futures_unordered.rs

extern crate futures;
extern crate hyper;
extern crate tokio_core;
#[macro_use]
extern crate serde_derive;
extern crate serde;
extern crate serde_json;
extern crate hyper_tls;
extern crate time;
use time::PreciseTime;
use futures::{Future, Stream};
use hyper::Client;
use tokio_core::reactor::Core;
use hyper_tls::HttpsConnector;
use std::io::{self, Write};

#[derive(Serialize, Deserialize, Debug)]
struct Story {
    by: String,
    id: i32,
    score: i32,
    time: i32,
    title: String,
}


fn main() {
    let  start  = PreciseTime::now();

    let mut core = Core::new().unwrap();
    let client = ::hyper::Client::configure()
        .connector(::hyper_tls::HttpsConnector::new(4, &core.handle()).unwrap())
        .build(&core.handle());

    let uri = "https://hacker-news.firebaseio.com/v0/topstories.json".parse().unwrap();
    let work = client.get(uri).and_then(|res| {
        res.body().concat2().and_then(move |body| {
            let v: Vec<i32> = serde_json::from_slice(&body).unwrap();
            let mut vs = Vec::new();
            for i in 0..32 {
                let url = format!(
                    "https://hacker-news.firebaseio.com/v0/item/{}.json",
                    v[i],
                ).parse().unwrap();

                vs.push(client.get(url));
            }

            ::futures::stream::futures_unordered(vs).map(|res|{
                res.body().concat2().and_then(move |body|{
                    let value:Story = serde_json::from_slice(&body).unwrap();
                    println!("{:?}", value.title);
                    Ok(())
                })
            }).collect()

        })
    });
    let err= core.run(work).unwrap();
    //println!("{:?}", err);

    let end = PreciseTime::now();
    println!("{} seconds for whatever you did.", start.to(end));
}