queue culling and informant

Cargo.lock

@@ -27,6 +27,7 @@ dependencies = [
  "ethsync 1.7.0",
  "evmbin 0.1.0",
  "fdlimit 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "futures 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.10.0-a.0 (git+https://github.com/paritytech/hyper)",
  "isatty 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "jsonrpc-core 7.0.0 (git+https://github.com/paritytech/jsonrpc.git?branch=parity-1.7)",

Cargo.toml

@@ -23,6 +23,7 @@ toml = "0.2"
 serde = "0.9"
 serde_json = "0.9"
 app_dirs = "1.1.1"
+futures = "0.1"
 fdlimit = "0.1"
 ws2_32-sys = "0.2"
 hyper = { default-features = false, git = "https://github.com/paritytech/hyper" }

ethcore/light/src/client/service.rs

@@ -50,7 +50,7 @@ impl fmt::Display for Error {
 /// Light client service.
 pub struct Service {
 	client: Arc<Client>,
-	_io_service: IoService<ClientIoMessage>,
+	io_service: IoService<ClientIoMessage>,
 }
 
 impl Service {
@@ -82,10 +82,15 @@ impl Service {
 		io_service.register_handler(Arc::new(ImportBlocks(client.clone()))).map_err(Error::Io)?;
 		Ok(Service {
 			client: client,
-			_io_service: io_service,
+			io_service: io_service,
 		})
 	}
 
+	/// Register an I/O handler on the service.
+	pub fn register_handler(&self, handler: Arc<IoHandler<ClientIoMessage> + Send>) -> Result<(), IoError> {
+		self.io_service.register_handler(handler)
+	}
+
 	/// Get a handle to the client.
 	pub fn client(&self) -> &Arc<Client> {
 		&self.client

parity/light_helpers/mod.rs

@@ -0,0 +1,21 @@
+// Copyright 2015-2017 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/>.
+
+//! Utilities and helpers for the light client.
+
+mod queue_cull;
+
+pub use self::queue_cull::QueueCull;

parity/light_helpers/queue_cull.rs

@@ -0,0 +1,99 @@
+// Copyright 2015-2017 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/>.
+
+//! Service for culling the light client's transaction queue.
+
+use std::sync::Arc;
+use std::time::Duration;
+
+use ethcore::service::ClientIoMessage;
+use ethsync::LightSync;
+use io::{IoContext, IoHandler, TimerToken};
+
+use light::client::Client;
+use light::on_demand::{request, OnDemand};
+use light::TransactionQueue;
+
+use futures::{future, stream, Future, Stream};
+
+use parity_reactor::Remote;
+
+use util::RwLock;
+
+// Attepmt to cull once every 10 minutes.
+const TOKEN: TimerToken = 1;
+const TIMEOUT_MS: u64 = 1000 * 60 * 10;
+
+// But make each attempt last only 9 minutes
+const PURGE_TIMEOUT_MS: u64 = 1000 * 60 * 9;
+
+/// Periodically culls the transaction queue of mined transactions.
+pub struct QueueCull {
+	/// A handle to the client, for getting the latest block header.
+	pub client: Arc<Client>,
+	/// A handle to the sync service.
+	pub sync: Arc<LightSync>,
+	/// The on-demand request service.
+	pub on_demand: Arc<OnDemand>,
+	/// The transaction queue.
+	pub txq: Arc<RwLock<TransactionQueue>>,
+	/// Event loop remote.
+	pub remote: Remote,
+}
+
+impl IoHandler<ClientIoMessage> for QueueCull {
+	fn initialize(&self, io: &IoContext<ClientIoMessage>) {
+		io.register_timer(TOKEN, TIMEOUT_MS).expect("Error registering timer");
+	}
+
+	fn timeout(&self, _io: &IoContext<ClientIoMessage>, timer: TimerToken) {
+		if timer != TOKEN { return }
+
+		let senders = self.txq.read().queued_senders();
+		if senders.is_empty() { return }
+
+		let (sync, on_demand, txq) = (self.sync.clone(), self.on_demand.clone(), self.txq.clone());
+		let best_header = self.client.best_block_header();
+		let start_nonce = self.client.engine().account_start_nonce();
+
+		info!(target: "cull", "Attempting to cull queued transactions from {} senders.", senders.len());
+		self.remote.spawn_with_timeout(move || {
+			let maybe_fetching = sync.with_context(move |ctx| {
+				// fetch the nonce of each sender in the queue.
+				let nonce_futures = senders.iter()
+					.map(|&address| request::Account { header: best_header.clone(), address: address })
+					.map(|request| on_demand.account(ctx, request))
+					.map(move |fut| fut.map(move |x| x.map(|acc| acc.nonce).unwrap_or(start_nonce)))
+					.zip(senders.iter())
+					.map(|(fut, &addr)| fut.map(move |nonce| (addr, nonce)));
+
+				// as they come in, update each sender to the new nonce.
+				stream::futures_unordered(nonce_futures)
+					.fold(txq, |txq, (address, nonce)| {
+						txq.write().cull(address, nonce);
+						future::ok(txq)
+					})
+					.map(|_| ()) // finally, discard the txq handle and log errors.
+					.map_err(|_| debug!(target: "cull", "OnDemand prematurely closed channel."))
+			});
+
+			match maybe_fetching {
+				Some(fut) => fut.boxed(),
+				None => future::ok(()).boxed(),
+			}
+		}, Duration::from_millis(PURGE_TIMEOUT_MS), || {})
+	}
+}

