bobbobbio/http_io

HTTP client / server with limited dependencies

http_io

Crate containing HTTP client and server.

• Designed to have limited dependencies, supports #![no_std].
• Focus on streaming IO.
• Support for providing your own transport.
• Supports HTTPS

The no_std build requires nightly since it relies on the alloc crate.

Example

use http_io::error::Result;
use std::fs::File;
use std::io;

fn main() -> Result<()> {
    // Stream contents of url to stdout
    let mut body = http_io::client::get("https://postman-echo.com/get")?;
    io::copy(&mut body, &mut std::io::stdout())?;

    // Stream contents of file to remote server
    let file = File::open("src/client.rs")?;
    http_io::client::put("https://postman-echo.com/put", file)?;
    Ok(())
}

Choosing a TLS backend

By default http_io uses native-tls as its library for TLS (HTTPS support). It supports two other TLS libraries, rustls and openssl. These other "back-ends" can be selected using feaures

$ # If you want to use `rustls`:
$ cargo build --no-default-features --features std,ssl-rustls
$ # If you want to use `openssl`:
$ cargo build --no-default-features --features std,ssl-openssl

http_io's Issues

response lifetime appears to require 'static, which makes it tricky to pass references.

I am experimenting with serving camera images from an ESP32 microcontroller. It has a std environment available. In order to fetch the image, I must repeatedly communicate with the camera via SPI.

I store a reference to the camera in MyHandler and pass it to the CameraBody (: impl Read) , but when I wrap that CameraBody in a Box and an HttpResponse, I get

error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
  --> src/httpd.rs:45:24
   |
45 |             let body = CameraBody::new(self.camera, self.spi).map_err(|e| {
   |                        ^^^^^^^^^^^^^^^
   |
note: first, the lifetime cannot outlive the lifetime `'a` as defined here...
  --> src/httpd.rs:21:6
   |
21 | impl<'a, SPI, CS, I2C, ES, EI, S> HttpRequestHandler<S> for MyHandler<'a, SPI, CS, I2C, ES, EI>
   |      ^^
note: ...so that reference does not outlive borrowed content
  --> src/httpd.rs:45:40
   |
45 |             let body = CameraBody::new(self.camera, self.spi).map_err(|e| {
   |                                        ^^^^^^^^^^^
   = note: but, the lifetime must be valid for the static lifetime...
note: ...so that the types are compatible
  --> src/httpd.rs:66:9
   |
66 |         Ok(resp)
   |         ^^^^^^^^
   = note: expected `Result<HttpResponse<Box<(dyn std::io::Read + 'static)>>, HttpResponse<Box<(dyn std::io::Read + 'static)>>>`
              found `Result<HttpResponse<Box<dyn std::io::Read>>, HttpResponse<Box<dyn std::io::Read>>>`

I get the feeling I'm going to have to wrap some things in an Arc<Mutex<_>> to help them live longer. This will get significantly harder if I target a no_std environment (which often lack Arc or Mutex).

I can't help but wonder if the API could be upgraded to have a lifetime on the result of the get() function to simplify things.

SSL Client is missing proper certificate validation

The SSL client should verify that the certificate matches the hostname.
https://www.rfc-editor.org/rfc/rfc2818#section-3.1

HttpHeaders::get is case-sensitive

HTTP header field names are case-insensitive, but HttpHeaders::get does a case-sensitive lookup. For example, req.headers.get("Content-Length") does not work when the client sent content-length: 123.

Handle redirects properly

Implement this part of the RFC properly https://www.rfc-editor.org/rfc/rfc7231#section-6.4