Playing audio from url in Rust

Question

I have used rodio crate for playing audio from local file, by going through docs, but not able to figure out how to play audio using url.

Answer 1

Here is a simple example using blocking reqwest. This downloads the entire audio file into memory before it starts playing.

use std::io::{Write, Read, Cursor};
use rodio::Source;

fn main() {
    // Remember to add the "blocking" feature in the Cargo.toml for reqwest
    let resp = reqwest::blocking::get("http://websrvr90va.audiovideoweb.com/va90web25003/companions/Foundations%20of%20Rock/13.01.mp3")
        .unwrap();
    let mut cursor = Cursor::new(resp.bytes().unwrap()); // Adds Read and Seek to the bytes via Cursor
    let source = rodio::Decoder::new(cursor).unwrap(); // Decoder requires it's source to impl both Read and Seek
    let device = rodio::default_output_device().unwrap();
    rodio::play_raw(&device, source.convert_samples()); // Plays on a different thread
    loop {} // Don't exit immediately, so we can hear the audio
}

If you want to implement actual streaming, where parts of the audio file is downloaded then played, and more gets fetched later as it is needed, it gets quite a bit more complicated. See this entry about partial downloads in the Rust Cookbook: https://rust-lang-nursery.github.io/rust-cookbook/web/clients/download.html#make-a-partial-download-with-http-range-headers

I believe it can also be done easier with async reqwest, but I am still experimenting with that myself.