Merge branch 'master' into client-ipc-refact

2016-06-30 20:32:13 +03:00 · 2016-06-30 20:32:13 +03:00 · 97eb311cb0
commit 97eb311cb0
parent 080b50809a 673c5afd4d
34 changed files with 463 additions and 91 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@ -261,6 +261,7 @@ dependencies = [
 "ethjson 0.1.0",
 "ethstore 0.1.0",
 "heapsize 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hyper 0.9.4 (git+https://github.com/ethcore/hyper)",
 "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "num_cpus 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
@ -285,7 +286,7 @@ dependencies = [
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "mime_guess 1.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "parity-dapps 0.3.0 (git+https://github.com/ethcore/parity-dapps-rs.git)",
- "parity-dapps-builtins 0.5.1 (git+https://github.com/ethcore/parity-dapps-builtins-rs.git)",
+ "parity-dapps-builtins 0.5.2 (git+https://github.com/ethcore/parity-dapps-builtins-rs.git)",
 "parity-dapps-status 0.5.0 (git+https://github.com/ethcore/parity-dapps-status-rs.git)",
 "parity-dapps-wallet 0.6.1 (git+https://github.com/ethcore/parity-dapps-wallet-rs.git)",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
@ -378,6 +379,7 @@ dependencies = [
 name = "ethcore-util"
 version = "1.3.0"
 dependencies = [
+ "ansi_term 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "arrayvec 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
 "bigint 0.1.0",
 "chrono 0.2.22 (registry+https://github.com/rust-lang/crates.io-index)",
@ -549,7 +551,7 @@ dependencies = [
 [[package]]
 name = "hyper"
 version = "0.9.4"
-source = "git+https://github.com/ethcore/hyper#7ccfcb2aa7e6aa6300efa8cebd6a0e6ce55582ea"
+source = "git+https://github.com/ethcore/hyper#9e346c1d4bc30cd4142dea9d8a0b117d30858ca4"
 dependencies = [
 "cookie 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "httparse 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@ -558,7 +560,7 @@ dependencies = [
 "mime 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "rotor 0.6.3 (git+https://github.com/ethcore/rotor)",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
- "spmc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "spmc 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)",
 "traitobject 0.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "typeable 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@ -911,8 +913,8 @@ dependencies = [

 [[package]]
 name = "parity-dapps-builtins"
-version = "0.5.1"
-source = "git+https://github.com/ethcore/parity-dapps-builtins-rs.git#7408838e8ca3b57c6b0cf5da2e31e0e275959955"
+version = "0.5.2"
+source = "git+https://github.com/ethcore/parity-dapps-builtins-rs.git#01af2091d5d70dfe0aecbfd96308f0ae79fc61e6"
 dependencies = [
 "parity-dapps 0.3.0 (git+https://github.com/ethcore/parity-dapps-rs.git)",
 ]
@ -1224,7 +1226,7 @@ dependencies = [

 [[package]]
 name = "spmc"
-version = "0.2.0"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"

 [[package]]
--- a/dapps/Cargo.toml
+++ b/dapps/Cargo.toml
@ -23,7 +23,7 @@ ethcore-util = { path = "../util" }
 parity-dapps = { git = "https://github.com/ethcore/parity-dapps-rs.git", version = "0.3" }
 # List of apps
 parity-dapps-status = { git = "https://github.com/ethcore/parity-dapps-status-rs.git", version = "0.5.0" }
-parity-dapps-builtins = { git = "https://github.com/ethcore/parity-dapps-builtins-rs.git", version = "0.5.0" }
+parity-dapps-builtins = { git = "https://github.com/ethcore/parity-dapps-builtins-rs.git", version = "0.5.2" }
 parity-dapps-wallet = { git = "https://github.com/ethcore/parity-dapps-wallet-rs.git", version = "0.6.0", optional = true }
 parity-dapps-dao = { git = "https://github.com/ethcore/parity-dapps-dao-rs.git", version = "0.4.0", optional = true }
 parity-dapps-makerotc = { git = "https://github.com/ethcore/parity-dapps-makerotc-rs.git", version = "0.3.0", optional = true }
--- a/ethcore/Cargo.toml
+++ b/ethcore/Cargo.toml
@ -33,6 +33,10 @@ rayon = "0.3.1"
 ethstore = { path = "../ethstore" }
 semver = "0.2"

+[dependencies.hyper]
+git = "https://github.com/ethcore/hyper"
+default-features = false
+
 [features]
 jit = ["evmjit"]
 evm-debug = []
--- a/ethcore/src/account.rs
+++ b/ethcore/src/account.rs
@ -108,6 +108,12 @@ impl Account {
 		self.code_cache = code;
 	}

+	/// Reset this account's code to the given code.
+	pub fn reset_code(&mut self, code: Bytes) {
+		self.code_hash = None;
+		self.init_code(code);
+	}
+
 	/// Set (and cache) the contents of the trie's storage at `key` to `value`.
 	pub fn set_storage(&mut self, key: H256, value: H256) {
 		self.storage_overlay.borrow_mut().insert(key, (Filth::Dirty, value));
@ -336,6 +342,21 @@ mod tests {
 		assert_eq!(a.code_hash().hex(), "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb");
 	}

+	#[test]
+	fn reset_code() {
+		let mut a = Account::new_contract(69.into(), 0.into());
+		let mut db = MemoryDB::new();
+		let mut db = AccountDBMut::new(&mut db, &Address::new());
+		a.init_code(vec![0x55, 0x44, 0xffu8]);
+		assert_eq!(a.code_hash(), SHA3_EMPTY);
+		a.commit_code(&mut db);
+		assert_eq!(a.code_hash().hex(), "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb");
+		a.reset_code(vec![0x55]);
+		assert_eq!(a.code_hash(), SHA3_EMPTY);
+		a.commit_code(&mut db);
+		assert_eq!(a.code_hash().hex(), "37bf2238b11b68cdc8382cece82651b59d3c3988873b6e0f33d79694aa45f1be");
+	}
+
 	#[test]
 	fn rlpio() {
 		let a = Account::new(U256::from(69u8), U256::from(0u8), HashMap::new(), Bytes::new());
@ -348,7 +369,6 @@ mod tests {

 	#[test]
 	fn new_account() {
-
 		let a = Account::new(U256::from(69u8), U256::from(0u8), HashMap::new(), Bytes::new());
 		assert_eq!(a.rlp().to_hex(), "f8448045a056e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421a0c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470");
 		assert_eq!(a.balance(), &U256::from(69u8));
@ -359,7 +379,6 @@ mod tests {

 	#[test]
 	fn create_account() {
-
 		let a = Account::new(U256::from(69u8), U256::from(0u8), HashMap::new(), Bytes::new());
 		assert_eq!(a.rlp().to_hex(), "f8448045a056e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421a0c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470");
 	}
--- a/ethcore/src/block.rs
+++ b/ethcore/src/block.rs
@ -164,6 +164,12 @@ pub trait IsBlock {
 	fn uncles(&self) -> &Vec<Header> { &self.block().base.uncles }
 }

+/// Trait for a object that has a state database.
+pub trait Drain {
+	/// Drop this object and return the underlieing database.
+	fn drain(self) -> Box<JournalDB>;
+}
+
 impl IsBlock for ExecutedBlock {
 	fn block(&self) -> &ExecutedBlock { self }
 }
@ -436,9 +442,11 @@ impl LockedBlock {
 			_ => Ok(SealedBlock { block: s.block, uncle_bytes: s.uncle_bytes }),
 		}
 	}
+}

