db93178c",
"payload": {
"masakari_object.data": {
"fault": {
"masakari_object.data": {
"exception": "str",
"exception_message": "Failed to execute process recovery workflow.",
"function_name": "_handle_notification_type_process",
"module_name": "masakari.engine.manager",
"traceback": "Traceback (most recent call last):\n File \"/opt/stack/masakari/masakari/engine/manager.py\", line ..."
},
"masakari_object.name": "ExceptionPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"generated_time": "2017-06-13T15:34:55Z",
"id": 51,
"notification_uuid": "0adb94e0-8283-4702-9793-186d4ed914e8",
"payload": {
"process_name": "nova-compute"
},
"source_host_uuid": "6bfaf80d-7592-4ea8-ad12-60d45476d056",
"status": "running",
"type": "PROCESS"
},
"masakari_object.name": "NotificationApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "ERROR",
"publisher_id": "masakari-engine:fake-mini",
"timestamp": "2018-12-20 06:21:19.315761"
} |
process.notification.start |
NotificationApiNotification |
NotificationApiPayload |
{
"event_type": "notification.process.start",
"message_id": "285be756-ac29-4b78-9e2b-9756f5077012",
"payload": {
"masakari_object.data": {
"fault": null,
"generated_time": "2017-06-13T15:34:55Z",
"id": 47,
"notification_uuid": "15505a8c-8856-4f3d-9747-55b6e899c0f5",
"payload": {
"process_name": "nova-compute"
},
"source_host_uuid": "6bfaf80d-7592-4ea8-ad12-60d45476d056",
"status": "new",
"type": "VM"
},
"masakari_object.name": "NotificationApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-engine:fake-mini",
"timestamp": "2018-12-20 05:26:05.002421"
} |
create.segment.end |
SegmentApiNotification |
SegmentApiPayload |
{
"event_type": "segment.create.end",
"message_id": "b8478b31-5943-4495-8867-e8291655f660",
"payload": {
"masakari_object.data": {
"description": null,
"fault": null,
"id": 850,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"uuid": "5cce639c-da08-4e78-b615-66c88aa49d50"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-22 09:25:12.813483"
} |
create.segment.start |
SegmentApiNotification |
SegmentApiPayload |
{
"event_type": "segment.create.start",
"message_id": "e44cb15b-dcba-409e-b0e1-9ee103b9a168",
"payload": {
"masakari_object.data": {
"description": null,
"fault": null,
"name": "test",
"recovery_method": "auto",
"service_type": "compute"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-22 09:25:12.393979"
} |
delete.segment.end |
SegmentApiNotification |
SegmentApiPayload |
{
"event_type": "segment.delete.end",
"message_id": "00184d05-7a96-4021-b44e-03912a6c0b0d",
"payload": {
"masakari_object.data": {
"description": null,
"fault": null,
"name": "test2",
"recovery_method": "auto",
"service_type": "compute",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 14:36:07.457369"
} |
delete.segment.start |
SegmentApiNotification |
SegmentApiPayload |
{
"event_type": "segment.delete.start",
"message_id": "e6c32ecb-eacc-433d-ba8c-6390ea3da6d2",
"payload": {
"masakari_object.data": {
"description": null,
"fault": null,
"id": 877,
"name": "test2",
"recovery_method": "auto",
"service_type": "compute",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 14:36:07.442538"
} |
update.segment.end |
SegmentApiNotification |
SegmentApiPayload |
{
"event_type": "segment.update.end",
"message_id": "3fbe50a5-9175-4161-85f0-e502f9024657",
"payload": {
"masakari_object.data": {
"description": null,
"fault": null,
"id": 877,
"name": "test2",
"recovery_method": "auto",
"service_type": "compute",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 14:32:20.417745"
} |
update.segment.start |
SegmentApiNotification |
SegmentApiPayload |
{
"event_type": "segment.update.start",
"message_id": "e6322900-025d-4dd6-a3a1-3e0e1e9badeb",
"payload": {
"masakari_object.data": {
"description": null,
"fault": null,
"id": 877,
"name": "test",
"recovery_method": "auto",
"service_type": "compute",
"uuid": "89597691-bebd-4860-a93e-1b6e9de34b9e"
},
"masakari_object.name": "SegmentApiPayload",
"masakari_object.namespace": "masakari",
"masakari_object.version": "1.0"
},
"priority": "INFO",
"publisher_id": "masakari-api:fake-mini",
"timestamp": "2018-11-27 14:32:20.396940"
} |
