ImportResult becomes a result

src/blockchain.rs

@@ -200,11 +200,16 @@ impl BlockChain {
 	///   ```json
 	///   { blocks: [B4, B3, A3, A4], ancestor: A2, index: 2 }
 	///   ```
-	pub fn tree_route(&self, from: H256, to: H256) -> TreeRoute {
+	pub fn tree_route(&self, from: H256, to: H256) -> Option<TreeRoute> {
-		let from_details = self.block_details(&from).expect("from hash is invalid!");
+		let from_details = match self.block_details(&from) {
-		let to_details = self.block_details(&to).expect("to hash is invalid!");
+			Some(h) => h,
-
+			None => return None,
-		self._tree_route((from_details, from), (to_details, to))
+		};
+		let to_details = match self.block_details(&to) {
+			Some(h) => h,
+			None => return None,
+		};
+		Some(self._tree_route((from_details, from), (to_details, to)))
 	}
 
 	/// Similar to `tree_route` function, but can be used to return a route
@@ -597,52 +602,52 @@ mod tests {
 		assert_eq!(bc.block_hash(&U256::from(3)).unwrap(), b3a_hash);
 
 		// test trie route
-		let r0_1 = bc.tree_route(genesis_hash.clone(), b1_hash.clone());
+		let r0_1 = bc.tree_route(genesis_hash.clone(), b1_hash.clone()).unwrap();
 		assert_eq!(r0_1.ancestor, genesis_hash);
 		assert_eq!(r0_1.blocks, [b1_hash.clone()]);
 		assert_eq!(r0_1.index, 0);
 
-		let r0_2 = bc.tree_route(genesis_hash.clone(), b2_hash.clone());
+		let r0_2 = bc.tree_route(genesis_hash.clone(), b2_hash.clone()).unwrap();
 		assert_eq!(r0_2.ancestor, genesis_hash);
 		assert_eq!(r0_2.blocks, [b1_hash.clone(), b2_hash.clone()]);
 		assert_eq!(r0_2.index, 0);
 
-		let r1_3a = bc.tree_route(b1_hash.clone(), b3a_hash.clone());
+		let r1_3a = bc.tree_route(b1_hash.clone(), b3a_hash.clone()).unwrap();
 		assert_eq!(r1_3a.ancestor, b1_hash);
 		assert_eq!(r1_3a.blocks, [b2_hash.clone(), b3a_hash.clone()]);
 		assert_eq!(r1_3a.index, 0);
 
-		let r1_3b = bc.tree_route(b1_hash.clone(), b3b_hash.clone());
+		let r1_3b = bc.tree_route(b1_hash.clone(), b3b_hash.clone()).unwrap();
 		assert_eq!(r1_3b.ancestor, b1_hash);
 		assert_eq!(r1_3b.blocks, [b2_hash.clone(), b3b_hash.clone()]);
 		assert_eq!(r1_3b.index, 0);
 
-		let r3a_3b = bc.tree_route(b3a_hash.clone(), b3b_hash.clone());
+		let r3a_3b = bc.tree_route(b3a_hash.clone(), b3b_hash.clone()).unwrap();
 		assert_eq!(r3a_3b.ancestor, b2_hash);
 		assert_eq!(r3a_3b.blocks, [b3a_hash.clone(), b3b_hash.clone()]);
 		assert_eq!(r3a_3b.index, 1);
 
-		let r1_0 = bc.tree_route(b1_hash.clone(), genesis_hash.clone());
+		let r1_0 = bc.tree_route(b1_hash.clone(), genesis_hash.clone()).unwrap();
 		assert_eq!(r1_0.ancestor, genesis_hash);
 		assert_eq!(r1_0.blocks, [b1_hash.clone()]);
 		assert_eq!(r1_0.index, 1);
 
