Request-Reply Pattern

Request-Reply is a common pattern in modern distributed systems. A request is sent, and the application either waits on the response with a certain timeout, or receives a response asynchronously.

Create a service that will be responding to requests:

await using var nats = new NatsConnection();

await foreach (var msg in nats.SubscribeAsync<int>("math.double").WithCancellation(cts.Token))
{
    Console.WriteLine($"Received request: {msg.Data}");

    await msg.ReplyAsync($"Answer is: {2 * msg.Data}");
}

Reply to a request is asynchronously received using an inbox subscription behind the scenes:

await using var nats = new NatsConnection();

var reply = await nats.RequestAsync<int, string>("math.double", 2);

Console.WriteLine($"Received reply: {reply.Data}");