Crate rants

An async NATS client library for the Rust programming language.

Note: Currently, rants requires a nightly version of the rust compiler due to its use of async/await syntax, but it should work on stable soon!

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.

Example

use futures::stream::StreamExt;
use rants::Client;
use tokio::runtime::Runtime;

let main_future = async {
   // 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;
};

let runtime = Runtime::new().expect("to create Runtime");
runtime.spawn(main_future);
runtime.shutdown_on_idle();

Modules

error

nats Error and Result

Structs

Address	An address used to connect to a NATS server
Client	The entry point to the NATS client protocol
ClientRef	A type for returning a reference to data behind Client's internal mutex
ClientRefMut	A type for returning a mutable reference to data behind Client's internal mutex
Connect	The CONNECT message sent by the client
Info	The INFO message sent by the server
MpscReceiver	Receive values from the associated Sender.
Msg	The MSG message sent by the server
Subject	A subject to publish or subscribe to
Subscription	A subscription to receive messages from a particular Subject
WatchReceiver	Receives values from the associated Sender.

Enums

Authorization	The methods of client authorization set in the Connect message
ClientState	Client states
ProtocolError	The -ERR messages sent from the server

Functions

generate_delay_generator

Generate a Client's delay_generator_mut

Type Definitions

DelayGenerator	The type of a Client's delay_generator_mut
Sid	The type used for subscription IDs