mqtt

title: "mqtt" date: 2019-11-17T12:24:10+02:00 draft: false

mqtt

Name

mqtt - Publish messages to an MQTT enabled server

Description

The mqtt plugin can publish messages about IP addresses and client requests to an MQTT server. Multiple configuration are supported and may refer to other ones for connection information. See the examples below for more information.

Syntax

mqtt [CONDITION] {
    [name/use CONFIG_NAME]
    [broker BROKER...]
    [user USERNAME]
    [password PASSWORD]
    [clean-session]
    [qos QOS]
    
    [topic TITLE]
    [payload MESSAGE]
}

• CONFIG_NAME is the name of the MQTT configuration. If specified with use the connection information of a MQTT block with the same name will be used.
• CONDITION is the condition that must match to publish to MQTT. If the condition is omitted, a message will be published for each DHCP message.
• BROKER is or more MQTT server URLs in the format of scheme://address:port. Supported protocols are tcp://, tls://, ws:// and wss://
• USER optionally configures the username required for authentication
• PASSWORD optionally configures the username required for authentication
• clean-session forces a clean-session for the client
• QOS specifies the Quality-of-Service byte to use when publishing. It should be a number between 0 and 2
• TOPIC is the topic use to publish the message. All replacement keys are supported.
• PAYLOAD is the the actual MQTT message payload. All replacement keys are supported.

Examples

This example will publish two notifications for each client that requests a new IP address to different topics:

mqtt msgtype == 'REQUEST' and clientip != '' {
    name default
    broker tcp://localhost:1883
    user mqtt-user-name
    password very-secure-password
    
    topic /dhcp/hwaddr/{hwaddr}
    payload {clientip}
}

# The following block uses escaping to construct a JSON message
# and uses the same connection information from above
mqtt msgtype == 'REQUEST' {
    use default

    topic /dhcp/requested-ip/{clientip}
    payload "\{\"clientIP\": \"{clientip}\"\}"
}