HiveMQ Mqtt Message Log Extension

Prerequisites

• HiveMQ Enterprise Edition (EE) 4.2.0 or later

• HiveMQ Community Edition (CE) 2020.1 or later

Purpose

The HiveMQ MQTT Message Log Extension is a very useful HiveMQ Extension for debugging and development purposes. It provides the possibility to follow up on any clients communicating with the broker on the terminal.

The extension logs the following events:

Event	Config Property	Minimum Version
A client connects to HiveMQ	client-connect	4.2 EE or 2020.1 CE
A client disconnects from HiveMQ	client-disconnect	4.2 EE or 2020.1 CE
A client sends a publish message	publish-received	4.2 EE or 2020.1 CE
A client sends a subscribe message	subscribe-received	4.2 EE or 2020.1 CE
HiveMQ sends a publish message to a client	publish-send	4.2 EE or 2020.1 CE
A client sends a unsubscribe message	unsubscribe-received	4.3 EE or 2020.1 CE
A client send a ping request	ping-request-received	4.3 EE or 2020.1 CE
A client completes a received Qos1 publish with a puback message	puback-received	4.3 EE or 2020.1 CE
A client acknowledges the reception of a Qos2 publish with a pubrec message	pubrec-received	4.3 EE or 2020.1 CE
A client completes a sent Qos2 publish with a pubrel message	pubrel-received	4.3 EE or 2020.1 CE
A client completes a received Qos2 publish with a pubcomp message	pubcomp-received	4.3 EE or 2020.1 CE
HiveMQ sends a connack message to a client	connack-send	4.3 EE or 2020.1 CE
HiveMQ disconnects a client with a disconnect message	client-disconnect	4.3 EE or 2020.1 CE
HiveMQ sends a suback message to a client	suback-send	4.3 EE or 2020.1 CE
HiveMQ sends a unsuback message to a client	unsuback-send	4.3 EE or 2020.1 CE
HiveMQ sends a ping response to a client	ping-response-send	4.3 EE or 2020.1 CE
HiveMQ completes a received Qos1 publish with a puback message	puback-send	4.3 EE or 2020.1 CE
HiveMQ acknowledges the reception of a Qos2 publish with a pubrec message	pubrec-send	4.3 EE or 2020.1 CE
HiveMQ completes a sent Qos2 publish with a pubrel message	pubrel-send	4.3 EE or 2020.1 CE
HiveMQ completes a received Qos2 publish with a pubcomp message	pubcomp-send	4.3 EE or 2020.1 CE

Installation

• Download the extension from the HiveMQ Marketplace.

• Copy the content of the zip file to the extensions folder of your HiveMQ nodes.

• Modify the mqttMessageLog.properties file for your needs.

Configuration

By default, all MQTT events are logged. It is possible to opt out of specific log event types by adding a mqttMessageLog.properties files to your <HIVEMQ_HOME>/hivemq-mqtt-message-log-extension folder. There is an example file available which removes the logging of publish messages. Just rename it to mqttMessageLog.properties.

The events log only important information, if it is required that MQTT messages are logging all information available the verbose property can be set to true. You can see the difference of a normal log versus a verbose log in the examples.

Caution

use verbose=true very carefully as it will flood your log immediately.

Missing entries default to true. verbose defaults to false.

First Steps

Connect with an MQTT client of your choice. You should see a log message with its client identifier, MQTT version, clean start flag and session expiry interval.

Examples

Verbose CONNECT message

"17:26:23.602 INFO - Received CONNECT from client 'clientid': Protocol version: 'V_5', Clean Start: 'false',
Session Expiry Interval: '10000', Keep Alive: '20000', Maximum Packet Size: '40000',
Receive Maximum: '30000', Topic Alias Maximum: '50000', Request Problem Information: 'true',
Request Response Information: 'false',  Username: 'the username', Password: 'the password',
Auth Method: 'auth method', Auth Data (Base64): 'YXV0aCBkYXRh',
User Properties: [Name: 'name0', Value: 'value0'], [Name: 'name1', Value: 'value1'],
Will: { Topic: 'willtopic', Payload: 'payload', QoS: '1', Retained: 'false', Message Expiry Interval: '1234',
Duplicate Delivery: 'false', Correlation Data: 'data', Response Topic: 'response topic',
Content Type: 'content type', Payload Format Indicator: 'UTF_8', Subscription Identifiers: '[1, 2, 3, 4]',
User Properties: [Name: 'name0', Value: 'value0'], [Name: 'name1', Value: 'value1'],
[Name: 'name2', Value: 'value2'], Will Delay: '100' }"

Basic CONNECT message

"17:26:23.602 INFO - Received CONNECT from client 'clientid': Protocol version: 'V_5', Clean Start: 'false', Session Expiry Interval: '10000'"

Need Help?

If you encounter any problems, we are happy to help. The best place to get in contact is our support.

Contributing

If you want to contribute to HiveMQ Mqtt Message Log Extension, see the contribution guidelines.

License

HiveMQ Mqtt Message Log Extension is licensed under the APACHE LICENSE, VERSION 2.0. A copy of the license can be found here.