Watch transactions pool (#10558)

adds `parity_watchTransactionsPool`

ethcore/src/lib.rs

@@ -74,6 +74,7 @@ extern crate ethcore_miner;
 extern crate ethereum_types;
 extern crate ethjson;
 extern crate ethkey;
+extern crate futures;
 extern crate hash_db;
 extern crate heapsize;
 extern crate itertools;

ethcore/src/miner/miner.rs

@@ -24,11 +24,12 @@ use bytes::Bytes;
 use call_contract::CallContract;
 use ethcore_miner::gas_pricer::GasPricer;
 use ethcore_miner::local_accounts::LocalAccounts;
-use ethcore_miner::pool::{self, TransactionQueue, VerifiedTransaction, QueueStatus, PrioritizationStrategy};
+use ethcore_miner::pool::{self, TransactionQueue, VerifiedTransaction, QueueStatus, PrioritizationStrategy, TxStatus};
 use ethcore_miner::service_transaction_checker::ServiceTransactionChecker;
 #[cfg(feature = "work-notify")]
 use ethcore_miner::work_notify::NotifyWork;
 use ethereum_types::{H256, U256, Address};
+use futures::sync::mpsc;
 use io::IoChannel;
 use miner::pool_client::{PoolClient, CachedNonceClient, NonceCache};
 use miner;
@@ -263,6 +264,13 @@ impl Miner {
 		self.transaction_queue.add_listener(f);
 	}
 
+	/// Set a callback to be notified
+	pub fn tx_pool_receiver(&self) -> mpsc::UnboundedReceiver<Arc<Vec<(H256, TxStatus)>>> {
+		let (sender, receiver) = mpsc::unbounded();
+		self.transaction_queue.add_tx_pool_listener(sender);
+		receiver
+	}
+
 	/// Creates new instance of miner Arc.
 	pub fn new<A: LocalAccounts + 'static>(
 		options: MinerOptions,