[ARTEMIS-4365] MQTT retain flag not set correctly

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.29.0
• Fix Version/s: 2.30.0
• Assignee: Justin Bertram
• Reporter: Justin Bertram
• Created: 17/Jul/23 20:10
• Updated: 21/Jul/23 13:31
• Resolved: 19/Jul/23 11:50

Description

The retain flag set on MQTT messages dispatched to clients is incorrect in certain circumstances. This is demonstrated by using the test command from the MQTT CLI tool, e.g.:

$ mqtt test --all
MQTT 3: OK
    - Maximum topic length: 65535 bytes
    - QoS 0: Received 100000/100000 publishes in 4847.01ms
    - QoS 1: Received 100000/100000 publishes in 27413.45ms
    - QoS 2: Received 100000/100000 publishes in 49551.40ms
    - Retain: OK
    - Wildcard subscriptions: OK
    - Shared subscriptions: OK
    - Payload size: >= 100000 bytes
    - Maximum client id length: 65535 bytes
    - Unsupported Ascii Chars: ALL SUPPORTED
MQTT 5: OK
    - Connect restrictions: 
        > Retain: OK
        > Wildcard subscriptions: OK
        > Shared subscriptions: OK
        > Subscription identifiers: OK
        > Maximum QoS: 2
        > Receive maximum: 65535
        > Maximum packet size: 268435455 bytes
        > Topic alias maximum: 65535
        > Session expiry interval: Client-based
        > Server keep alive: Client-based
    - Maximum topic length: 65535 bytes
    - QoS 0: Received 100000/100000 publishes in 706.21ms
    - QoS 1: Received 100000/100000 publishes in 805.38ms
    - QoS 2: Received 100000/100000 publishes in 972.98ms
    - Retain: TIME_OUT
    - Wildcard subscriptions: OK
    - Shared subscriptions: OK
    - Payload size: >= 100000 bytes
    - Maximum client id length: 65535 bytes
    - Unsupported Ascii Chars: ALL SUPPORTED

Notice the result of TIME_OUT when testing retain functionality for MQTT 5.

Issue Links

• links to: GitHub Pull Request #4556