mqtt-debugger

Simple debug util for MQTT client traffic.

Usage

mqtt-debugger [options] [topicFilter] [propFilter] [valueFilter]

The command subscribes to the broker and prints only messages matching your filters.

CLI arguments

Options

| Option | Default | Description | | --- | --- | --- | | -h <host> | localhost | MQTT broker host | | -p <port> | 1883 | MQTT broker port | | -a <username:password> | admin:password | MQTT credentials in username:password format |

Positional arguments

| Argument | Default | Description | | --- | --- | --- | | topicFilter | # | Case-insensitive regex matched against topic names | | propFilter | '' | Case-insensitive regex matched against JSON property names | | valueFilter | '' | Case-insensitive regex matched against matched property values |

Notes:

• Filters are interpreted as JavaScript regular expressions.
• Message payloads are parsed as JSON.

Usage examples

Listen to everything on localhost:

npx @kcarbone/mqtt-debugger

Connect to a remote broker with auth:

npx @kcarbone/mqtt-debugger -h broker.example.com -p 1883 -a myuser:mypassword

Show only topics containing sensor:

npx @kcarbone/mqtt-debugger sensor

Show only temperature properties from topics matching devices/:

npx @kcarbone/mqtt-debugger 'devices/' 'temperature'

Show only status values matching error|fail from topics matching devices/:

npx @kcarbone/mqtt-debugger 'devices/' 'status' 'error|fail'