+impl Drain for LockedBlock {
 	/// Drop this object and return the underlieing database.
-	pub fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
+	fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
 }

 impl SealedBlock {
@ -450,9 +458,11 @@ impl SealedBlock {
 		block_rlp.append_raw(&self.uncle_bytes, 1);
 		block_rlp.out()
 	}
+}

+impl Drain for SealedBlock {
 	/// Drop this object and return the underlieing database.
-	pub fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
+	fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
 }

 impl IsBlock for SealedBlock {
--- a/ethcore/src/client/mod.rs
+++ b/ethcore/src/client/mod.rs
@ -37,7 +37,7 @@ use util::numbers::U256;
 use util::Itertools;
 use blockchain::TreeRoute;
 use block_queue::BlockQueueInfo;
-use block::OpenBlock;
+use block::{OpenBlock, SealedBlock};
 use header::{BlockNumber, Header};
 use transaction::{LocalizedTransaction, SignedTransaction};
 use log_entry::LocalizedLogEntry;
@ -244,4 +244,7 @@ pub trait MiningBlockChainClient : BlockChainClient {

 	/// Returns EvmFactory.
 	fn vm_factory(&self) -> &EvmFactory;
+
+	/// Import sealed block. Skips all verifications.
+	fn import_sealed_block(&self, block: SealedBlock) -> ImportResult;
 }
--- a/ethcore/src/client/test_client.rs
+++ b/ethcore/src/client/test_client.rs
@ -33,7 +33,7 @@ use miner::{Miner, MinerService};
 use spec::Spec;

 use block_queue::BlockQueueInfo;
-use block::OpenBlock;
+use block::{OpenBlock, SealedBlock};
 use executive::Executed;
 use error::{ExecutionError};
 use trace::LocalizedTrace;
@ -249,6 +249,10 @@ impl MiningBlockChainClient for TestBlockChainClient {
 	fn vm_factory(&self) -> &EvmFactory {
 		unimplemented!();
 	}
+
+	fn import_sealed_block(&self, _block: SealedBlock) -> ImportResult {
+		unimplemented!();
+	}
 }

 impl BlockChainClient for TestBlockChainClient {
--- a/ethcore/src/ethereum/ethash.rs
+++ b/ethcore/src/ethereum/ethash.rs
@ -14,9 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

-extern crate ethash;
-
-use self::ethash::{quick_get_difficulty, EthashManager, H256 as EH256};
+use ethash::{quick_get_difficulty, EthashManager, H256 as EH256};
 use common::*;
 use block::*;
 use spec::CommonParams;
--- a/ethcore/src/lib.rs
+++ b/ethcore/src/lib.rs
@ -91,6 +91,8 @@ extern crate ethjson;
 extern crate bloomchain;
 #[macro_use] extern crate ethcore_ipc as ipc;
 extern crate rayon;
+extern crate hyper;
+extern crate ethash;
 pub extern crate ethstore;
 extern crate semver;

--- a/ethcore/src/miner/miner.rs
+++ b/ethcore/src/miner/miner.rs
@ -16,8 +16,10 @@

 use rayon::prelude::*;
 use std::sync::atomic::AtomicBool;
+use std::time::{Instant, Duration};

 use util::*;
+use util::Colour::White;
 use account_provider::AccountProvider;
 use views::{BlockView, HeaderView};
 use client::{MiningBlockChainClient, Executive, Executed, EnvInfo, TransactOptions, BlockID, CallAnalytics};
@ -28,6 +30,7 @@ use receipt::{Receipt};
 use spec::Spec;
 use engine::Engine;
 use miner::{MinerService, MinerStatus, TransactionQueue, AccountDetails, TransactionImportResult, TransactionOrigin};
+use miner::work_notify::WorkPoster;

 /// Different possible definitions for pending transaction set.
 #[derive(Debug)]
@ -44,29 +47,41 @@ pub enum PendingSet {
 /// Configures the behaviour of the miner.
 #[derive(Debug)]
 pub struct MinerOptions {
+	/// URLs to notify when there is new work.
+	pub new_work_notify: Vec<String>,
 	/// Force the miner to reseal, even when nobody has asked for work.
 	pub force_sealing: bool,
 	/// Reseal on receipt of new external transactions.
 	pub reseal_on_external_tx: bool,
 	/// Reseal on receipt of new local transactions.
 	pub reseal_on_own_tx: bool,
+	/// Minimum period between transaction-inspired reseals.
+	pub reseal_min_period: Duration,
 	/// Maximum amount of gas to bother considering for block insertion.
 	pub tx_gas_limit: U256,
 	/// Maximum size of the transaction queue.
 	pub tx_queue_size: usize,
 	/// Whether we should fallback to providing all the queue's transactions or just pending.
 	pub pending_set: PendingSet,
+	/// How many historical work packages can we store before running out?
+	pub work_queue_size: usize,
+	/// Can we submit two different solutions for the same block and expect both to result in an import?
+	pub enable_resubmission: bool,
 }

 impl Default for MinerOptions {
 	fn default() -> Self {
 		MinerOptions {
+			new_work_notify: vec![],
 			force_sealing: false,
 			reseal_on_external_tx: true,
 			reseal_on_own_tx: true,
 			tx_gas_limit: !U256::zero(),
 			tx_queue_size: 1024,
 			pending_set: PendingSet::AlwaysQueue,
+			reseal_min_period: Duration::from_secs(0),
+			work_queue_size: 20,
+			enable_resubmission: true,
 		}
 	}
 }
@ -80,6 +95,7 @@ pub struct Miner {
 	// for sealing...
 	options: MinerOptions,
 	sealing_enabled: AtomicBool,
+	next_allowed_reseal: Mutex<Instant>,
 	sealing_block_last_request: Mutex<u64>,
 	gas_range_target: RwLock<(U256, U256)>,
 	author: RwLock<Address>,
@ -87,6 +103,7 @@ pub struct Miner {
 	spec: Spec,

 	accounts: Option<Arc<AccountProvider>>,
+	work_poster: Option<WorkPoster>,
 }

 impl Miner {
@ -96,29 +113,34 @@ impl Miner {
 			transaction_queue: Mutex::new(TransactionQueue::new()),
 			options: Default::default(),
 			sealing_enabled: AtomicBool::new(false),
+			next_allowed_reseal: Mutex::new(Instant::now()),
 			sealing_block_last_request: Mutex::new(0),
-			sealing_work: Mutex::new(UsingQueue::new(5)),
+			sealing_work: Mutex::new(UsingQueue::new(20)),
 			gas_range_target: RwLock::new((U256::zero(), U256::zero())),
 			author: RwLock::new(Address::default()),
 			extra_data: RwLock::new(Vec::new()),
 			accounts: None,
 			spec: spec,
+			work_poster: None,
 		}
 	}

 	/// Creates new instance of miner
 	pub fn new(options: MinerOptions, spec: Spec, accounts: Option<Arc<AccountProvider>>) -> Arc<Miner> {
+		let work_poster = if !options.new_work_notify.is_empty() { Some(WorkPoster::new(&options.new_work_notify)) } else { None };
 		Arc::new(Miner {
 			transaction_queue: Mutex::new(TransactionQueue::with_limits(options.tx_queue_size, options.tx_gas_limit)),
-			sealing_enabled: AtomicBool::new(options.force_sealing),
-			options: options,
+			sealing_enabled: AtomicBool::new(options.force_sealing || !options.new_work_notify.is_empty()),
+			next_allowed_reseal: Mutex::new(Instant::now()),
 			sealing_block_last_request: Mutex::new(0),
-			sealing_work: Mutex::new(UsingQueue::new(5)),
+			sealing_work: Mutex::new(UsingQueue::new(options.work_queue_size)),
 			gas_range_target: RwLock::new((U256::zero(), U256::zero())),
 			author: RwLock::new(Address::default()),
 			extra_data: RwLock::new(Vec::new()),
+			options: options,
 			accounts: accounts,
 			spec: spec,
+			work_poster: work_poster,
 		})
 	}