-		let r2_0 = bc.tree_route(b2_hash.clone(), genesis_hash.clone());
+		let r2_0 = bc.tree_route(b2_hash.clone(), genesis_hash.clone()).unwrap();
 		assert_eq!(r2_0.ancestor, genesis_hash);
 		assert_eq!(r2_0.blocks, [b2_hash.clone(), b1_hash.clone()]);
 		assert_eq!(r2_0.index, 2);
 
-		let r3a_1 = bc.tree_route(b3a_hash.clone(), b1_hash.clone());
+		let r3a_1 = bc.tree_route(b3a_hash.clone(), b1_hash.clone()).unwrap();
 		assert_eq!(r3a_1.ancestor, b1_hash);
 		assert_eq!(r3a_1.blocks, [b3a_hash.clone(), b2_hash.clone()]);
 		assert_eq!(r3a_1.index, 2);
 
-		let r3b_1 = bc.tree_route(b3b_hash.clone(), b1_hash.clone());
+		let r3b_1 = bc.tree_route(b3b_hash.clone(), b1_hash.clone()).unwrap();
 		assert_eq!(r3b_1.ancestor, b1_hash);
 		assert_eq!(r3b_1.blocks, [b3b_hash.clone(), b2_hash.clone()]);
 		assert_eq!(r3b_1.index, 2);
 
-		let r3b_3a = bc.tree_route(b3b_hash.clone(), b3a_hash.clone());
+		let r3b_3a = bc.tree_route(b3b_hash.clone(), b3a_hash.clone()).unwrap();
 		assert_eq!(r3b_3a.ancestor, b2_hash);
 		assert_eq!(r3b_3a.blocks, [b3b_hash.clone(), b3a_hash.clone()]);
 		assert_eq!(r3b_3a.index, 1);

src/client.rs

@@ -2,21 +2,14 @@ use std::sync::Arc;
 use util::*;
 use blockchain::BlockChain;
 use views::BlockView;
-
+use error::ImportError;
-/// Status for a block in a queue.
-pub enum QueueStatus {
-	/// Part of the known chain.
-	Known,
-	/// Part of the unknown chain.
-	Unknown,
-}
 
 /// General block status
 pub enum BlockStatus {
 	/// Part of the blockchain.
 	InChain,
 	/// Queued for import.
-	Queued(QueueStatus),
+	Queued,
 	/// Known as bad.
 	Bad,
 	/// Unknown.
@@ -24,16 +17,7 @@ pub enum BlockStatus {
 }
 
 /// Result of import block operation.
-pub enum ImportResult {
+pub type ImportResult = Result<(), ImportError>;
-	/// Added to import queue.
-	Queued(QueueStatus),
-	/// Already in the chain.
-	AlreadyInChain,
-	/// Already queued for import.
-	AlreadyQueued(QueueStatus),
-	/// Bad or already known as bad.
-	Bad,
-}
 
 /// Information about the blockchain gthered together.
 pub struct BlockChainInfo {
@@ -88,7 +72,7 @@ pub trait BlockChainClient : Sync {
 
 	/// Get a tree route between `from` and `to`.
 	/// See `BlockChain::tree_route`.
-	fn tree_route(&self, from: &H256, to: &H256) -> TreeRoute;
+	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute>;
 
 	/// Get latest state node
 	fn state_data(&self, hash: &H256) -> Option<Bytes>;
@@ -165,7 +149,7 @@ impl BlockChainClient for Client {
 		}
 	}
 
-	fn tree_route(&self, from: &H256, to: &H256) -> TreeRoute {
+	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute> {
 		self.chain.tree_route(from.clone(), to.clone())
 	}
 
