mqtt client

The mqtt client binding encodes the MQTT protocol to the outbound network stream.

mqtt_client:
  type: mqtt
  kind: client
  exit: mqtt_client_tcp

Configuration (* required)

options

object

The client specific options.

options:
  authorization:
    my_jwt_guard:
      credentials:
        connect:
          username: Bearer {credentials}
  versions:
    - v5
    - v3.1.1

options.server

string

Upstream MQTT broker URI. When set, its host and port are forwarded to the exit binding as proxy protocol destination info, overriding the destination the exit binding would otherwise use on its own.

options.authorization

object as map of named object properties

Authorization by a named guard.

authorization:
  my_jwt_guard:
    credentials:
      connect:
        username: Bearer {credentials}

authorization.credentials*

object

Defines how to extract credentials from the MQTT connect packet.

credentials.connect*

object

MQTT connect packet properties

connect.username

string

Extract credentials from the MQTT connect packet username property with {credentials}, e.g. "Bearer {credentials}".

connect.password

string

Extract credentials from the MQTT connect packet password property with {credentials}, e.g. "Bearer {credentials}".

routes

array of object

Conditional mqtt specific routes. At least one of routes or the top-level exit is required.

routes[].guarded

object as map of named array of string

List of roles required by each named guard to authorize this route.

routes:
  - guarded:
      my_guard:
        - read:items

routes[].when

array of object

List of conditions (any match) to match this route. Read more: When a route matches

routes:
  - when:
      - session:
          - client-id: "*"
      - publish:
          - topic: command/one
          - topic: command/two
      - subscribe:
          - topic: reply

when[].session

array of object

Array of mqtt session properties

session[].client-id

string

An MQTT client identifier, allowing the usage of wildcards.

when[].publish

array of object

Array of MQTT topic configs for publish capability.

publish[].topic

string | Pattern: ^(\\/?([\\w{}\\.-]*|\\+)(\\/((?![-_])[\\w{}\\.-]*|\\+))*(\\/#)?|#|\\/|\\$SYS(\\/((?![-_])[\\w{}\\.-]*|\\+))*(\\/#)?)$

The MQTT topic to match on that supports standard MQTT wildcards /+/, /#.

Also, supports embedded parameters (e.g., {id}) for dynamic topic matching.

publish[].params

object as map of named string properties | Pattern: ^[a-zA-Z0-9{}\\[\\]\\.\\$']*$

Enforce validation of topic embedded parameters.

publish:
  - topic: device/{id}
    params:
      id: ${guarded['jwt'].identity}

Supports dynamic parameter substitution using the following pattern:

• ${guarded['jwt'].identity} – Substitutes a guarded identity value.

when[].subscribe

array of object

Array of MQTT topic configs for subscribe capability.

subscribe[].topic

string | Pattern: ^(\\/?([\\w{}\\.-]*|\\+)(\\/((?![-_])[\\w{}\\.-]*|\\+))*(\\/#)?|#|\\/|\\$SYS(\\/((?![-_])[\\w{}\\.-]*|\\+))*(\\/#)?)$

The MQTT topic to match on that supports standard MQTT wildcards /+/, /#.

Also, supports embedded parameters (e.g., {id}) for dynamic topic matching.

subscribe[].params

object as map of named string properties | Pattern: ^[a-zA-Z0-9{}\\[\\]\\.\\$']*$

Enforce validation of topic embedded parameters.

subscribe:
  - topic: device/{id}
    params:
      id: ${guarded['jwt'].identity}

Supports dynamic parameter substitution using the following pattern:

• ${guarded['jwt'].identity} – Substitutes a guarded identity value.

routes[].exit

string

Next binding when following this route.

routes:
  - when:
    ...
    exit: mqtt_kafka_proxy

exit

string

Default exit binding when no conditional routes are viable.

exit: echo_server

telemetry

object

Defines the desired telemetry for the binding.

telemetry.metrics

array

Telemetry metrics to track

telemetry:
  metrics:
    - stream.*

telemetry.attributes

object as map of named string properties

Telemetry attributes to add to the binding metrics.