MigratoryDataMessage::QoS
The quality of service (QoS) levels for MigratoryData messaging.
Public Attributes
Name | |
---|---|
STANDARD The [QoS.STANDARD]() should be used for noncritical messages which will not be included in the cache of the MigratoryData cluster. |
|
GUARANTEED The [QoS.GUARANTEED]() should be used for critical messages which will be included in the cache of the MigratoryData cluster. |
Public Attributes Documentation
variable STANDARD
STANDARD;
The [QoS.STANDARD]()
should be used for noncritical messages which will not be included in the cache of the MigratoryData cluster.
In this way, after a connection recovery, a client will not receive as part of the recovery process the messages with [QoS.STANDARD](/docs/client-api/python/classes/interfacemigratorydatamessage_1_1qos/#variable-standard)
.
Note: This QoS level corresponds to the at-most-once
delivery semantics.
variable GUARANTEED
GUARANTEED;
The [QoS.GUARANTEED]()
should be used for critical messages which will be included in the cache of the MigratoryData cluster.
In this way, after a connection recovery, a client will receive as part of the recovery process the messages with [QoS.GUARANTEED](/docs/client-api/python/classes/interfacemigratorydatamessage_1_1qos/#variable-guaranteed)
.
Note: This QoS level corresponds to the at-least-once
delivery semantics. Also, it might correspond to the exactly-once
delivery semantics provided that subscribers are responsible for filtering out duplicate receptions, if it at all matters for the application. Typically, a small buffer containing the identifiers of recently-received messages is sufficient for this task.