@@ -184,11 +168,11 @@ impl BlockChainClient for Client {
 			let header = block.header_view();
 			let hash = header.sha3();
 			if self.chain.is_known(&hash) {
-				return ImportResult::Bad;
+				return Err(ImportError::AlreadyInChain);
 			}
 		}
 		self.chain.insert_block(bytes);
-		ImportResult::Queued(QueueStatus::Known)
+		Ok(())
 	}
 
 	fn queue_status(&self) -> BlockQueueStatus {

src/error.rs

@@ -23,6 +23,13 @@ pub enum BlockError {
 	InvalidSealArity(Mismatch<usize>),
 }
 
+#[derive(Debug)]
+pub enum ImportError {
+	Bad(BlockError),
+	AlreadyInChain,
+	AlreadyQueued,
+}
+
 #[derive(Debug)]
 /// General error type which should be capable of representing all errors in ethcore.
 pub enum Error {

src/queue.rs

@@ -1,26 +1,24 @@
 use std::sync::Arc;
-//use util::bytes::*;
+use util::*;
-use util::sha3::*;
 use blockchain::BlockChain;
 use client::{QueueStatus, ImportResult};
 use views::{BlockView};
 
-
+/// A queue of blocks. Sits between network or other I/O and the BlockChain.
-pub struct BlockQueue {
+/// Sorts them ready for blockchain insertion.
-	chain: Arc<BlockChain>
+pub struct BlockQueue;
-}
 
 impl BlockQueue {
-	pub fn new(chain: Arc<BlockChain>) -> BlockQueue {
+	/// Creates a new queue instance.
-		BlockQueue {
+	pub fn new() -> BlockQueue {
-			chain: chain
-		}
 	}
 
+	/// Clear the queue and stop verification activity.
 	pub fn clear(&mut self) {
 	}
 
-	pub fn import_block(&mut self, bytes: &[u8]) -> ImportResult {
+	/// Add a block to the queue.
+	pub fn import_block(&mut self, bytes: &[u8], bc: &mut BlockChain) -> ImportResult {
 		//TODO: verify block
 		{
 			let block = BlockView::new(bytes);
@@ -30,7 +28,7 @@ impl BlockQueue {
 				return ImportResult::Bad;
 			}
 		}
-		self.chain.insert_block(bytes);
+		bc.insert_block(bytes);
 		ImportResult::Queued(QueueStatus::Known)
 	}
 }

src/sync/chain.rs

@@ -17,8 +17,9 @@ use util::*;
 use std::mem::{replace};
 use views::{HeaderView};
 use header::{Header as BlockHeader};
-use client::{BlockNumber, BlockChainClient, BlockStatus, QueueStatus, ImportResult};
+use client::{BlockNumber, BlockChainClient, BlockStatus};
 use sync::range_collection::{RangeCollection, ToUsize, FromUsize};
+use error::*;
 use sync::io::SyncIo;
 
 impl ToUsize for BlockNumber {
@@ -76,12 +77,13 @@ struct HeaderId {
 }
 
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
+/// Sync state 
 pub enum SyncState {
 	/// Initial chain sync has not started yet
 	NotSynced,
 	/// Initial chain sync complete. Waiting for new packets
 	Idle,
-	/// Block downloading paused. Waiting for block queue to process blocks and free space
+	/// Block downloading paused. Waiting for block queue to process blocks and free some space
 	Waiting,
 	/// Downloading blocks
 	Blocks,
@@ -108,24 +110,33 @@ pub struct SyncStatus {
 }
 
 #[derive(PartialEq, Eq, Debug)]
+/// Peer data type requested
 enum PeerAsking {
 	Nothing,
 	BlockHeaders,
 	BlockBodies,
 }
 
+/// Syncing peer information
 struct PeerInfo {
+	/// eth protocol version
 	protocol_version: u32,
+	/// Peer chain genesis hash
 	genesis: H256,
+	/// Peer network id 
 	network_id: U256,
+	/// Peer best block hash
 	latest: H256,
+	/// Peer total difficulty
 	difficulty: U256,
+	/// Type of data currenty being requested from peer.
 	asking: PeerAsking,
+	/// A set of block numbers being requested
 	asking_blocks: Vec<BlockNumber>,
 }
 
