download.rs

use super::downloader::HttpClient;
use hyper;
use hyper::rt::{Future, Stream};
use std::error::Error;
use std::io::{Error as IOError, Read};
use std::sync::{atomic, mpsc, Arc};

pub struct Download {
    uri: String,
    body: mpsc::Receiver<hyper::Chunk>,
    downloaded_bytes: Arc<atomic::AtomicUsize>,
    buffer: Vec<u8>,
}

fn log_error(err: impl Error) {
    println!("Error: {}", err.to_string());
}

impl Download {
    pub fn fetch(uri: &str, client: &HttpClient) -> (Download, impl Future<Item = (), Error = ()>) {
        let (sender, receiver) = mpsc::channel();
        let download = Download {
            uri: uri.to_owned(),
            body: receiver,
            downloaded_bytes: Arc::new(atomic::AtomicUsize::new(0)),
            buffer: Vec::new(),
        };

        let uri = download.uri.parse().unwrap();
        let future = client.get(uri).map_err(log_error).and_then(move |res| {
            res.into_body()
                .map_err(log_error)
                .for_each(move |chunk| sender.send(chunk).map_err(log_error))
        });

        (download, future)
    }
}