@ -126,15 +148,20 @@ impl Miner {
 		self.spec.engine.deref()
 	}

+	fn forced_sealing(&self) -> bool {
+		self.options.force_sealing || !self.options.new_work_notify.is_empty()
+	}
+
 	/// Prepares new block for sealing including top transactions from queue.
 	#[cfg_attr(feature="dev", allow(match_same_arms))]
 	#[cfg_attr(feature="dev", allow(cyclomatic_complexity))]
 	fn prepare_sealing(&self, chain: &MiningBlockChainClient) {
 		trace!(target: "miner", "prepare_sealing: entering");

-		let (transactions, mut open_block) = {
+		let (transactions, mut open_block, last_work_hash) = {
 			let transactions = {self.transaction_queue.lock().unwrap().top_transactions()};
 			let mut sealing_work = self.sealing_work.lock().unwrap();
+			let last_work_hash = sealing_work.peek_last_ref().map(|pb| pb.block().fields().header.hash());
 			let best_hash = chain.best_block_header().sha3();
 /*
 			// check to see if last ClosedBlock in would_seals is actually same parent block.
@ -161,7 +188,7 @@ impl Miner {
 					)
 				}
 			};
-			(transactions, open_block)
+			(transactions, open_block, last_work_hash)
 		};

 		let mut invalid_transactions = HashSet::new();
@ -227,13 +254,23 @@ impl Miner {
 			}
 		}

+		let work = {
 			let mut sealing_work = self.sealing_work.lock().unwrap();
-		if sealing_work.peek_last_ref().map_or(true, |pb| pb.block().fields().header.hash() != block.block().fields().header.hash()) {
+			trace!(target: "miner", "Checking whether we need to reseal: last={:?}, this={:?}", last_work_hash, block.block().fields().header.hash());
+			let work = if last_work_hash.map_or(true, |h| h != block.block().fields().header.hash()) {
 				trace!(target: "miner", "Pushing a new, refreshed or borrowed pending {}...", block.block().fields().header.hash());
+				let pow_hash = block.block().fields().header.hash();
+				let number = block.block().fields().header.number();
+				let difficulty = *block.block().fields().header.difficulty();
 				sealing_work.push(block);
-		}
-
+				Some((pow_hash, difficulty, number))
+			} else {
+				None
+			};
 			trace!(target: "miner", "prepare_sealing: leaving (last={:?})", sealing_work.peek_last_ref().map(|b| b.block().fields().header.hash()));
+			work
+		};
+		work.map(|(pow_hash, difficulty, number)| self.work_poster.as_ref().map(|ref p| p.notify(pow_hash, difficulty, number)));
 	}

 	fn update_gas_limit(&self, chain: &MiningBlockChainClient) {
@ -261,6 +298,9 @@ impl Miner {
 		// Return if
 		!have_work
 	}
+
+	/// Are we allowed to do a non-mandatory reseal?
+	fn tx_reseal_allowed(&self) -> bool { Instant::now() > *self.next_allowed_reseal.lock().unwrap() }
 }

 const SEALING_TIMEOUT_IN_BLOCKS : u64 = 5;
@ -431,7 +471,7 @@ impl MinerService for Miner {
 				.map(|tx| transaction_queue.add(tx, &fetch_account, TransactionOrigin::External))
 				.collect()
 		};
-		if !results.is_empty() && self.options.reseal_on_external_tx {
+		if !results.is_empty() && self.options.reseal_on_external_tx && 	self.tx_reseal_allowed() {
 			self.update_sealing(chain);
 		}
 		results
@ -466,7 +506,7 @@ impl MinerService for Miner {
 			import
 		};

-		if imported.is_ok() && self.options.reseal_on_own_tx {
+		if imported.is_ok() && self.options.reseal_on_own_tx && self.tx_reseal_allowed() {
 			// Make sure to do it after transaction is imported and lock is droped.
 			// We need to create pending block and enable sealing
 			let prepared = self.enable_and_prepare_sealing(chain);
@ -549,7 +589,7 @@ impl MinerService for Miner {
 			let current_no = chain.chain_info().best_block_number;
 			let has_local_transactions = self.transaction_queue.lock().unwrap().has_local_pending_transactions();
 			let last_request = *self.sealing_block_last_request.lock().unwrap();
-			let should_disable_sealing = !self.options.force_sealing
+			let should_disable_sealing = !self.forced_sealing()
 				&& !has_local_transactions
 				&& current_no > last_request
 				&& current_no - last_request > SEALING_TIMEOUT_IN_BLOCKS;
@ -559,6 +599,7 @@ impl MinerService for Miner {
 				self.sealing_enabled.store(false, atomic::Ordering::Relaxed);
 				self.sealing_work.lock().unwrap().reset();
 			} else {
+				*self.next_allowed_reseal.lock().unwrap() = Instant::now() + self.options.reseal_min_period;
 				self.prepare_sealing(chain);
 			}
 		}
@ -575,26 +616,22 @@ impl MinerService for Miner {
 	}

 	fn submit_seal(&self, chain: &MiningBlockChainClient, pow_hash: H256, seal: Vec<Bytes>) -> Result<(), Error> {
-		if let Some(b) = self.sealing_work.lock().unwrap().take_used_if(|b| &b.hash() == &pow_hash) {
-			match b.lock().try_seal(self.engine(), seal) {
-				Err(_) => {
-					info!(target: "miner", "Mined block rejected, PoW was invalid.");
+		let result = if let Some(b) = self.sealing_work.lock().unwrap().get_used_if(if self.options.enable_resubmission { GetAction::Clone } else { GetAction::Take }, |b| &b.hash() == &pow_hash) {
+			b.lock().try_seal(self.engine(), seal).or_else(|_| {
+				warn!(target: "miner", "Mined solution rejected: Invalid.");
 				Err(Error::PowInvalid)
-				}
-				Ok(sealed) => {
-					info!(target: "miner", "New block mined, hash: {}", sealed.header().hash());
-					// TODO: commit DB from `sealed.drain` and make a VerifiedBlock to skip running the transactions twice.
-					let b = sealed.rlp_bytes();
-					let h = b.sha3();
-					try!(chain.import_block(b));
-					info!("Block {} submitted and imported.", h);
-					Ok(())
-				}
-			}
+			})
 		} else {
-			info!(target: "miner", "Mined block rejected, PoW hash invalid or out of date.");
+			warn!(target: "miner", "Mined solution rejected: Block unknown or out of date.");
 			Err(Error::PowHashInvalid)
-		}
+		};
+		result.and_then(|sealed| {
+			let n = sealed.header().number();
+			let h = sealed.header().hash();
+			try!(chain.import_sealed_block(sealed));
+			info!(target: "miner", "Mined block imported OK. #{}: {}", paint(White.bold(), format!("{}", n)), paint(White.bold(), h.hex()));
+			Ok(())
+		})
 	}