-type Body = Bytes;
+/// Blockchain sync handler.
-
+/// See module documentation for more details.
 pub struct ChainSync {
 	/// Sync state
 	state: SyncState,
@@ -140,7 +151,7 @@ pub struct ChainSync {
 	/// Downloaded headers.
 	headers: Vec<(BlockNumber, Vec<Header>)>, //TODO: use BTreeMap once range API is sable. For now it is a vector sorted in descending order
 	/// Downloaded bodies
-	bodies: Vec<(BlockNumber, Vec<Body>)>, //TODO: use BTreeMap once range API is sable. For now it is a vector sorted in descending order
+	bodies: Vec<(BlockNumber, Vec<Bytes>)>, //TODO: use BTreeMap once range API is sable. For now it is a vector sorted in descending order
 	/// Peer info
 	peers: HashMap<PeerId, PeerInfo>,
 	/// Used to map body to header
@@ -390,31 +401,31 @@ impl ChainSync {
 		// TODO: Decompose block and add to self.headers and self.bodies instead
 		if header_view.number() == From::from(self.last_imported_block + 1) {
 			match io.chain().import_block(block_rlp.as_raw()) {
-				ImportResult::AlreadyInChain => {
+				Err(ImportError::AlreadyInChain) => {
 					trace!(target: "sync", "New block already in chain {:?}", h);
 				},
-				ImportResult::AlreadyQueued(_) => {
+				Err(ImportError::AlreadyQueued) => {
 					trace!(target: "sync", "New block already queued {:?}", h);
 				},
-				ImportResult::Queued(QueueStatus::Known) => {
+				Ok(()) => {
 					trace!(target: "sync", "New block queued {:?}", h);
 				},
-				ImportResult::Queued(QueueStatus::Unknown) => {
+				Err(e) => {
-					trace!(target: "sync", "New block unknown {:?}", h);
+					debug!(target: "sync", "Bad new block {:?} : {:?}", h, e);
-					//TODO: handle too many unknown blocks
-					let difficulty: U256 = try!(r.val_at(1));
-					let peer_difficulty = self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer").difficulty;
-					if difficulty > peer_difficulty {
-						trace!(target: "sync", "Received block {:?}  with no known parent. Peer needs syncing...", h);
-						self.sync_peer(io, peer_id, true);
-					}
-				},
-				ImportResult::Bad =>{
-					debug!(target: "sync", "Bad new block {:?}", h);
 					io.disable_peer(peer_id);
 				}
 			};
 		} 
+		else {
+			trace!(target: "sync", "New block unknown {:?}", h);
+			//TODO: handle too many unknown blocks
+			let difficulty: U256 = try!(r.val_at(1));
+			let peer_difficulty = self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer").difficulty;
+			if difficulty > peer_difficulty {
+				trace!(target: "sync", "Received block {:?}  with no known parent. Peer needs syncing...", h);
+				self.sync_peer(io, peer_id, true);
+			}
+		}
 		Ok(())
 	}
 
@@ -434,7 +445,7 @@ impl ChainSync {
 				BlockStatus::InChain  => {
 					trace!(target: "sync", "New block hash already in chain {:?}", h);
 				},
-				BlockStatus::Queued(_) => {
+				BlockStatus::Queued => {
 					trace!(target: "sync", "New hash block already queued {:?}", h);
 				},
 				BlockStatus::Unknown => {
@@ -642,27 +653,24 @@ impl ChainSync {
 				block_rlp.append_raw(body.at(1).as_raw(), 1);
 				let h = &headers.1[i].hash;
 				match io.chain().import_block(&block_rlp.out()) {
-					ImportResult::AlreadyInChain  => {
+					Err(ImportError::AlreadyInChain) => {
 						trace!(target: "sync", "Block already in chain {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 					},
-					ImportResult::AlreadyQueued(_)  => {
+					Err(ImportError::AlreadyQueued) => {
 						trace!(target: "sync", "Block already queued {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 					},
-					ImportResult::Queued(QueueStatus::Known) => {
+					Ok(()) => {
 						trace!(target: "sync", "Block queued {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 						imported += 1;
 					},
-					ImportResult::Queued(QueueStatus::Unknown) => {
+					Err(e) => {
-						panic!("Queued out of order block");
+						debug!(target: "sync", "Bad block {:?} : {:?}", h, e);
-					},
-					ImportResult::Bad =>{
-						debug!(target: "sync", "Bad block {:?}", h);
 						restart = true;
 					}
 				}

