Fix json decoder

replace std json to json Iter

Fix CI failure

go.mod

@@ -29,6 +29,7 @@ require (
 	github.com/hashicorp/go-version v1.2.0
 	github.com/hashicorp/golang-lru v0.5.4
 	github.com/ipfs/go-ds-badger v0.2.4
+	github.com/json-iterator/go v1.1.10
 	github.com/libp2p/go-libp2p v0.13.0
 	github.com/libp2p/go-libp2p-core v0.8.0
 	github.com/libp2p/go-libp2p-crypto v0.1.0

rpc/types.go

@@ -19,6 +19,7 @@ import (
 	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/numeric"
 	"github.com/harmony-one/harmony/shard"
+	jsoniter "github.com/json-iterator/go"
 )
 
 // CallArgs represents the arguments for a call.
@@ -101,11 +102,12 @@ type StructuredResponse = map[string]interface{}
 // NewStructuredResponse creates a structured response from the given input
 func NewStructuredResponse(input interface{}) (StructuredResponse, error) {
 	var objMap StructuredResponse
-	dat, err := json.Marshal(input)
+	var jsonIter = jsoniter.ConfigCompatibleWithStandardLibrary
+	dat, err := jsonIter.Marshal(input)
 	if err != nil {
 		return nil, err
 	}
-	d := json.NewDecoder(bytes.NewReader(dat))
+	d := jsonIter.NewDecoder(bytes.NewReader(dat))
 	d.UseNumber()
 	err = d.Decode(&objMap)
 	if err != nil {