topic_subscriber

Types

Ack

Return type for topic subscriber acknowledgements.

pub type Ack

Builder

opaque </>

A builder for creating and configuring a Kafka topic subscriber.

pub opaque type Builder(callback_init_state)

Message

</>

pub type Message

Partitions

</>

Specifies which partitions to consume from.

pub type Partitions {
  Partitions(List(Int))
  All
}

Constructors

```
Partitions(List(Int))
```
Consume from specific partition numbers.
```
All
```
Consume from all available partitions.

TopicSubscriber

</>

pub type TopicSubscriber {
  TopicSubscriber(name: process.Name(Message))
}

Constructors

TopicSubscriber(name: process.Name(Message))

Values

ack

</>

pub fn ack(cb_state: cb_state) -> Ack

Acknowledges the processing of a message. Use this in your callback to confirm message receipt.

named_client

</>

pub fn named_client(
  name: process.Name(Message),
) -> TopicSubscriber

new

</>

pub fn new(
  name name: process.Name(Message),
  client client: franz.Client,
  topic topic: String,
  partitions partitions: Partitions,
  message_type message_type: message_type.MessageType,
  callback callback: fn(
    Int,
    franz.KafkaMessage,
    callback_init_state,
  ) -> Ack,
  init_callback_state init_callback_state: callback_init_state,
) -> Builder(callback_init_state)

Creates a new topic subscriber builder. The callback will be called for each message received from the topic partitions.

start

</>

pub fn start(
  builder: Builder(callback_init_state),
) -> Result(actor.Started(TopicSubscriber), actor.StartError)

Starts a new topic subscriber with the configured settings.

supervised

</>

pub fn supervised(
  builder: Builder(a),
) -> supervision.ChildSpecification(TopicSubscriber)

Creates a supervised worker for the topic subscriber. This can be used with Gleam’s OTP supervision trees to ensure the subscriber is restarted on failure.

with_commited_offset

</>

pub fn with_commited_offset(
  builder: Builder(callback_init_state),
  partition partition: Int,
  offset offset: Int,
) -> Builder(callback_init_state)

Adds a committed offset to the topic subscriber builder. CommittedOffsets are the offsets for the messages that have been successfully processed (acknowledged), not the begin-offset to start fetching from.

with_config

</>

pub fn with_config(
  builder: Builder(callback_init_state),
  consumer_config: config.Config,
) -> Builder(callback_init_state)

Adds a consumer configuration option to the topic subscriber builder. Multiple configurations can be chained together.