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mqtt.publish()

mqtt.publish(topic, message) → number

Publishes a message to an MQTT topic.

Publishes message to topic. Message data can be text or binary: convert objects with string(obj) first, and pack numeric arrays to binary with bin.fromArray().

Arguments

NameTypeRequiredDefaultDescription
topic string yes Topic to publish to, e.g. "power_system/battery_voltage".
message string | binary yes Payload. Objects: string(obj). Numeric arrays: bin.fromArray().

Returns

number 0 on success, otherwise an error code.

Example

let ret = mqtt.publish("power_system/battery_voltage", string(14.34));
print("publish:", ret);