parity/main.rs

@@ -28,6 +28,7 @@ extern crate ctrlc;
 extern crate docopt;
 extern crate env_logger;
 extern crate fdlimit;
+extern crate futures;
 extern crate hyper;
 extern crate isatty;
 extern crate jsonrpc_core;
@@ -101,6 +102,7 @@ mod deprecated;
 mod dir;
 mod helpers;
 mod informant;
+mod light_helpers;
 mod migration;
 mod modules;
 mod params;

parity/run.rs

@@ -238,12 +238,24 @@ fn execute_light(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) ->
 	};
 	let light_sync = LightSync::new(sync_params).map_err(|e| format!("Error starting network: {}", e))?;
 	let light_sync = Arc::new(light_sync);
-	light_sync.start_network();
 
-	// start RPCs.
 	// spin up event loop
 	let event_loop = EventLoop::spawn();
 
+	// queue cull service.
+	let queue_cull = Arc::new(::light_helpers::QueueCull {
+		client: service.client().clone(),
+		sync: light_sync.clone(),
+		on_demand: on_demand.clone(),
+		txq: txq.clone(),
+		remote: event_loop.remote(),
+	});
+
+	service.register_handler(queue_cull).map_err(|e| format!("Error attaching service: {:?}", e))?;
+
+	// start the network.
+	light_sync.start_network();
+
 	// fetch service
 	let fetch = FetchClient::new().map_err(|e| format!("Error starting fetch client: {:?}", e))?;
 	let passwords = passwords_from_files(&cmd.acc_conf.password_files)?;
@@ -253,6 +265,7 @@ fn execute_light(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) ->
 	let rpc_stats = Arc::new(informant::RpcStats::default());
 	let signer_path = cmd.signer_conf.signer_path.clone();
 
+	// start RPCs
 	let deps_for_rpc_apis = Arc::new(rpc_apis::LightDependencies {
 		signer_service: Arc::new(rpc_apis::SignerService::new(move || {
 			signer::generate_new_token(signer_path.clone()).map_err(|e| format!("{:?}", e))
@@ -299,6 +312,14 @@ fn execute_light(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) ->
 
 	// TODO: Dapps
 
+	// minimal informant thread. Just prints block number every 5 seconds.
+	// TODO: integrate with informant.rs
+	let informant_client = service.client().clone();
+	::std::thread::spawn(move || loop {
+		info!("#{}", informant_client.best_block_header().number());
+		::std::thread::sleep(::std::time::Duration::from_secs(5));
+	});
+
 	// wait for ctrl-c.
 	Ok(wait_for_exit(panic_handler, None, None, can_restart))
 }