openethereum/ethcore/light/src/client/service.rs

143 lines
4.1 KiB
Rust

// Copyright 2015-2019 Parity Technologies (UK) Ltd.
// This file is part of Parity Ethereum.
// Parity Ethereum 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 Ethereum 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 Ethereum. If not, see <http://www.gnu.org/licenses/>.
//! Minimal IO service for light client.
//! Just handles block import messages and passes them to the client.
use std::{fmt, sync::Arc};
use ethcore::{client::ClientIoMessage, error::Error as CoreError, spec::Spec};
use ethcore_blockchain::BlockChainDB;
use ethcore_db as db;
use io::{IoContext, IoError, IoHandler, IoService};
use cache::Cache;
use parking_lot::Mutex;
use super::{ChainDataFetcher, Client, Config as ClientConfig, LightChainNotify};
/// Errors on service initialization.
#[derive(Debug)]
pub enum Error {
/// Core error.
Core(CoreError),
/// I/O service error.
Io(IoError),
}
impl From<CoreError> for Error {
#[inline]
fn from(err: CoreError) -> Error {
Error::Core(err)
}
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
Error::Core(ref msg) => write!(f, "Core error: {}", msg),
Error::Io(ref err) => write!(f, "I/O service error: {}", err),
}
}
}
/// Light client service.
pub struct Service<T> {
client: Arc<Client<T>>,
io_service: IoService<ClientIoMessage>,
}
impl<T: ChainDataFetcher> Service<T> {
/// Start the service: initialize I/O workers and client itself.
pub fn start(
config: ClientConfig,
spec: &Spec,
fetcher: T,
db: Arc<dyn BlockChainDB>,
cache: Arc<Mutex<Cache>>,
) -> Result<Self, Error> {
let io_service = IoService::<ClientIoMessage>::start().map_err(Error::Io)?;
let client = Arc::new(Client::new(
config,
db.key_value().clone(),
db::COL_LIGHT_CHAIN,
spec,
fetcher,
io_service.channel(),
cache,
)?);
io_service
.register_handler(Arc::new(ImportBlocks(client.clone())))
.map_err(Error::Io)?;
spec.engine.register_client(Arc::downgrade(&client) as _);
Ok(Service { client, io_service })
}
/// Set the actor to be notified on certain chain events
pub fn add_notify(&self, notify: Arc<dyn LightChainNotify>) {
self.client.add_listener(Arc::downgrade(&notify));
}
/// Register an I/O handler on the service.
pub fn register_handler(
&self,
handler: Arc<dyn IoHandler<ClientIoMessage> + Send>,
) -> Result<(), IoError> {
self.io_service.register_handler(handler)
}
/// Get a handle to the client.
pub fn client(&self) -> &Arc<Client<T>> {
&self.client
}
}
struct ImportBlocks<T>(Arc<Client<T>>);
impl<T: ChainDataFetcher> IoHandler<ClientIoMessage> for ImportBlocks<T> {
fn message(&self, _io: &IoContext<ClientIoMessage>, message: &ClientIoMessage) {
if let ClientIoMessage::BlockVerified = *message {
self.0.import_verified();
}
}
}
#[cfg(test)]
mod tests {
use super::Service;
use ethcore::spec::Spec;
use cache::Cache;
use client::fetch;
use ethcore::test_helpers;
use parking_lot::Mutex;
use std::{sync::Arc, time::Duration};
#[test]
fn it_works() {
let db = test_helpers::new_db();
let spec = Spec::new_test();
let cache = Arc::new(Mutex::new(Cache::new(
Default::default(),
Duration::from_secs(6 * 3600),
)));
Service::start(Default::default(), &spec, fetch::unavailable(), db, cache).unwrap();
}
}