 	fn chain_new_blocks(&self, chain: &MiningBlockChainClient, _imported: &[H256], _invalid: &[H256], enacted: &[H256], retracted: &[H256]) {
--- a/ethcore/src/miner/mod.rs
+++ b/ethcore/src/miner/mod.rs
@ -45,6 +45,7 @@
 mod miner;
 mod external;
 mod transaction_queue;
+mod work_notify;

 pub use self::transaction_queue::{TransactionQueue, AccountDetails, TransactionImportResult, TransactionOrigin};
 pub use self::miner::{Miner, MinerOptions, PendingSet};
--- a/ethcore/src/miner/work_notify.rs
+++ b/ethcore/src/miner/work_notify.rs
@ -0,0 +1,115 @@
+// 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/>.
+
+extern crate hyper;
+
+use hyper::header::ContentType;
+use hyper::method::Method;
+use hyper::client::{Request, Response, Client};
+use hyper::{Next};
+use hyper::net::HttpStream;
+use ethash::SeedHashCompute;
+use hyper::Url;
+use util::*;
+use ethereum::ethash::Ethash;
+
+pub struct WorkPoster {
+	urls: Vec<Url>,
+	client: Mutex<Client<PostHandler>>,
+	seed_compute: Mutex<SeedHashCompute>,
+}
+
+impl WorkPoster {
+	pub fn new(urls: &[String]) -> Self {
+		let urls = urls.into_iter().filter_map(|u| {
+			match Url::parse(&u) {
+				Ok(url) => Some(url),
+				Err(e) => {
+					warn!("Error parsing URL {} : {}", u, e);
+					None
+				}
+			}
+		}).collect();
+		let client = WorkPoster::create_client();
+		WorkPoster {
+			client: Mutex::new(client),
+			urls: urls,
+			seed_compute: Mutex::new(SeedHashCompute::new()),
+		}
+	}
+
+	fn create_client() -> Client<PostHandler> {
+		let client = Client::<PostHandler>::configure()
+			.keep_alive(true)
+			.build().expect("Error creating HTTP client") as Client<PostHandler>;
+		client
+	}
+
+	pub fn notify(&self, pow_hash: H256, difficulty: U256, number: u64) {
+		// TODO: move this to engine
+		let target = Ethash::difficulty_to_boundary(&difficulty);
+		let seed_hash = &self.seed_compute.lock().unwrap().get_seedhash(number);
+		let seed_hash = H256::from_slice(&seed_hash[..]);
+		let body = format!(r#"{{ "result": ["0x{}","0x{}","0x{}","0x{:x}"] }}"#,
+			pow_hash.hex(), seed_hash.hex(), target.hex(), number);
+		let mut client = self.client.lock().unwrap();
+		for u in &self.urls {
+			if let Err(e) = client.request(u.clone(), PostHandler { body: body.clone() }) {
+				warn!("Error sending HTTP notification to {} : {}, retrying", u, e);
+				// TODO: remove this once https://github.com/hyperium/hyper/issues/848 is fixed
+				*client = WorkPoster::create_client();
+				if let Err(e) = client.request(u.clone(), PostHandler { body: body.clone() }) {
+					warn!("Error sending HTTP notification to {} : {}", u, e);
+				}
+			}
+		}
+	}
+}
+
+struct PostHandler {
+	body: String,
+}
+
+impl hyper::client::Handler<HttpStream> for PostHandler {
+	fn on_request(&mut self, request: &mut Request) -> Next {
+		request.set_method(Method::Post);
+		request.headers_mut().set(ContentType::json());
+		Next::write()
+	}
+
+	fn on_request_writable(&mut self, encoder: &mut hyper::Encoder<HttpStream>) -> Next {
+		if let Err(e) = encoder.write_all(self.body.as_bytes()) {
+			trace!("Error posting work data: {}", e);
+		}
+		encoder.close();
+		Next::read()
+
+	}
+
+	fn on_response(&mut self, _response: Response) -> Next {
+		Next::end()
+	}
+
+	fn on_response_readable(&mut self, _decoder: &mut hyper::Decoder<HttpStream>) -> Next {
+        Next::end()
+	}
+
+    fn on_error(&mut self, err: hyper::Error) -> Next {
+		trace!("Error posting work data: {}", err);
+		Next::end()
+    }
+}
+
--- a/ethcore/src/service.rs
+++ b/ethcore/src/service.rs
@ -17,6 +17,7 @@
 //! Creates and registers client and network services.

 use util::*;
+use util::Colour::{Yellow, White};
 use util::panics::*;
 use spec::Spec;
 use error::*;
@ -36,6 +37,8 @@ pub enum SyncMessage {
 		retracted: Vec<H256>,
 		/// Hashes of blocks that are now included in cannonical chain
 		enacted: Vec<H256>,
+		/// Hashes of blocks that are sealed by this node
+		sealed: Vec<H256>,
 	},
 	/// Best Block Hash in chain has been changed
 	NewChainHead,
@ -69,8 +72,7 @@ impl ClientService {
 			try!(net_service.start());
 		}

-		info!("Starting {}", net_service.host_info());
-		info!("Configured for {} using {:?} engine", spec.name, spec.engine.name());
+		info!("Configured for {} using {} engine", paint(White.bold(), spec.name.clone()), paint(Yellow.bold(), spec.engine.name().to_owned()));
 		let client = try!(Client::new(config, spec, db_path, miner, net_service.io().channel()));
 		panic_handler.forward_from(client.deref());
 		let client_io = Arc::new(ClientIoHandler {
--- a/ethcore/src/state.rs
+++ b/ethcore/src/state.rs
@ -208,12 +208,17 @@ impl State {
 		self.require(a, false).set_storage(key, value)
 	}

-	/// Initialise the code of account `a` so that it is `value` for `key`.
+	/// Initialise the code of account `a` so that it is `code`.
 	/// NOTE: Account should have been created with `new_contract`.
 	pub fn init_code(&mut self, a: &Address, code: Bytes) {
 		self.require_or_from(a, true, || Account::new_contract(0.into(), self.account_start_nonce), |_|{}).init_code(code);
 	}

+	/// Reset the code of account `a` so that it is `code`.
+	pub fn reset_code(&mut self, a: &Address, code: Bytes) {
+		self.require_or_from(a, true, || Account::new_contract(0.into(), self.account_start_nonce), |_|{}).reset_code(code);
+	}	
+
 	/// Execute a given transaction.
 	/// This will change the state accordingly.
 	pub fn apply(&mut self, env_info: &EnvInfo, engine: &Engine, vm_factory: &EvmFactory, t: &SignedTransaction, tracing: bool) -> ApplyResult {
--- a/ethcore/src/tests/helpers.rs
+++ b/ethcore/src/tests/helpers.rs
@ -17,7 +17,7 @@
 use client::{BlockChainClient, Client, ClientConfig};
 use common::*;
 use spec::*;
-use block::{OpenBlock};
+use block::{OpenBlock, Drain};
 use blockchain::{BlockChain, Config as BlockChainConfig};
 use state::*;
 use evm::Schedule;
--- a/install-parity.sh
+++ b/install-parity.sh
@ -1,6 +1,6 @@
 #!/usr/bin/env bash

