rpc: add debug_tranceBlockByHash, fix debug_traceBlock* crash on non-existing block (#743)

* Problem: Missing debug_tranceBlockByHash RPC method

Solution: (Fix #742) Add the missing method

* Problem: debug_traceBlockByNumber crashed when block height not found

Solution: (Fix #744) Fix memory reference error

* Run go fmt

* Revert comment on init.sh

* Apply suggestions from code review

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

* Update rpc/ethereum/backend/backend.go

* Update rpc/ethereum/backend/backend.go

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

rpc/ethereum/backend/backend.go

@@ -53,6 +53,7 @@ type Backend interface {
 	// Blockchain API
 	BlockNumber() (hexutil.Uint64, error)
 	GetTendermintBlockByNumber(blockNum types.BlockNumber) (*tmrpctypes.ResultBlock, error)
+	GetTendermintBlockByHash(blockHash common.Hash) (*tmrpctypes.ResultBlock, error)
 	GetBlockByNumber(blockNum types.BlockNumber, fullTx bool) (map[string]interface{}, error)
 	GetBlockByHash(hash common.Hash, fullTx bool) (map[string]interface{}, error)
 	BlockByNumber(blockNum types.BlockNumber) (*ethtypes.Block, error)
@@ -306,6 +307,21 @@ func (e *EVMBackend) GetTendermintBlockByNumber(blockNum types.BlockNumber) (*tm
 	return resBlock, nil
 }
 
+// GetTendermintBlockByHash returns a Tendermint format block by block number
+func (e *EVMBackend) GetTendermintBlockByHash(blockHash common.Hash) (*tmrpctypes.ResultBlock, error) {
+	resBlock, err := e.clientCtx.Client.BlockByHash(e.ctx, blockHash.Bytes())
+	if err != nil {
+		e.logger.Debug("tendermint client failed to get block", "blockHash", blockHash.Hex(), "error", err.Error())
+	}
+
+	if resBlock == nil || resBlock.Block == nil {
+		e.logger.Debug("GetBlockByNumber block not found", "blockHash", blockHash.Hex())
+		return nil, nil
+	}
+
+	return resBlock, nil
+}
+
 // BlockBloom query block bloom filter from block results
 func (e *EVMBackend) BlockBloom(height *int64) (ethtypes.Bloom, error) {
 	result, err := e.clientCtx.Client.BlockResults(e.ctx, height)

rpc/ethereum/namespaces/debug/api.go

@@ -167,12 +167,32 @@ func (a *API) TraceBlockByNumber(height rpctypes.BlockNumber, config *evmtypes.T
 	// Get Tendermint Block
 	resBlock, err := a.backend.GetTendermintBlockByNumber(height)
 	if err != nil {
+		a.logger.Debug("get block failed", "height", height, "error", err.Error())
 		return nil, err
 	}
 
 	return a.traceBlock(height, config, resBlock)
 }
 
+// TraceBlockByHash returns the structured logs created during the execution of
+// EVM and returns them as a JSON object.
+func (a *API) TraceBlockByHash(hash common.Hash, config *evmtypes.TraceConfig) ([]*evmtypes.TxTraceResult, error) {
+	a.logger.Debug("debug_traceBlockByHash", "hash", hash)
+	// Get Tendermint Block
+	resBlock, err := a.backend.GetTendermintBlockByHash(hash)
+	if err != nil {
+		a.logger.Debug("get block failed", "hash", hash.Hex(), "error", err.Error())
+		return nil, err
+	}
+
+	if resBlock == nil || resBlock.Block == nil {
+		a.logger.Debug("block not found", "hash", hash.Hex())
+		return nil, errors.New("block not found")
+	}
+
+	return a.traceBlock(rpctypes.BlockNumber(resBlock.Block.Height), config, resBlock)
+}
+
 // traceBlock configures a new tracer according to the provided configuration, and
 // executes all the transactions contained within. The return value will be one item
 // per transaction, dependent on the requested tracer.