src/sync/io.rs

@@ -2,19 +2,28 @@ use client::BlockChainClient;
 use util::network::{HandlerIo, PeerId, PacketId,};
 use util::error::UtilError;
 
+/// IO interface for the syning handler.
+/// Provides peer connection management and an interface to the blockchain client.
+// TODO: ratings
 pub trait SyncIo {
+	/// Disable a peer
 	fn disable_peer(&mut self, peer_id: &PeerId);
+	/// Respond to current request with a packet. Can be called from an IO handler for incoming packet.
 	fn respond(&mut self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError>;
+	/// Send a packet to a peer.
 	fn send(&mut self, peer_id: PeerId, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError>;
+	/// Get the blockchain
 	fn chain<'s>(&'s mut self) -> &'s mut BlockChainClient;
 }
 
+/// Wraps `HandlerIo` and the blockchain client
 pub struct NetSyncIo<'s, 'h> where 'h:'s {
 	network: &'s mut HandlerIo<'h>,
 	chain: &'s mut BlockChainClient
 }
 
 impl<'s, 'h> NetSyncIo<'s, 'h> {
+	/// Creates a new instance from the `HandlerIo` and the blockchain client reference.
 	pub fn new(network: &'s mut HandlerIo<'h>, chain: &'s mut BlockChainClient) -> NetSyncIo<'s,'h> {
 		NetSyncIo {
 			network: network,

src/sync/tests.rs

@@ -6,7 +6,7 @@ use util::sha3::Hashable;
 use util::rlp::{self, Rlp, RlpStream, View, Stream};
 use util::network::{PeerId, PacketId};
 use util::error::UtilError;
-use client::{BlockChainClient, BlockStatus, BlockNumber, TreeRoute, BlockQueueStatus, BlockChainInfo, ImportResult, QueueStatus};
+use client::{BlockChainClient, BlockStatus, BlockNumber, TreeRoute, BlockQueueStatus, BlockChainInfo, ImportResult};
 use header::Header as BlockHeader;
 use sync::io::SyncIo;
 use sync::chain::ChainSync;
@@ -49,7 +49,7 @@ impl TestBlockChainClient {
 			rlp.append(&header);
 			rlp.append_raw(&rlp::NULL_RLP, 1);
 			rlp.append_raw(uncles.as_raw(), 1);
-			self.import_block(rlp.as_raw());
+			self.import_block(rlp.as_raw()).unwrap();
 		}
 	}
 }
@@ -100,12 +100,12 @@ impl BlockChainClient for TestBlockChainClient {
 		}
 	}
 
-	fn tree_route(&self, _from: &H256, _to: &H256) -> TreeRoute {
+	fn tree_route(&self, _from: &H256, _to: &H256) -> Option<TreeRoute> {
-		TreeRoute {
+		Some(TreeRoute {
 			blocks: Vec::new(),
 			ancestor: H256::new(),
 			index: 0
-		}
+		})
 	}
 
 	fn state_data(&self, _h: &H256) -> Option<Bytes> {
@@ -153,7 +153,7 @@ impl BlockChainClient for TestBlockChainClient {
 		else {
 			self.blocks.insert(header.hash(), b.to_vec());
 		}
-		ImportResult::Queued(QueueStatus::Known)
+		Ok(())
 	}
 
 	fn queue_status(&self) -> BlockQueueStatus {