From f20f841514e612c3c6c4ad3fa69131fcf193e90d Mon Sep 17 00:00:00 2001
From: LEE Dongjun <redongjun@gmail.com>
Date: Wed, 4 Jul 2018 16:54:32 +0900
Subject: [PATCH] Add getBestBlockId RPC method

---
 rpc/src/v1/impls/chain.rs  | 9 ++++++++-
 rpc/src/v1/traits/chain.rs | 6 +++++-
 rpc/src/v1/types/block.rs  | 9 ++++++++-
 rpc/src/v1/types/mod.rs    | 1 +
 spec/JSON-RPC.md           | 8 ++++----
 5 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/rpc/src/v1/impls/chain.rs b/rpc/src/v1/impls/chain.rs
index 3a3bd97f44..14582b9407 100644
--- a/rpc/src/v1/impls/chain.rs
+++ b/rpc/src/v1/impls/chain.rs
@@ -27,7 +27,7 @@ use jsonrpc_core::Result;
 
 use super::super::errors;
 use super::super::traits::Chain;
-use super::super::types::{Block, Bytes, Parcel};
+use super::super::types::{Block, BlockNumberAndHash, Bytes, Parcel};
 
 pub struct ChainClient {
     client: Arc<Client>,
@@ -110,6 +110,13 @@ impl Chain for ChainClient {
         Ok(self.client.chain_info().best_block_number)
     }
 
+    fn get_best_block_id(&self) -> Result<BlockNumberAndHash> {
+        Ok(BlockNumberAndHash {
+            number: self.client.chain_info().best_block_number,
+            hash: self.client.chain_info().best_block_hash,
+        })
+    }
+
     fn get_block_hash(&self, block_number: u64) -> Result<Option<H256>> {
         Ok(self.client.block_hash(BlockId::Number(block_number)))
     }
diff --git a/rpc/src/v1/traits/chain.rs b/rpc/src/v1/traits/chain.rs
index c56af26c06..2cc8a59c3d 100644
--- a/rpc/src/v1/traits/chain.rs
+++ b/rpc/src/v1/traits/chain.rs
@@ -19,7 +19,7 @@ use ctypes::{H160, H256, Public, U256};
 
 use jsonrpc_core::Result;
 
-use super::super::types::{Block, Bytes, Parcel};
+use super::super::types::{Block, BlockNumberAndHash, Bytes, Parcel};
 
 build_rpc_trait! {
     pub trait Chain {
@@ -63,6 +63,10 @@ build_rpc_trait! {
         # [rpc(name = "chain_getBestBlockNumber")]
         fn get_best_block_number(&self) -> Result<BlockNumber>;
 
+        /// Gets the number and the hash of the best block.
+        # [rpc(name = "chain_getBestBlockId")]
+        fn get_best_block_id(&self) -> Result<BlockNumberAndHash>;
+
         /// Gets the hash of the block with given number.
         # [rpc(name = "chain_getBlockHash")]
         fn get_block_hash(&self, u64) -> Result<Option<H256>>;
diff --git a/rpc/src/v1/types/block.rs b/rpc/src/v1/types/block.rs
index 37f7dca1f4..cd2dd12c02 100644
--- a/rpc/src/v1/types/block.rs
+++ b/rpc/src/v1/types/block.rs
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-use ccore::Block as CoreBlock;
+use ccore::{Block as CoreBlock, BlockNumber};
 use ctypes::{H160, H256, U256};
 
 use super::Parcel;
@@ -84,3 +84,10 @@ impl From<CoreBlock> for Block {
         }
     }
 }
+
+#[derive(Debug, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct BlockNumberAndHash {
+    pub number: BlockNumber,
+    pub hash: H256,
+}
diff --git a/rpc/src/v1/types/mod.rs b/rpc/src/v1/types/mod.rs
index 4a505a053b..222e2f7c7b 100644
--- a/rpc/src/v1/types/mod.rs
+++ b/rpc/src/v1/types/mod.rs
@@ -20,6 +20,7 @@ mod parcel;
 mod work;
 
 pub use self::block::Block;
+pub use self::block::BlockNumberAndHash;
 pub use self::bytes::Bytes;
 pub use self::parcel::Parcel;
 pub use self::work::Work;
diff --git a/spec/JSON-RPC.md b/spec/JSON-RPC.md
index 7a5a5d78ed..4098a7863f 100644
--- a/spec/JSON-RPC.md
+++ b/spec/JSON-RPC.md
@@ -71,7 +71,7 @@ In the current version, it's only supported through HTTP.
  * [ping](#ping)
 ***
  * [chain_getBestBlockNumber](#chain_getbestblocknumber)
- * [chain_getBestBlockId](#chain_getbestblockid) (not implemented yet)
+ * [chain_getBestBlockId](#chain_getbestblockid)
  * [chain_getBlockHash](#chain_getblockhash)
  * [chain_getBlockByHash](#chain_getblockbyhash)
  * [chain_sendSignedParcel](#chain_sendsignedparcel)
@@ -139,7 +139,7 @@ Response Example
 ```
 
 ## chain_getBestBlockId
-(not implemented yet) Gets the number and the hash of the best block.
+Gets the number and the hash of the best block.
 
 Params: No parameters
 
@@ -155,7 +155,7 @@ Request Example
 
 Response Example
 ```
-{"jsonrpc":"2.0","result":{"number":1,"hash":"0x56642f04d519ae3262c7ba6facf1c5b11450ebaeb7955337cfbc45420d573077"},"id":null}
+{"jsonrpc":"2.0","result":{"hash":"0x56642f04d519ae3262c7ba6facf1c5b11450ebaeb7955337cfbc45420d573077","number":1},"id":null}
 ```
 
 ## chain_getBlockHash
@@ -646,4 +646,4 @@ Request Example
 Response Example
 ```
 {"jsonrpc":"2.0","result":["0x20d560025f3a1c6675cb32384355ae05b224a3473ae17d3d15b6aa164af7d717","0xf84541a053000000000000002ab33f741ba153ff1ffdf1107845828637c864d5360e4932a00000000000000000000000000000000000000000000000000000000000000000c06f"],"id":null}
-```
\ No newline at end of file
+```