#rocket #range-request #partial-content #rocket-rs #206


Rocket-rs 0.5.0-rc.3 responder to range requests using types that implement AsyncRead + AsyncSeek

6 releases

0.2.6 May 4, 2023
0.2.5 Aug 26, 2022
0.2.4 Aug 3, 2021
0.2.3 Sep 7, 2019

#35 in #rocket

MIT license

379 lines



A Rocket responder for types implementing the AsyncRead + AsyncSeek traits, such as files and rocket::futures::io::Cursor, that will respond to range requests with a 206 Partial Content response. The Content-Type can optionally be inferred by taking a sample of bytes from the beginning of the stream, or given manually. An Accept-Ranges: bytes header will be sent in all responses to notify browsers that range requests are supported for the resource.

This supports both single and multipart/byterange requests. https://tools.ietf.org/html/rfc7233


Add this to your dependencies.

rocket_seek_stream = {git="https://github.com/rydz/rocket_seek_stream"}


Serving a file from the disk

#![feature(proc_macro_hygiene, decl_macro)]
extern crate rocket;
use rocket_seek_stream::SeekStream;

fn home<'a>() -> std::io::Result<SeekStream<'a>> {

async fn main() {
    match rocket::build().mount("/", routes![home]).launch().await {
        Ok(_) => (),
        Err(e) => {
            eprintln!("Rocket stopped unexpectedly. (Error {})", e);

Serving an in memory buffer

fn cursor<'a>() -> SeekStream<'a> {
    let bytes = &include_bytes!("./fly_me_to_the_moon.webm")[..];
    let len = bytes.len();
    let stream = std::io::Cursor::new(bytes);

    SeekStream::with_opts(stream, len as u64, "video/webm")

Use cargo run --example server to run the example. run examples/download.sh to download the media it depends on using yt-dlp.


  • Write some tests

I've compared the output of the Golang stdlib http router's multipart response to what I output here and it looks about the same except for a small difference in whitespace.


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