Rust Hyper server with shared immutable access to file

main.rs

extern crate hyper;

use std::fs::File;
use std::io::prelude::*;

use hyper::{Body, Response, Server};
use hyper::service::service_fn_ok;
use hyper::rt::{self, Future};


fn get_html() -> std::io::Result<(String)> {
    let mut file = File::open("web/index.html")?;
    let mut contents = String::new();
    file.read_to_string(&mut contents)?;
    return Ok(contents);
}

fn main() {
    let addr = ([127, 0, 0, 1], 3000).into();

    // How can I move the get_html call here?
    let new_service = move || {
        service_fn_ok(|_| {
            let content = get_html().unwrap();
            Response::new(Body::from(content))
        })
    };

    let server = Server::bind(&addr)
        .serve(new_service)
        .map_err(|e| eprintln!("server error: {}", e));

    println!("Listening on http://{}", addr);

    rt::run(server);
}