[ARTEMIS-3781] Send PUBREC on duplicate PUBLISH for MQTT QoS 2

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.22.0
• Assignee: Justin Bertram
• Reporter: Justin Bertram
• Created: 19/Apr/22 17:46
• Updated: 28/Apr/22 15:16
• Resolved: 20/Apr/22 16:59

Description

The MQTT 5 (and 3.1.1) specification states:

Until it has received the corresponding PUBREL packet, the receiver MUST acknowledge any subsequent PUBLISH packet with the same Packet Identifier by sending a PUBREC. It MUST NOT cause duplicate messages to be delivered to any onward recipients in this case [MQTT-4.3.3-10].

The broker prevents a duplicate message, but it doesn't response with a PUBREC.

Issue Links

• links to: GitHub Pull Request #4032