-PARITY_DEB_URL=https://github.com/ethcore/parity/releases/download/v1.2.0/parity_linux_1.2.0-0_amd64.deb
+PARITY_DEB_URL=https://github.com/ethcore/parity/releases/download/v1.2.1/parity_linux_1.2.1-0_amd64.deb


 function run_installer()
--- a/parity/cli.rs
+++ b/parity/cli.rs
@ -137,6 +137,13 @@ Sealing/Mining Options:
                           own - reseal only on a new local transaction;
                           ext - reseal only on a new external transaction;
                           all - reseal on all new transactions [default: all].
+  --reseal-min-period MS   Specify the minimum time between reseals from 
+                           incoming transactions. MS is time measured in
+                           milliseconds [default: 2000].
+  --work-queue-size ITEMS  Specify the number of historical work packages
+                           which are kept cached lest a solution is found for 
+                           them later. High values take more memory but result
+                           in fewer unusable solutions [default: 20].
  --tx-gas-limit GAS       Apply a limit of GAS as the maximum amount of gas
                           a single transaction may have for it to be mined.
  --relay-set SET          Set of transactions to relay. SET may be:
@ -162,6 +169,12 @@ Sealing/Mining Options:
                           more than 32 characters.
  --tx-queue-size LIMIT    Maximum amount of transactions in the queue (waiting
                           to be included in next block) [default: 1024].
+  --remove-solved          Move solved blocks from the work package queue
+                           instead of cloning them. This gives a slightly
+                           faster import speed, but means that extra solutions
+                           submitted for the same work package will go unused.
+  --notify-work URLS       URLs to which work package notifications are pushed.
+                           URLS should be a comma-delimited list of HTTP URLs.

 Footprint Options:
  --tracing BOOL           Indicates if full transaction tracing should be
@ -302,6 +315,9 @@ pub struct Args {
 	pub flag_no_token: bool,
 	pub flag_force_sealing: bool,
 	pub flag_reseal_on_txs: String,
+	pub flag_reseal_min_period: u64,
+	pub flag_work_queue_size: usize,
+	pub flag_remove_solved: bool,
 	pub flag_tx_gas_limit: Option<String>,
 	pub flag_relay_set: String,
 	pub flag_author: Option<String>,
@ -311,6 +327,7 @@ pub struct Args {
 	pub flag_gas_cap: String,
 	pub flag_extra_data: Option<String>,
 	pub flag_tx_queue_size: usize,
+	pub flag_notify_work: Option<String>,
 	pub flag_logging: Option<String>,
 	pub flag_version: bool,
 	pub flag_from: String,
--- a/parity/configuration.rs
+++ b/parity/configuration.rs
@ -16,6 +16,7 @@

 use std::env;
 use std::fs::File;
+use std::time::Duration;
 use std::io::{BufRead, BufReader};
 use std::net::{SocketAddr, IpAddr};
 use std::path::PathBuf;
@ -24,6 +25,7 @@ use docopt::Docopt;

 use die::*;
 use util::*;
+use util::log::Colour::*;
 use ethcore::account_provider::AccountProvider;
 use util::network_settings::NetworkSettings;
 use ethcore::client::{append_path, get_db_path, ClientConfig, DatabaseCompactionProfile, Switch, VMType};
@ -83,6 +85,10 @@ impl Configuration {
 		)
 	}

+	fn work_notify(&self) -> Vec<String> {
+		self.args.flag_notify_work.as_ref().map_or_else(Vec::new, |s| s.split(',').map(|s| s.to_owned()).collect())
+	}
+
 	pub fn miner_options(&self) -> MinerOptions {
 		let (own, ext) = match self.args.flag_reseal_on_txs.as_str() {
 			"none" => (false, false),
@ -92,6 +98,7 @@ impl Configuration {
 			x => die!("{}: Invalid value for --reseal option. Use --help for more information.", x)
 		};
 		MinerOptions {
+			new_work_notify: self.work_notify(),
 			force_sealing: self.args.flag_force_sealing,
 			reseal_on_external_tx: ext,
 			reseal_on_own_tx: own,
@ -103,6 +110,9 @@ impl Configuration {
 				"lenient" => PendingSet::SealingOrElseQueue,
 				x => die!("{}: Invalid value for --relay-set option. Use --help for more information.", x)
 			},
+			reseal_min_period: Duration::from_millis(self.args.flag_reseal_min_period),
+			work_queue_size: self.args.flag_work_queue_size,
+			enable_resubmission: !self.args.flag_remove_solved,
 		}
 	}

@ -172,7 +182,7 @@ impl Configuration {
 				let wei_per_usd: f32 = 1.0e18 / usd_per_eth;
 				let gas_per_tx: f32 = 21000.0;
 				let wei_per_gas: f32 = wei_per_usd * usd_per_tx / gas_per_tx;
-				info!("Using a conversion rate of Ξ1 = US${} ({} wei/gas)", usd_per_eth, wei_per_gas);
+				info!("Using a conversion rate of Ξ1 = {} ({} wei/gas)", paint(White.bold(), format!("US${}", usd_per_eth)), paint(Yellow.bold(), format!("{}", wei_per_gas)));
 				U256::from_dec_str(&format!("{:.0}", wei_per_gas)).unwrap()
 			}
 		}
--- a/parity/main.rs
+++ b/parity/main.rs
@ -80,7 +80,7 @@ use std::thread::sleep;
 use std::time::Duration;
 use rustc_serialize::hex::FromHex;
 use ctrlc::CtrlC;
-use util::{H256, ToPretty, NetworkConfiguration, PayloadInfo, Bytes, UtilError};
+use util::{H256, ToPretty, NetworkConfiguration, PayloadInfo, Bytes, UtilError, paint, Colour, version};
 use util::panics::{MayPanic, ForwardPanic, PanicHandler};
 use ethcore::client::{BlockID, BlockChainClient, ClientConfig, get_db_path, BlockImportError};
 use ethcore::error::{ImportError};
@ -184,10 +184,12 @@ fn execute_client(conf: Configuration, spec: Spec, client_config: ClientConfig)
 	let panic_handler = PanicHandler::new_in_arc();

 	// Setup logging
-	let logger = setup_log::setup_log(&conf.args.flag_logging);
+	let logger = setup_log::setup_log(&conf.args.flag_logging, conf.have_color());
 	// Raise fdlimit
 	unsafe { ::fdlimit::raise_fd_limit(); }

+	info!("Starting {}", paint(Colour::White.bold(), format!("{}", version())));
+
 	let net_settings = conf.net_settings(&spec);
 	let sync_config = conf.sync_config(&spec);

@ -320,6 +322,8 @@ fn execute_export(conf: Configuration) {
 	// Setup panic handler
 	let panic_handler = PanicHandler::new_in_arc();

+	// Setup logging
+	let _logger = setup_log::setup_log(&conf.args.flag_logging, conf.have_color());
 	// Raise fdlimit
 	unsafe { ::fdlimit::raise_fd_limit(); }

@ -392,6 +396,8 @@ fn execute_import(conf: Configuration) {
 	// Setup panic handler
 	let panic_handler = PanicHandler::new_in_arc();

+	// Setup logging
+	let _logger = setup_log::setup_log(&conf.args.flag_logging, conf.have_color());
 	// Raise fdlimit
 	unsafe { ::fdlimit::raise_fd_limit(); }

--- a/parity/setup_log.rs
+++ b/parity/setup_log.rs
@ -19,10 +19,10 @@ use std::env;
 use std::sync::Arc;
 use time;
 use env_logger::LogBuilder;
-use util::{RotatingLogger};
+use util::RotatingLogger;

 /// Sets up the logger
-pub fn setup_log(init: &Option<String>) -> Arc<RotatingLogger> {
+pub fn setup_log(init: &Option<String>, enable_color: bool) -> Arc<RotatingLogger> {
 	use rlog::*;

 	let mut levels = String::new();
@ -43,7 +43,7 @@ pub fn setup_log(init: &Option<String>) -> Arc<RotatingLogger> {
 		builder.parse(s);
 	}

