Implement block_by_number Runtime API

frame/ethereum/src/lib.rs

@@ -33,7 +33,7 @@ use sp_runtime::{
 use sha3::{Digest, Keccak256};
 
 pub use frontier_rpc_primitives::TransactionStatus;
-pub use ethereum::{Transaction, Log};
+pub use ethereum::{Transaction, Log, Block};
 
 /// A type alias for the balance type from this pallet's point of view.
 pub type BalanceOf<T> = <T as pallet_balances::Trait>::Balance;
@@ -226,6 +226,16 @@ impl<T: Trait> Module<T> {
 		TransactionStatuses::get(hash)
 	}
 
+	pub fn block_by_number(number: T::BlockNumber) -> Option<ethereum::Block> {
+		if <BlockNumbers<T>>::contains_key(number) {
+			let hash = <BlockNumbers<T>>::get(number);
+			if let Some((block, _receipt)) = BlocksAndReceipts::get(hash) {
+				return Some(block)
+			}
+		}
+		None
+	}
+
 	/// Execute an Ethereum transaction, ignoring transaction signatures.
 	pub fn execute(source: H160, transaction: ethereum::Transaction) {
 		let transaction_hash = H256::from_slice(

rpc/core/src/eth.rs

@@ -85,7 +85,7 @@ pub trait EthApi {
 
 	/// Returns block with given number.
 	#[rpc(name = "eth_getBlockByNumber")]
-	fn block_by_number(&self, _: BlockNumber, _: bool) -> BoxFuture<Option<RichBlock>>;
+	fn block_by_number(&self, _: BlockNumber, _: bool) -> Result<Option<RichBlock>>;
 
 	/// Returns the number of transactions sent from given address at given time (block number).
 	#[rpc(name = "eth_getTransactionCount")]

rpc/primitives/src/lib.rs

@@ -17,7 +17,7 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
 use sp_core::{H160, H256, U256};
-use ethereum::Log;
+use ethereum::{Log, Block as EthereumBlock};
 use ethereum_types::Bloom;
 use codec::{Encode, Decode};
 use sp_std::vec::Vec;
@@ -42,6 +42,7 @@ sp_api::decl_runtime_apis! {
 		fn gas_price() -> U256;
 		fn account_code_at(address: H160) -> Vec<u8>;
 		fn author() -> H160;
+		fn block_by_number(number: u32) -> Option<EthereumBlock>;
 	}
 }
 

rpc/src/lib.rs

@@ -15,6 +15,7 @@
 // along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
 
 use std::{marker::PhantomData, sync::Arc};
+use std::collections::BTreeMap;
 use ethereum_types::{H160, H256, H64, U256, U64};
 use jsonrpc_core::{BoxFuture, Result, ErrorCode, Error, futures::future::{self, Future}};
 use futures::future::TryFutureExt;
@@ -30,7 +31,7 @@ use sp_runtime::traits::BlakeTwo256;
 use frontier_rpc_core::EthApi as EthApiT;
 use frontier_rpc_core::types::{
 	BlockNumber, Bytes, CallRequest, EthAccount, Filter, Index, Log, Receipt, RichBlock,
-	SyncStatus, Transaction, Work,
+	SyncStatus, Transaction, Work, Rich, Block, BlockTransactions
 };
 use frontier_rpc_primitives::{EthereumRuntimeApi, ConvertTransaction};
 
@@ -168,8 +169,53 @@ impl<B, C, SC, P, CT, BE> EthApiT for EthApi<B, C, SC, P, CT, BE> where
 		unimplemented!("block_by_hash");
 	}
 
-	fn block_by_number(&self, _: BlockNumber, _: bool) -> BoxFuture<Option<RichBlock>> {
-		unimplemented!("block_by_number");
+	fn block_by_number(&self, number: BlockNumber, _: bool) -> Result<Option<RichBlock>> {
+		let header = self.select_chain.best_chain()
+			.map_err(|_| internal_err("fetch header failed"))?;
+
+		let number_param: u32;
+
+		if let Some(block_number) = number.to_min_block_num() {
+			number_param = block_number.unique_saturated_into();
+		} else if number == BlockNumber::Latest {
+			number_param = header.number().clone().unique_saturated_into() as u32;
+		} else {
+			unimplemented!("only latest or block number are supported");
+		}
+
+		if let Ok(Some(block)) = self.client.runtime_api().block_by_number(
+			&BlockId::Hash(header.hash()), 
+			number_param) {
+			Ok(Some(Rich {
+				inner: Block {
+					hash: None, // TODO
+					parent_hash: block.header.parent_hash,
+					uncles_hash: H256::zero(), // TODO
+					author: H160::default(), // TODO
+					miner: H160::default(), // TODO
+					state_root: block.header.state_root,
+					transactions_root: block.header.transactions_root,
+					receipts_root: block.header.receipts_root,
+					number: Some(block.header.number),
+					gas_used: block.header.gas_used,
+					gas_limit: block.header.gas_limit,
+					extra_data: Bytes(vec![]), // TODO H256 to Vec<u8>
+					logs_bloom: Some(block.header.logs_bloom),
+					timestamp: U256::from(block.header.timestamp),
+					difficulty: block.header.difficulty,
+					total_difficulty: None, // TODO
+					seal_fields: vec![], // TODO
+					uncles: vec![], // TODO
+					// TODO expected struct `frontier_rpc_core::types::transaction::Transaction`, 
+					// found struct `ethereum::transaction::Transaction`
+					transactions: BlockTransactions::Full(vec![]),
+					size: None // TODO
+				},
+				extra_info: BTreeMap::new()
+			}))
+		} else {
+			Ok(None)
+		}
 	}
 
 	fn transaction_count(&self, address: H160, number: Option<BlockNumber>) -> Result<U256> {

template/runtime/src/lib.rs

@@ -58,6 +58,9 @@ pub use frame_support::{
 	},
 	StorageValue,
 };
+use ethereum::Block as EthereumBlock;
+
+
 #[cfg(any(feature = "std", test))]
 pub use sp_runtime::BuildStorage;
 pub use sp_runtime::{Perbill, Permill};
@@ -470,6 +473,10 @@ impl_runtime_apis! {
 				H160::zero()
 			}
 		}
+
+		fn block_by_number(number: u32) -> Option<EthereumBlock> {
+			<ethereum::Module<Runtime>>::block_by_number(number)
+		}
 	}
 
 	impl pallet_transaction_payment_rpc_runtime_api::TransactionPaymentApi<