How to get the Authorization Bearer header?

Question

I would like to get the Authorization Bearer header for OAuth purposes, but it looks a bit confusing reading the docs

use nickel::{Nickel, JsonBody, HttpRouter, Request, Response, MiddlewareResult, MediaType};

    // Get the full Authorization header from the incoming request headers
    let auth_header = match request.origin.headers.get::<Authorization<Bearer>>() {
        Some(header) => header,
        None => panic!("No authorization header found")
    };

This generates the error:

src/main.rs:84:56: 84:86 error: the trait hyper::header::HeaderFormat is not implemented for the type hyper::header::common::authorization::Authorization<hyper::header::common::authorization::Bearer> [E0277]

Looking at implementation it appears for me to be correct:

https://github.com/hyperium/hyper/blob/master/src/header/common/authorization.rs

impl<S: Scheme + Any> HeaderFormat for Authorization<S> where <S as FromStr>::Err: 'static {
    fn fmt_header(&self, f: &mut fmt::Formatter) -> fmt::Result {
        if let Some(scheme) = <S as Scheme>::scheme() {
            try!(write!(f, "{} ", scheme))
        };
        self.0.fmt_scheme(f)
    }
}

https://github.com/auth0/rust-api-example/issues/1

Answer 1

Looking at the documentation for Authorization, we can see that it does indeed implement Header:

impl<S: Scheme + Any> Header for Authorization<S>
    where S::Err: 'static

So you were on the right track. My guess is that you are running into something more insidious: multiple versions of the same crate.

Specifically, the version of nickel that I compiled today (0.7.3), depends on hyper 0.6.16. However, if I add hyper = "*" to my Cargo.toml, then I also get the newest version of hyper - 0.7.0.

As unintuitive as it may seem, items from hyper 0.7 are not compatible with items from hyper 0.6. This is nothing specific about hyper either; it's true for all crates.

If you update your dependency to lock to the same version of hyper that nickel wants, then you should be good to go.

---

Cargo.toml

# ...

[dependencies]
hyper = "0.6.16"
nickel = "*"

src/main.rs

extern crate nickel;
extern crate hyper;

use hyper::header::{Authorization, Bearer};
use nickel::{HttpRouter, Request};

fn foo(request: Request) {
    // Get the full Authorization header from the incoming request headers
    let auth_header = match request.origin.headers.get::<Authorization<Bearer>>() {
        Some(header) => header,
        None => panic!("No authorization header found")
    };
}

fn main() {}