Struct async_nats::jetstream::message::Message

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pub struct Message {
    pub message: Message,
    pub context: Context,
}

Fields

message: Messagecontext: Context

Implementations

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impl Message

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pub async fn ack(&self) -> Result<(), Error>

Acknowledges a message delivery by sending +ACK to the server.

If AckPolicy is set to All or Explicit, messages has to be acked. Otherwise redeliveries will occur and Consumer will not be able to advance.

Examples

use futures::StreamExt;
use async_nats::jetstream::consumer::PullConsumer;
let client = async_nats::connect("localhost:4222").await?;
let jetstream = async_nats::jetstream::new(client);

let consumer: PullConsumer = jetstream
    .get_stream("events").await?
    .get_consumer("pull").await?;

let mut messages = consumer.fetch().max_messages(100).messages().await?;

while let Some(message) = messages.next().await {
    message?.ack().await?;
}

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pub async fn ack_with(&self, kind: AckKind) -> Result<(), Error>

Acknowledges a message delivery by sending a choosen AckKind variant to the server.

Examples

use futures::StreamExt;
use async_nats::jetstream::AckKind;
use async_nats::jetstream::consumer::PullConsumer;
let client = async_nats::connect("localhost:4222").await?;
let jetstream = async_nats::jetstream::new(client);

let consumer: PullConsumer = jetstream
    .get_stream("events").await?
    .get_consumer("pull").await?;

let mut messages = consumer.fetch().max_messages(100).messages().await?;

while let Some(message) = messages.next().await {
    message?.ack_with(AckKind::Nak).await?;
}

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pub async fn double_ack(&self) -> Result<(), Error>

Acknowledges a message delivery by sending +ACK to the server and awaits for confirmation for the server that it received the message. Useful if user wants to ensure exactly once semantics.

If AckPolicy is set to All or Explicit, messages has to be acked. Otherwise redeliveries will occur and Consumer will not be able to advance.

Examples

use futures::StreamExt;
let client = async_nats::connect("localhost:4222").await?;
let jetstream = async_nats::jetstream::new(client);

let consumer = jetstream
    .get_stream("events").await?
    .get_consumer("pull").await?;

let mut messages = consumer.fetch().max_messages(100).messages().await?;

while let Some(message) = messages.next().await {
    message?.double_ack().await?;
}