-	let logs = Arc::new(RotatingLogger::new(levels));
+	let logs = Arc::new(RotatingLogger::new(levels, enable_color));
 	let logger = logs.clone();
 	let format = move |record: &LogRecord| {
 		let timestamp = time::strftime("%Y-%m-%d %H:%M:%S %Z", &time::now()).unwrap();
--- a/rpc/src/v1/impls/eth.rs
+++ b/rpc/src/v1/impls/eth.rs
@ -504,7 +504,7 @@ impl<C, S, M, EM> Eth for EthClient<C, S, M, EM> where
 					let pow_hash = b.hash();
 					let target = Ethash::difficulty_to_boundary(b.block().header().difficulty());
 					let seed_hash = &self.seed_compute.lock().unwrap().get_seedhash(b.block().header().number());
-					to_value(&(pow_hash, H256::from_slice(&seed_hash[..]), target))
+					to_value(&(pow_hash, H256::from_slice(&seed_hash[..]), target, &U256::from(b.block().header().number())))
 				}).unwrap_or(Err(Error::internal_error()))	// no work found.
 			},
 			_ => Err(Error::invalid_params())
--- a/rpc/src/v1/tests/eth.rs
+++ b/rpc/src/v1/tests/eth.rs
@ -17,6 +17,7 @@
 //! rpc integration tests.
 use std::sync::Arc;
 use std::str::FromStr;
+use std::time::Duration;

 use ethcore::client::{BlockChainClient, Client, ClientConfig};
 use ethcore::ids::BlockID;
@ -51,12 +52,16 @@ fn sync_provider() -> Arc<TestSyncProvider> {
 fn miner_service(spec: Spec, accounts: Arc<AccountProvider>) -> Arc<Miner> {
 	Miner::new(
 		MinerOptions {
+			new_work_notify: vec![],
 			force_sealing: true,
 			reseal_on_external_tx: true,
 			reseal_on_own_tx: true,
 			tx_queue_size: 1024,
 			tx_gas_limit: !U256::zero(),
 			pending_set: PendingSet::SealingOrElseQueue,
+			reseal_min_period: Duration::from_secs(0),
+			work_queue_size: 50,
+			enable_resubmission: true,
 		},
 		spec,
 		Some(accounts)
--- a/rpc/src/v1/tests/mocked/ethcore.rs
+++ b/rpc/src/v1/tests/mocked/ethcore.rs
@ -32,7 +32,7 @@ fn client_service() -> Arc<TestBlockChainClient> {
 }

 fn logger() -> Arc<RotatingLogger> {
-	Arc::new(RotatingLogger::new("rpc=trace".to_owned()))
+	Arc::new(RotatingLogger::new("rpc=trace".to_owned(), false))
 }

 fn settings() -> Arc<NetworkSettings> {
--- a/signer/src/authcode_store.rs
+++ b/signer/src/authcode_store.rs
@ -120,7 +120,7 @@ impl<T: TimeProvider> AuthCodes<T> {
 			.filter_map(|f| String::from_utf8(f.to_vec()).ok())
 			.collect::<Vec<String>>()
 			.join("-");
-		info!(target: "signer", "New authentication token generated.");
+		trace!(target: "signer", "New authentication token generated.");
 		self.codes.push(code);
 		Ok(readable_code)
 	}
--- a/sync/src/chain.rs
+++ b/sync/src/chain.rs
@ -1231,6 +1231,14 @@ impl ChainSync {
 		rlp_stream.out()
 	}

+	/// creates latest block rlp for the given client
+	fn create_new_block_rlp(chain: &BlockChainClient, hash: &H256) -> Bytes {
+		let mut rlp_stream = RlpStream::new_list(2);
+		rlp_stream.append_raw(&chain.block(BlockID::Hash(hash.clone())).expect("Block has just been sealed; qed"), 1);
+		rlp_stream.append(&chain.block_total_difficulty(BlockID::Hash(hash.clone())).expect("Block has just been sealed; qed."));
+		rlp_stream.out()
+	}
+
 	/// returns peer ids that have less blocks than our chain
 	fn get_lagging_peers(&mut self, chain_info: &BlockChainInfo, io: &SyncIo) -> Vec<(PeerId, BlockNumber)> {
 		let latest_hash = chain_info.best_block_hash;
@ -1250,7 +1258,6 @@ impl ChainSync {
 			.collect::<Vec<_>>()
 	}

-
 	fn select_lagging_peers(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo) -> Vec<(PeerId, BlockNumber)> {
 		use rand::Rng;
 		let mut lagging_peers = self.get_lagging_peers(chain_info, io);
@ -1263,13 +1270,24 @@ impl ChainSync {
 	}

 	/// propagates latest block to lagging peers
-	fn propagate_blocks(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo) -> usize {
-		let lucky_peers = self.select_lagging_peers(chain_info, io);
+	fn propagate_blocks(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo, sealed: &[H256]) -> usize {
+		let lucky_peers: Vec<_> = if sealed.is_empty() {
+			self.select_lagging_peers(chain_info, io).iter().map(|&(id, _)| id).collect()
+		} else {
+			self.peers.keys().cloned().collect()
+		};
 		trace!(target: "sync", "Sending NewBlocks to {:?}", lucky_peers);
 		let mut sent = 0;
-		for (peer_id, _) in lucky_peers {
+		for peer_id in lucky_peers {
+			if sealed.is_empty() {
 				let rlp =  ChainSync::create_latest_block_rlp(io.chain());
 				self.send_packet(io, peer_id, NEW_BLOCK_PACKET, rlp);
+			} else {
+				for h in sealed {
+					let rlp =  ChainSync::create_new_block_rlp(io.chain(), h);
+					self.send_packet(io, peer_id, NEW_BLOCK_PACKET, rlp);
+				}
+			}
 			self.peers.get_mut(&peer_id).unwrap().latest_hash = chain_info.best_block_hash.clone();
 			self.peers.get_mut(&peer_id).unwrap().latest_number = Some(chain_info.best_block_number);
 			sent += 1;
@ -1346,11 +1364,11 @@ impl ChainSync {
 		sent
 	}

-	fn propagate_latest_blocks(&mut self, io: &mut SyncIo) {
+	fn propagate_latest_blocks(&mut self, io: &mut SyncIo, sealed: &[H256]) {
 		let chain_info = io.chain().chain_info();
 		if (((chain_info.best_block_number as i64) - (self.last_sent_block_number as i64)).abs() as BlockNumber) < MAX_PEER_LAG_PROPAGATION {
 			let hashes = self.propagate_new_hashes(&chain_info, io);
-			let blocks = self.propagate_blocks(&chain_info, io);
+			let blocks = self.propagate_blocks(&chain_info, io, sealed);
 			if blocks != 0 || hashes != 0 {
 				trace!(target: "sync", "Sent latest {} blocks and {} hashes to peers.", blocks, hashes);
 			}
@ -1365,10 +1383,10 @@ impl ChainSync {
 	}

