types: add RawMessage struct type

Author: zchee

types.go

@@ -5,6 +5,9 @@
 package jsonrpc2
 
 import (
+	"encoding/json"
+	"errors"
+	"io"
 	"strconv"
 
 	"github.com/francoispqt/gojay"
@@ -54,6 +57,53 @@ type Message struct {
 	JSONRPC string `json:"jsonrpc"`
 }
 
+// RawMessage is the same as json.RawMessage.
+type RawMessage struct {
+	*gojay.EmbeddedJSON
+}
+
+// Read implements io.Reader.
+func (m *RawMessage) Read(p []byte) (n int, err error) {
+	if len(p) == 0 || p == nil {
+		return 0, nil
+	}
+	if m == nil {
+		return 0, io.EOF
+	}
+
+	n = copy(p, *m.EmbeddedJSON)
+
+	return n, nil
+}
+
+// MarshalJSON implements json.Marshaler.
+//
+// MarshalJSON returns m as the JSON encoding of m.
+func (m RawMessage) MarshalJSON() ([]byte, error) {
+	if m.EmbeddedJSON == nil {
+		return []byte("null"), nil
+	}
+
+	return *m.EmbeddedJSON, nil
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+//
+// UnmarshalJSON sets *m to a copy of data.
+func (m *RawMessage) UnmarshalJSON(data []byte) error {
+	if m == nil {
+		return errors.New("json.RawMessage: UnmarshalJSON on nil pointer")
+	}
+
+	*m.EmbeddedJSON = append((*m.EmbeddedJSON)[0:0], data...)
+
+	return nil
+}
+
+var _ io.Reader = (*RawMessage)(nil)
+var _ json.Marshaler = (*RawMessage)(nil)
+var _ json.Unmarshaler = (*RawMessage)(nil)
+
 // Request is a request message to describe a request between the client and the server.
 //
 // Every processed request must send a response back to the sender of the request.
@@ -67,7 +117,7 @@ type Request struct {
 	Method string `json:"method"`
 
 	// The method's params.
-	Params *gojay.EmbeddedJSON `json:"params,omitempty"`
+	Params *RawMessage `json:"params,omitempty"`
 }
 
 // IsNotify returns true if this request is a notification.
@@ -91,7 +141,7 @@ type Response struct {
 
 	// The result of a request. This member is REQUIRED on success.
 	// This member MUST NOT exist if there was an error invoking the method.
-	Result *gojay.EmbeddedJSON `json:"result,omitempty"`
+	Result *RawMessage `json:"result,omitempty"`
 }
 
 // NotificationMessage is a notification message.
@@ -104,5 +154,5 @@ type NotificationMessage struct {
 	Method string `json:"method"`
 
 	// Params is the notification's params.
-	Params interface{} `json:"params,omitempty"`
+	Params *RawMessage `json:"params,omitempty"`
 }