Hyper client after v0.3.15 can't connect to some nginx servers with ConnectionOption::Close

[amoskvin]

Starting with commit 1e72a8a, Hyper errors out when trying to connect to some servers with ConnectionOption::Close header set. A common pattern seems to be that they're running nginx.

Here's a modified version of the example client:

extern crate hyper;

use std::io::Read;

use hyper::Client;
use hyper::header::Connection;
use hyper::header::ConnectionOption;

fn main() {
    for url in vec![
            "http://doc.rust-lang.org",
            "http://www.linode.com",
            "http://digitalocean.com",
            "http://www.reddit.com",
            "http://www.kernel.org",
            "http://www.gooogle.com",
        ]
    {
        run(url);
    }
}

fn run(url: &str) {
    println!("Retrieve {}:", url);
    let mut client = Client::new();
    let result = client.get(url)
        .header(Connection(vec![ConnectionOption::Close]))
        .send();

    match result {
        Ok(mut res) => {
                let mut body = String::new();
                res.read_to_string(&mut body).unwrap();
                println!("Success: {} bytes", body.len());
            },
        Err(_) => {
                println!("Failed: {:?}", result);
            },
    }
    println!("");
}

$ cargo update; cargo run
    Updating registry `https://github.com/rust-lang/crates.io-index`
   Compiling hyper v0.4.0 (file:///home/alec/test1)
   Compiling test1 v0.1.0 (file:///home/alec/test1)
     Running `target/debug/test1`
Retrieve http://doc.rust-lang.org:
Failed: Err(Io(Error { repr: Custom(Custom { kind: ConnectionAborted, error: StringError("Connection closed") }) }))

Retrieve http://www.linode.com:
Failed: Err(Io(Error { repr: Custom(Custom { kind: ConnectionAborted, error: StringError("Connection closed") }) }))

Retrieve http://digitalocean.com:
Failed: Err(Io(Error { repr: Custom(Custom { kind: ConnectionAborted, error: StringError("Connection closed") }) }))

Retrieve http://www.reddit.com:
Failed: Err(Io(Error { repr: Custom(Custom { kind: ConnectionAborted, error: StringError("Connection closed") }) }))

Retrieve http://www.kernel.org:
Failed: Err(Io(Error { repr: Custom(Custom { kind: ConnectionAborted, error: StringError("Connection closed") }) }))

Retrieve http://www.gooogle.com:
Success: 52184 bytes

$ cargo update; cargo run
    Updating registry `https://github.com/rust-lang/crates.io-index`
   Compiling hyper v0.3.15 (file:///home/alec/test1)
   Compiling test1 v0.1.0 (file:///home/alec/test1)
     Running `target/debug/test1`
Retrieve http://doc.rust-lang.org:
Success: 6414 bytes

Retrieve http://www.linode.com:
Success: 19898 bytes

Retrieve http://digitalocean.com:
Success: 19559 bytes

Retrieve http://www.reddit.com:
Success: 114095 bytes

Retrieve http://www.kernel.org:
Success: 19090 bytes

Retrieve http://www.gooogle.com:
Success: 52216 bytes

$ rustc --version
rustc 1.0.0-beta.4 (built 2015-05-09)