 	/// called when block is imported to chain, updates transactions queue and propagates the blocks
-	pub fn chain_new_blocks(&mut self, io: &mut SyncIo, _imported: &[H256], invalid: &[H256], _enacted: &[H256], _retracted: &[H256]) {
+	pub fn chain_new_blocks(&mut self, io: &mut SyncIo, _imported: &[H256], invalid: &[H256], _enacted: &[H256], _retracted: &[H256], sealed: &[H256]) {
 		if io.is_chain_queue_empty() {
 			// Propagate latests blocks
-			self.propagate_latest_blocks(io);
+			self.propagate_latest_blocks(io, sealed);
 		}
 		if !invalid.is_empty() {
 			trace!(target: "sync", "Bad blocks in the queue, restarting");
@ -1637,7 +1655,26 @@ mod tests {
 		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5), &client);
 		let chain_info = client.chain_info();
 		let mut io = TestIo::new(&mut client, &mut queue, None);
-		let peer_count = sync.propagate_blocks(&chain_info, &mut io);
+		let peer_count = sync.propagate_blocks(&chain_info, &mut io, &[]);
+
+		// 1 message should be send
+		assert_eq!(1, io.queue.len());
+		// 1 peer should be updated
+		assert_eq!(1, peer_count);
+		// NEW_BLOCK_PACKET
+		assert_eq!(0x07, io.queue[0].packet_id);
+	}
+
+	#[test]
+	fn sends_sealed_block() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(100, EachBlockWith::Uncle);
+		let mut queue = VecDeque::new();
+		let hash = client.block_hash(BlockID::Number(99)).unwrap();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5), &client);
+		let chain_info = client.chain_info();
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+		let peer_count = sync.propagate_blocks(&chain_info, &mut io, &[hash.clone()]);

 		// 1 message should be send
 		assert_eq!(1, io.queue.len());
@ -1761,7 +1798,7 @@ mod tests {
 		let chain_info = client.chain_info();
 		let mut io = TestIo::new(&mut client, &mut queue, None);

-		sync.propagate_blocks(&chain_info, &mut io);
+		sync.propagate_blocks(&chain_info, &mut io, &[]);

 		let data = &io.queue[0].data.clone();
 		let result = sync.on_peer_new_block(&mut io, 0, &UntrustedRlp::new(data));
@ -1794,7 +1831,7 @@ mod tests {
 			let mut queue = VecDeque::new();
 			let mut io = TestIo::new(&mut client, &mut queue, None);
 			io.chain.miner.chain_new_blocks(io.chain, &[], &[], &[], &good_blocks);
-			sync.chain_new_blocks(&mut io, &[], &[], &[], &good_blocks);
+			sync.chain_new_blocks(&mut io, &[], &[], &[], &good_blocks, &[]);
 			assert_eq!(io.chain.miner.status().transactions_in_future_queue, 0);
 			assert_eq!(io.chain.miner.status().transactions_in_pending_queue, 1);
 		}
@ -1808,7 +1845,7 @@ mod tests {
 			let mut queue = VecDeque::new();
 			let mut io = TestIo::new(&mut client, &mut queue, None);
 			io.chain.miner.chain_new_blocks(io.chain, &[], &[], &good_blocks, &retracted_blocks);
-			sync.chain_new_blocks(&mut io, &[], &[], &good_blocks, &retracted_blocks);
+			sync.chain_new_blocks(&mut io, &[], &[], &good_blocks, &retracted_blocks, &[]);
 		}

 		// then
@ -1833,10 +1870,10 @@ mod tests {
 		let mut io = TestIo::new(&mut client, &mut queue, None);

 		// when
-		sync.chain_new_blocks(&mut io, &[], &[], &[], &good_blocks);
+		sync.chain_new_blocks(&mut io, &[], &[], &[], &good_blocks, &[]);
 		assert_eq!(io.chain.miner.status().transactions_in_future_queue, 0);
 		assert_eq!(io.chain.miner.status().transactions_in_pending_queue, 0);
-		sync.chain_new_blocks(&mut io, &[], &[], &good_blocks, &retracted_blocks);
+		sync.chain_new_blocks(&mut io, &[], &[], &good_blocks, &retracted_blocks, &[]);

 		// then
 		let status = io.chain.miner.status();
--- a/sync/src/lib.rs
+++ b/sync/src/lib.rs
@ -196,9 +196,9 @@ impl NetworkProtocolHandler<SyncMessage> for EthSync {
 	#[cfg_attr(feature="dev", allow(single_match))]
 	fn message(&self, io: &NetworkContext<SyncMessage>, message: &SyncMessage) {
 		match *message {
-			SyncMessage::NewChainBlocks { ref imported, ref invalid, ref enacted, ref retracted } => {
+			SyncMessage::NewChainBlocks { ref imported, ref invalid, ref enacted, ref retracted, ref sealed } => {
 				let mut sync_io = NetSyncIo::new(io, self.chain.deref());
-				self.sync.write().unwrap().chain_new_blocks(&mut sync_io, imported, invalid, enacted, retracted);
+				self.sync.write().unwrap().chain_new_blocks(&mut sync_io, imported, invalid, enacted, retracted, sealed);
 			},
 			_ => {/* Ignore other messages */},
 		}
--- a/sync/src/tests/helpers.rs
+++ b/sync/src/tests/helpers.rs
@ -173,6 +173,6 @@ impl TestNet {

 	pub fn trigger_chain_new_blocks(&mut self, peer_id: usize) {
 		let mut peer = self.peer_mut(peer_id);
-		peer.sync.write().unwrap().chain_new_blocks(&mut TestIo::new(&mut peer.chain, &mut peer.queue, None), &[], &[], &[], &[]);
+		peer.sync.write().unwrap().chain_new_blocks(&mut TestIo::new(&mut peer.chain, &mut peer.queue, None), &[], &[], &[], &[], &[]);
 	}
 }
--- a/util/Cargo.toml
+++ b/util/Cargo.toml
@ -37,6 +37,7 @@ vergen = "0.1"
 target_info = "0.1"
 bigint = { path = "bigint" }
 chrono = "0.2"
+ansi_term = "0.7"

 [features]
 default = []
--- a/util/src/kvdb.rs
+++ b/util/src/kvdb.rs
@ -99,7 +99,7 @@ impl DatabaseConfig {
 		DatabaseConfig {
 			cache_size: Some(cache_size),
 			prefix_size: None,
-			max_open_files: -1,
+			max_open_files: 256,
 			compaction: CompactionProfile::default(),
 		}
 	}
@ -122,7 +122,7 @@ impl Default for DatabaseConfig {
 		DatabaseConfig {
 			cache_size: None,
 			prefix_size: None,
-			max_open_files: -1,
+			max_open_files: 256,
 			compaction: CompactionProfile::default(),
 		}
 	}
--- a/util/src/lib.rs
+++ b/util/src/lib.rs
@ -117,6 +117,7 @@ extern crate libc;
 extern crate target_info;
 extern crate bigint;
 extern crate chrono;
+extern crate ansi_term;

 pub mod standard;
 #[macro_use]
--- a/util/src/log.rs
+++ b/util/src/log.rs
@ -20,7 +20,21 @@ use std::env;
 use rlog::{LogLevelFilter};
 use env_logger::LogBuilder;
 use std::sync::{RwLock, RwLockReadGuard};
+use std::sync::atomic::{Ordering, AtomicBool};
 use arrayvec::ArrayVec;
+pub use ansi_term::{Colour, Style};
+
+lazy_static! {
+	static ref USE_COLOR: AtomicBool = AtomicBool::new(false);
+}
+
+/// Paint, using colour if desired.
+pub fn paint(c: Style, t: String) -> String {
+	match USE_COLOR.load(Ordering::Relaxed) {
+		true => format!("{}", c.paint(t)),
+		false => t,
+	}
+}

 lazy_static! {
 	static ref LOG_DUMMY: bool = {
@ -57,7 +71,8 @@ impl RotatingLogger {

