openethereum/ethcore/src/miner/price_info.rs

102 lines
3.3 KiB
Rust

// Copyright 2015, 2016 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
use rustc_serialize::json::Json;
use std::thread;
use std::io::Read;
use std::time::Duration;
use std::str::FromStr;
use std::sync::mpsc;
use hyper::client::{Handler, Request, Response, Client};
use hyper::{Next, Encoder, Decoder};
use hyper::net::HttpStream;
#[derive(Debug)]
pub struct PriceInfo {
pub ethusd: f32,
}
pub struct SetPriceHandler<F: Fn(PriceInfo) + Sync + Send + 'static> {
set_price: F,
channel: mpsc::Sender<()>,
}
impl<F: Fn(PriceInfo) + Sync + Send + 'static> Drop for SetPriceHandler<F> {
fn drop(&mut self) {
let _ = self.channel.send(());
}
}
impl<F: Fn(PriceInfo) + Sync + Send + 'static> Handler<HttpStream> for SetPriceHandler<F> {
fn on_request(&mut self, _: &mut Request) -> Next { Next::read().timeout(Duration::from_secs(3)) }
fn on_request_writable(&mut self, _: &mut Encoder<HttpStream>) -> Next { Next::read().timeout(Duration::from_secs(3)) }
fn on_response(&mut self, _: Response) -> Next { Next::read().timeout(Duration::from_secs(3)) }
fn on_response_readable(&mut self, r: &mut Decoder<HttpStream>) -> Next {
let mut body = String::new();
let _ = r.read_to_string(&mut body).ok()
.and_then(|_| Json::from_str(&body).ok())
.and_then(|json| json.find_path(&["result", "ethusd"])
.and_then(|obj| match *obj {
Json::String(ref s) => Some((self.set_price)(PriceInfo {
ethusd: FromStr::from_str(s)
.expect("Etherscan API will always return properly formatted price; qed")
})),
_ => None,
}));
Next::end()
}
}
impl PriceInfo {
pub fn get<F: Fn(PriceInfo) + Sync + Send + 'static>(set_price: F) -> Result<(), ()> {
// TODO: Handle each error type properly
let client = Client::new().map_err(|_| ())?;
thread::spawn(move || {
let (tx, rx) = mpsc::channel();
let url = FromStr::from_str("http://api.etherscan.io/api?module=stats&action=ethprice")
.expect("string known to be a valid URL; qed");
let _ = client.request(
url,
SetPriceHandler {
set_price: set_price,
channel: tx,
}).ok().and_then(|_| rx.recv().ok());
client.close();
});
Ok(())
}
}
#[test] #[ignore]
fn should_get_price_info() {
use std::sync::Arc;
use std::time::Duration;
use util::log::init_log;
use util::{Condvar, Mutex};
init_log();
let done = Arc::new((Mutex::new(PriceInfo { ethusd: 0f32 }), Condvar::new()));
let rdone = done.clone();
PriceInfo::get(move |price| { let mut p = rdone.0.lock(); *p = price; rdone.1.notify_one(); }).unwrap();
let mut p = done.0.lock();
let t = done.1.wait_for(&mut p, Duration::from_millis(10000));
assert!(!t.timed_out());
assert!(p.ethusd != 0f32);
}