Mqtt5 Test Release

<!-- .. title: MQTT 5 Test Release .. slug: mqtt5-test-release .. date: 2019-02-14 10:30:00 UTC .. tags: Releases .. category: .. link: .. description: .. type: text -->

The work on MQTT v5 support in Mosquitto has reached a point where it may be of interest to a range of people. It is not yet complete, but wider testing and feedback would be appreciated.

The source is available at mosquitto-mqtt5-test1.tar.gz and can be compiled as normal.

Supported features

• Session expiry
• Message expiry
• Reason code on all ACKs (not all reason codes are used)
• Reason string on all ACKs (no reason strings are provided by the broker however)
• Payload format and content type
• Request / response pattern
• Subscription ID
• Topic alias
• Flow control
• User properties
• Optional server feature availability
• Subscription options
• Server keep alive
• Assigned Client ID

Unsupported features

• Shared subscriptions
• Extended authentication
• Server reference
• Not all reason codes are used by the broker
• Bridges do not use MQTT v5
• On disk persistence does not include MQTT 5 property support
• The broker will not create topic aliases