wasm-streams 0.3.0

Bridging between web streams and Rust streams using WebAssembly
Documentation 
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//! ## Reading a streaming fetch response
//!
//! This example makes an HTTP request using `fetch()` from `web-sys`,
//! and then consumes the response body as a Rust `Stream`.

use futures_util::StreamExt;
use wasm_bindgen::{prelude::*, JsCast};
use wasm_bindgen_futures::JsFuture;
use web_sys::{console, window, Response};

use wasm_streams::ReadableStream;

#[tokio::main(flavor = "current_thread")]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Make a fetch request
    let url = "https://rustwasm.github.io/assets/wasm-ferris.png";
    let window = window().unwrap_throw();
    let resp_value = JsFuture::from(window.fetch_with_str(url))
        .await
        .map_err(|_| "fetch failed")?;
    let resp: Response = resp_value.dyn_into().unwrap_throw();

    // Get the response's body as a JS ReadableStream
    let raw_body = resp.body().unwrap_throw();
    let body = ReadableStream::from_raw(raw_body.dyn_into().unwrap_throw());

    // Convert the JS ReadableStream to a Rust stream
    let mut stream = body.into_stream();

    // Consume the stream, logging each individual chunk
    while let Some(Ok(chunk)) = stream.next().await {
        console::log_1(&chunk);
    }

    Ok(())
}