hmy_blockNumber (#910)

internal/hmyapi/README.md

@@ -14,7 +14,7 @@
 ### BlockChain info related
 * [ ] hmy_gasPrice - return min-gas-price
 * [ ] hmy_estimateGas - calculating estimate gas using signed bytes
-* [ ] hmy_blockNumber - get latest block number
+* [x] hmy_blockNumber - get latest block number
 * [x] hmy_getBlockByHash - get block by block hash
 * [x] hmy_getBlockByNumber
 * [ ] hmy_getUncleByBlockHashAndIndex - get uncle by block hash and index number

internal/hmyapi/blockchain.go

@@ -78,3 +78,9 @@ func (s *PublicBlockChainAPI) GetBalance(ctx context.Context, address common.Add
 	}
 	return (*hexutil.Big)(state.GetBalance(address)), state.Error()
 }
+
+// BlockNumber returns the block number of the chain head.
+func (s *PublicBlockChainAPI) BlockNumber() hexutil.Uint64 {
+	header, _ := s.b.HeaderByNumber(context.Background(), rpc.LatestBlockNumber) // latest header should always be available
+	return hexutil.Uint64(header.Number.Uint64())
+}