 	/// Creates new `RotatingLogger` with given levels.
 	/// It does not enforce levels - it's just read only.
-	pub fn new(levels: String) -> Self {
+	pub fn new(levels: String, enable_color: bool) -> Self {
+		USE_COLOR.store(enable_color, Ordering::Relaxed);
 		RotatingLogger {
 			levels: levels,
 			logs: RwLock::new(ArrayVec::<[_; LOG_SIZE]>::new()),
@ -86,7 +101,7 @@ mod test {
 	use super::RotatingLogger;

 	fn logger() -> RotatingLogger {
-		RotatingLogger::new("test".to_owned())
+		RotatingLogger::new("test".to_owned(), false)
 	}

 	#[test]
--- a/util/src/network/host.rs
+++ b/util/src/network/host.rs
@ -32,6 +32,8 @@ use misc::version;
 use crypto::*;
 use sha3::Hashable;
 use rlp::*;
+use log::Colour::White;
+use log::paint;
 use network::session::{Session, SessionData};
 use error::*;
 use io::*;
@ -343,6 +345,7 @@ pub struct Host<Message> where Message: Send + Sync + Clone {
 	reserved_nodes: RwLock<HashSet<NodeId>>,
 	num_sessions: AtomicUsize,
 	stopping: AtomicBool,
+	first_time: AtomicBool,
 }

 impl<Message> Host<Message> where Message: Send + Sync + Clone {
@ -398,6 +401,7 @@ impl<Message> Host<Message> where Message: Send + Sync + Clone {
 			reserved_nodes: RwLock::new(HashSet::new()),
 			num_sessions: AtomicUsize::new(0),
 			stopping: AtomicBool::new(false),
+			first_time: AtomicBool::new(true),
 		};

 		for n in boot_nodes {
@ -533,7 +537,11 @@ impl<Message> Host<Message> where Message: Send + Sync + Clone {
 		};

 		self.info.write().unwrap().public_endpoint = Some(public_endpoint.clone());
-		info!("Public node URL: {}", self.external_url().unwrap());
+
+		if self.first_time.load(AtomicOrdering::Relaxed) {
+			info!("Public node URL: {}", paint(White.bold(), format!("{}", self.external_url().unwrap())));
+			self.first_time.store(false, AtomicOrdering::Relaxed);
+		}

 		// Initialize discovery.
 		let discovery = {
--- a/util/src/network/tests.rs
+++ b/util/src/network/tests.rs
@ -88,7 +88,7 @@ impl NetworkProtocolHandler<TestProtocolMessage> for TestProtocol {

 	/// Timer function called after a timeout created with `NetworkContext::timeout`.
 	fn timeout(&self, io: &NetworkContext<TestProtocolMessage>, timer: TimerToken) {
-		io.message(TestProtocolMessage { payload: 22 });
+		io.message(TestProtocolMessage { payload: 22 }).unwrap();
 		assert_eq!(timer, 0);
 		self.got_timeout.store(true, AtomicOrdering::Relaxed);
 	}
--- a/util/src/using_queue.rs
+++ b/util/src/using_queue.rs
@ -27,6 +27,14 @@ pub struct UsingQueue<T> where T: Clone {
 	max_size: usize,
 }

+/// Take an item or just clone it?
+pub enum GetAction {
+	/// Remove the item, faster but you can't get it back.
+	Take,
+	/// Clone the item, slower but you can get it again.
+	Clone,
+}
+
 impl<T> UsingQueue<T> where T: Clone {
 	/// Create a new struct with a maximum size of `max_size`.
 	pub fn new(max_size: usize) -> UsingQueue<T> {
@ -74,6 +82,20 @@ impl<T> UsingQueue<T> where T: Clone {
 		self.in_use.iter().position(|r| predicate(r)).map(|i| self.in_use.remove(i))
 	}

+	/// Returns `Some` item which is the first that `f` returns `true` with a reference to it
+	/// as a parameter or `None` if no such item exists in the queue.
+	pub fn clone_used_if<P>(&mut self, predicate: P) -> Option<T> where P: Fn(&T) -> bool {
+		self.in_use.iter().find(|r| predicate(r)).cloned()
+	}
+
+	/// Fork-function for `take_used_if` and `clone_used_if`.
+	pub fn get_used_if<P>(&mut self, action: GetAction, predicate: P) -> Option<T> where P: Fn(&T) -> bool {
+		match action {
+			GetAction::Take => self.take_used_if(predicate),
+			GetAction::Clone => self.clone_used_if(predicate),
+		}
+	}
+
 	/// Returns the most recently pushed block if `f` returns `true` with a reference to it as
 	/// a parameter, otherwise `None`.
 	/// Will not destroy a block if a reference to it has previously been returned by `use_last_ref`,
@ -94,18 +116,66 @@ impl<T> UsingQueue<T> where T: Clone {
 }

 #[test]
-fn should_find_when_pushed() {
+fn should_not_find_when_pushed() {
 	let mut q = UsingQueue::new(2);
 	q.push(1);
 	assert!(q.take_used_if(|i| i == &1).is_none());
 }

+#[test]
+fn should_not_find_when_pushed_with_clone() {
+	let mut q = UsingQueue::new(2);
+	q.push(1);
+	assert!(q.clone_used_if(|i| i == &1).is_none());
+}
+
 #[test]
 fn should_find_when_pushed_and_used() {
 	let mut q = UsingQueue::new(2);
 	q.push(1);
 	q.use_last_ref();
-	assert!(q.take_used_if(|i| i == &1).is_some());
+	assert!(q.take_used_if(|i| i == &1).unwrap() == 1);
+}
+
+#[test]
+fn should_have_same_semantics_for_get_take_clone() {
+	let mut q = UsingQueue::new(2);
+	q.push(1);
+	assert!(q.get_used_if(GetAction::Clone, |i| i == &1).is_none());
+	assert!(q.get_used_if(GetAction::Take, |i| i == &1).is_none());
+	q.use_last_ref();
+	assert!(q.get_used_if(GetAction::Clone, |i| i == &1).unwrap() == 1);
+	assert!(q.get_used_if(GetAction::Clone, |i| i == &1).unwrap() == 1);
+	assert!(q.get_used_if(GetAction::Take, |i| i == &1).unwrap() == 1);
+	assert!(q.get_used_if(GetAction::Clone, |i| i == &1).is_none());
+	assert!(q.get_used_if(GetAction::Take, |i| i == &1).is_none());
+}
+
+#[test]
+fn should_find_when_pushed_and_used_with_clone() {
+	let mut q = UsingQueue::new(2);
+	q.push(1);
+	q.use_last_ref();
+	assert!(q.clone_used_if(|i| i == &1).unwrap() == 1);
+}
+
+#[test]
+fn should_not_find_again_when_pushed_and_taken() {
+	let mut q = UsingQueue::new(2);
+	q.push(1);
+	q.use_last_ref();
+	assert!(q.take_used_if(|i| i == &1).unwrap() == 1);
+	assert!(q.clone_used_if(|i| i == &1).is_none());
+}
+
+#[test]
+fn should_find_again_when_pushed_and_cloned() {
+	let mut q = UsingQueue::new(2);
+	q.push(1);
+	q.use_last_ref();
+	assert!(q.clone_used_if(|i| i == &1).unwrap() == 1);
+	assert!(q.clone_used_if(|i| i == &1).unwrap() == 1);
+	assert!(q.take_used_if(|i| i == &1).unwrap() == 1);
 }

 #[test]