Add a new RPC parity_submitWorkDetail similar eth_submitWork but return block hash (#9404)

* add a new RPC `eth_submitWorkDetail`similar `eth_submitWork`.

It has more details (block hash, error message, and more in future)
in its response and not only the `true` or `false`.

* move RPC submitWorkDetail from namespace eth_ to parity_

* remove SubmitDetailResult type; submitWorkDetail return a error when failed

* change error message of RPC error `cannot_submit_work`.

* remove double imported H256.

* put submit_work_detail into a helper to avoid the duplicate codes.

rpc/src/v1/helpers/errors.rs

@@ -35,6 +35,7 @@ mod codes {
 	pub const NO_AUTHOR: i64 = -32002;
 	pub const NO_NEW_WORK: i64 = -32003;
 	pub const NO_WORK_REQUIRED: i64 = -32004;
+	pub const CANNOT_SUBMIT_WORK: i64 = -32005;
 	pub const UNKNOWN_ERROR: i64 = -32009;
 	pub const TRANSACTION_ERROR: i64 = -32010;
 	pub const EXECUTION_ERROR: i64 = -32015;
@@ -197,6 +198,14 @@ pub fn no_work_required() -> Error {
 	}
 }
 
+pub fn cannot_submit_work(err: EthcoreError) -> Error {
+	Error {
+		code: ErrorCode::ServerError(codes::CANNOT_SUBMIT_WORK),
+		message: "Cannot submit work.".into(),
+		data: Some(Value::String(err.to_string())),
+	}
+}
+
 pub fn not_enough_data() -> Error {
 	Error {
 		code: ErrorCode::ServerError(codes::UNSUPPORTED_REQUEST),

rpc/src/v1/helpers/mod.rs

@@ -34,6 +34,7 @@ mod signer;
 mod signing_queue;
 mod subscribers;
 mod subscription_manager;
+mod work;
 
 pub use self::dispatch::{Dispatcher, FullDispatcher};
 pub use self::network_settings::NetworkSettings;
@@ -50,6 +51,7 @@ pub use self::signing_queue::{
 pub use self::signer::SignerService;
 pub use self::subscribers::Subscribers;
 pub use self::subscription_manager::GenericPollManager;
+pub use self::work::submit_work_detail;
 
 pub fn to_url(address: &Option<::Host>) -> Option<String> {
 	address.as_ref().map(|host| (**host).to_owned())

rpc/src/v1/helpers/work.rs

@@ -0,0 +1,47 @@
+// Copyright 2015-2018 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/>.
+
+//! Helpers for submit a POW work.
+
+use std::sync::Arc;
+
+use rlp;
+use ethcore::miner::{BlockChainClient, MinerService};
+use ethereum_types::{H64 as EthcoreH64, H256 as EthcoreH256};
+use jsonrpc_core::Error;
+use v1::types::{H64, H256};
+use v1::helpers::errors;
+
+// Submit a POW work and return the block's hash
+pub fn submit_work_detail<C: BlockChainClient, M: MinerService>(client: &Arc<C>, miner: &Arc<M>, nonce: H64, pow_hash: H256, mix_hash: H256) -> Result<H256, Error> {
+	// TODO [ToDr] Should disallow submissions in case of PoA?
+	let nonce: EthcoreH64 = nonce.into();
+	let pow_hash: EthcoreH256 = pow_hash.into();
+	let mix_hash: EthcoreH256 = mix_hash.into();
+	trace!(target: "miner", "submit_work_detail: Decoded: nonce={}, pow_hash={}, mix_hash={}", nonce, pow_hash, mix_hash);
+	let seal = vec![rlp::encode(&mix_hash).into_vec(), rlp::encode(&nonce).into_vec()];
+	let import = miner.submit_seal(pow_hash, seal)
+		.and_then(|block| client.import_sealed_block(block));
+	match import {
+		Ok(hash) => {
+			Ok(hash.into())
+		},
+		Err(err) => {
+			warn!(target: "miner", "Cannot submit work - {:?}.", err);
+			Err(errors::cannot_submit_work(err))
+		},
+	}
+}