An async NATS client library for the Rust programming language.
The client aims to be an ergonomic, yet thin, wrapper over the NATS client protocol. The easiest way to learn to use the client is by reading the NATS client protocol documentation. The main entry point into the library's API is the Client
struct.
TLS support can be powered by the native-tls
crate enabled with the native-tls
feature, or TLS support can be powered by the rustls
crate enabled with the rustls-tls
feature.
use futures::stream::StreamExt;
use rants::Client;
#[tokio::main]
async fn main() {
// A NATS server must be running on `127.0.0.1:4222`
let address = "127.0.0.1:4222".parse().unwrap();
let client = Client::new(vec![address]);
// Configure the client to receive messages even if it sent the message
client.connect_mut().await.echo(true);
// Connect to the server
client.connect().await;
// Create a new subject called "test"
let subject = "test".parse().unwrap();
// Subscribe to the "test" subject
let (_, mut subscription) = client.subscribe(&subject, 1024).await.unwrap();
// Publish a message to the "test" subject
client
.publish(&subject, b"This is a message!")
.await
.unwrap();
// Read a message from the subscription
let message = subscription.next().await.unwrap();
let message = String::from_utf8(message.into_payload()).unwrap();
println!("Received '{}'", message);
// Disconnect from the server
client.disconnect().await;
}
The integration test suite requires the NATS_PATH
environment variable point to the NATS server executable:
> cargo test
The env_logger
crate is used in integration tests. To enable it and run a single test run:
> RUST_LOG=rants=trace cargo test ping_pong