stub implementations of light client trait

ethcore/src/light/client.rs

@@ -0,0 +1,95 @@
+// Copyright 2015, 2016 Ethcore (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/>.
+
+//! Light client implementation. Used for raw data queries as well as the header
+//! sync.
+
+use std::sync::Arc;
+
+use engines::Engine;
+use ids::BlockID;
+use miner::TransactionQueue;
+use service::ClientIoMessage;
+use block_import_error::BlockImportError;
+use block_status::BlockStatus;
+use verification::queue::{Config as QueueConfig, HeaderQueue, QueueInfo, Status};
+use transaction::SignedTransaction;
+
+use super::provider::{CHTProofRequest, Provider, ProofRequest};
+
+use io::IoChannel;
+use util::hash::H256;
+use util::Bytes;
+
+/// A light client.
+pub struct Client {
+	engine: Arc<Engine>,
+	header_queue: HeaderQueue,
+	message_channel: IoChannel<ClientIoMessage>,
+	transaction_queue: TransactionQueue,
+}
+
+impl Client {
+	/// Import a header as rlp-encoded bytes.
+	fn import_header(&self, bytes: Bytes) -> Result<H256, BlockImportError> {
+		let header = ::rlp::decode(&bytes);
+
+		self.header_queue.import(header).map_err(Into::into)
+	}
+
+	/// Whether the block is already known (but not necessarily part of the canonical chain)
+	fn is_known(&self, id: BlockID) -> bool {
+		false
+	}
+
+	/// Fetch a vector of all pending transactions.
+	fn pending_transactions(&self) -> Vec<SignedTransaction> {
+		self.transaction_queue.top_transactions()
+	}
+
+	/// Inquire about the status of a given block.
+	fn status(&self, id: BlockID) -> BlockStatus {
+		BlockStatus::Unknown
+	}
+}
+
+// stub implementation, can be partially implemented using LRU-caches
+// but will almost definitely never be able to provide complete responses.
+impl Provider for Client {
+	fn block_headers(&self, _block: H256, _skip: usize, _max: usize, _reverse: bool) -> Vec<Bytes> {
+		vec![]
+	}
+
+	fn block_bodies(&self, _blocks: Vec<H256>) -> Vec<Bytes> {
+		vec![]
+	}
+
+	fn receipts(&self, _blocks: Vec<H256>) -> Vec<Bytes> {
+		vec![]
+	}
+
+	fn proofs(&self, _requests: Vec<(H256, ProofRequest)>) -> Vec<Bytes> {
+		vec![]
+	}
+
+	fn code(&self, _accounts: Vec<(H256, H256)>) -> Vec<Bytes> {
+		vec![]
+	}
+
+	fn header_proofs(&self, _requests: Vec<CHTProofRequest>) -> Vec<Bytes> {
+		vec![]
+	}
+}

ethcore/src/light/mod.rs

@@ -0,0 +1,18 @@
+//! Light client logic and implementation.
+//!
+//! A "light" client stores very little chain-related data locally
+//! unlike a full node, which stores all blocks, headers, receipts, and more.
+//!
+//! This enables the client to have a much lower resource footprint in
+//! exchange for the cost of having to ask the network for state data
+//! while responding to queries. This makes a light client unsuitable for
+//! low-latency applications, but perfectly suitable for simple everyday
+//! use-cases like sending transactions from a personal account.
+//!
+//! It starts by performing a header-only sync, verifying every header in
+//! the chain.
+
+mod provider;
+mod client;
+
+pub use self::provider::{CHTProofRequest, ProofRequest, Provider};