gemqtt/publisher

Module for publishing messages to an MQTT server.

Example usage:

let msg_payload = bit_array.from_string("test payload")

let assert Ok(_) =
  publisher.new(client, "my/topic")
  |> publisher.set_qos(gemqtt.AtLeastOnce)
  |> publisher.publish(msg_payload)

Types

PublishOption

</>

pub type PublishOption {
  Retain(Bool)
  Qos(gemqtt.Qos)
}

Constructors

```
Retain(Bool)
```
```
Qos(gemqtt.Qos)
```

Publisher

</>

Publisher holds the configuration for publishing to a particular topic. Create it with the new function.

pub type Publisher {
  Publisher(
    client: Client,
    topic: String,
    options: List(PublishOption),
    properties: Properties,
  )
}

Constructors

Publisher(
  client: Client,
  topic: String,
  options: List(PublishOption),
  properties: Properties,
)

Functions

new

</>

pub fn new(client: Client, topic: String) -> Publisher

Creates a new publisher for the specified topic.

publish

</>

pub fn publish(
  publisher: Publisher,
  payload: BitArray,
) -> Result(Option(Int), Error)

Sends a PUBLISH packet to the server.

Upon success, will returns Ok(Some(packet ID)) if QoS is AtLeastOnce or ExactlyOnce, otherwise Ok(None).

set_qos

</>

pub fn set_qos(publisher: Publisher, qos: Qos) -> Publisher

Sets the QoS level for published messages; defaults to AtMostOnce.

set_retain

</>

pub fn set_retain(
  publisher: Publisher,
  retain: Bool,
) -> Publisher

Indicates to the server whether the most recently published message should be retained for future subscribers as a last known good message on this topic. Defaults to false.