Welcome to the LLM Litmus Test

To create a route in Axum that streams a response, you can use the axum::response::Stream type. This allows you to return a stream of data as the HTTP response. Here's a basic example of how to do this:

1use axum::{
2    routing::get,
3    Router,
4    response::IntoResponse,
5};
6use futures::stream::{self, StreamExt};
7use http::StatusCode;
8use hyper::Body;
9use std::net::SocketAddr;
10
11async fn stream_response() -> impl IntoResponse {
12    let stream = stream::iter(vec!["Hello", " ", "world!"])
13        .map(|chunk| Ok::<_, hyper::Error>(chunk.into()));
14    (StatusCode::OK, Body::wrap_stream(stream))
15}
16
17#[tokio::main]
18async fn main() {
19    // build our application with a single route
20    let app = Router::new().route("/", get(stream_response));
21
22    // run our app with hyper
23    let addr = SocketAddr::from(([127, 0, 0, 1], 3000));
24    println!("listening on {}", addr);
25    axum::Server::bind(&addr)
26        .serve(app.into_make_service())
27        .await
28        .unwrap();
29}

In this example, we use futures::stream::iter to create a simple stream from a vector of &str. Each chunk of the stream is then converted to a Result<_, hyper::Error>, which is required by Body::wrap_stream. This stream is then used to create a Body that is returned as part of the response.

This is a basic example to demonstrate streaming responses. Depending on your use case, you might be streaming data from a file, a database, or another source. The key part is to convert your data into a stream and then use Body::wrap_stream to create a response body that Axum can send back to the client.

To create a route that streams a response in Axum, you can use the axum::body::StreamBody type. Here's an example of how to create a route that streams a response:

1use axum::{
2    body::StreamBody,
3    response::IntoResponse,
4    routing::get,
5    Router,
6};
7use futures::stream::{self, Stream};
8use std::time::Duration;
9
10async fn stream() -> impl IntoResponse {
11    let stream = stream::repeat(b"data: Hello, world!\n\n")
12        .map(Ok)
13        .throttle(Duration::from_secs(1));
14
15    StreamBody::new(stream)
16}
17
18let app = Router::new().route("/stream", get(stream));

In this example:

1. We define an async function called stream that returns an impl IntoResponse.

2. Inside the stream function, we create a Stream using stream::repeat that repeatedly yields the bytes b"data: Hello, world!\n\n". This creates an infinite stream of the same data.

3. We use map(Ok) to wrap each item in the stream with Ok to convert it into a Result.

4. We use throttle to limit the rate at which items are emitted from the stream. In this case, we throttle the stream to emit items every 1 second using Duration::from_secs(1).

5. We create a StreamBody using StreamBody::new and pass the stream to it. StreamBody implements IntoResponse, so it can be returned directly from the handler.

6. Finally, we create a route using get(stream) and mount it on the /stream path using Router::new().route("/stream", ...).

When a client makes a request to /stream, the stream handler will be invoked, and the response will be streamed back to the client. The client will receive the data "data: Hello, world!\n\n" every 1 second indefinitely.

You can customize the stream by generating your own data and adjusting the throttling duration as needed.

Note that streaming responses are useful for scenarios like server-sent events (SSE), where you want to continuously send data to the client over a long-lived connection.