Network MQTT Client

MQTT client module, to communicate with a MQTT server. The MQTT protocol can be used to retrieve values of sensors on a distant server. See MQTT for more info.

Settings

broker host

Address of the MQTT server.

broker port

Port used for the communication with the server.

client ID

Client identifier used for the communication.

user name

User name of the client, if needed.

password

Password of the client, if needed.

connect

Try to connect the client to the server. See auto connect at startup and auto reconnect parameters bellow.

disconnect

Try to disconnect the client to the server.

connected

Sends 1 value when the client is connected to the server.

keep alive

Keep alive ensures that the connection between the broker and client is still open and that the broker and the client are aware of being connected.

auto reconnect

Determines the ability for the client to reconnect automatically on connection failure.

auto connect at startup

Connect the client to the server immediately after the module is loaded.

clean session

On connection, a client sets the "clean session" flag, which is sometimes also known as the "clean start" flag. If clean session is set to false, then the connection is treated as durable. This means that when the client disconnects, any subscriptions it has will remain and any subsequent QoS 1 or 2 messages will be stored until it connects again in the future. If clean session is true, then all subscriptions will be removed for the client when it disconnects.

trace data

Traces all incoming data's in the trace-panel.

Publishing

topic publish

Topic to publish, as a an ascii string.

payload

Payload for the topic as an ascii string, generally a json.

qoS

Quality of Service (QoS) level. It is an agreement between the sender of a message and the receiver of a message that defines the guarantee of delivery for a specific message. See QoS.

There are 3 QoS levels in MQTT:

  • At most once (0)
  • At least once (1)
  • Exactly once (2)

retain

A retained message is a normal MQTT message with the retained flag set to true. The broker stores the last retained message and the corresponding QoS for that topic. See retain.

publish

Publishes all the topics.

subscription

topics to subscribe

List of all topics to subscribe as a comma-text. ie. "dev/#","sensor/+/temperature".

clear all out

Clears all the subscriptions outputs.

receive

Sends 1 value when a topic is received.

topic out

Topic received as a string.

payload string

Payload received as a string, generally a json.

payload bytes

Payload received as an array of bytes (ascii chars).

all receives

Sends 1 value when a any of the topics is received.

all topics out

All topics received as a string.

all payload strings

All payloads received as a string, generally a json.

all payloads bytes

All payloads received as an array of bytes (ascii chars).

See also

version 6.0.240115

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