Merge pull request #107 from LesnyRumcajs/master

fix: make resp result/error conformant to spec

Author: magik6k

Diff for: handler.go

@@ -104,10 +104,30 @@ func (e *respError) val(errors *Errors) reflect.Value {
 }
 
 type response struct {
-	Jsonrpc string      `json:"jsonrpc"`
-	Result  interface{} `json:"result,omitempty"`
-	ID      interface{} `json:"id"`
-	Error   *respError  `json:"error,omitempty"`
+	Jsonrpc string
+	Result  interface{}
+	ID      interface{}
+	Error   *respError
+}
+
+func (r response) MarshalJSON() ([]byte, error) {
+	// Custom marshal logic as per JSON-RPC 2.0 spec:
+	// > `result`:
+	// > This member is REQUIRED on success.
+	// > This member MUST NOT exist if there was an error invoking the method.
+	//
+	// > `error`:
+	// > This member is REQUIRED on error.
+	// > This member MUST NOT exist if there was no error triggered during invocation.
+	data := make(map[string]interface{})
+	data["jsonrpc"] = r.Jsonrpc
+	data["id"] = r.ID
+	if r.Error != nil {
+		data["error"] = r.Error
+	} else {
+		data["result"] = r.Result
+	}
+	return json.Marshal(data)
 }
 
 type handler struct {

Diff for: rpc_test.go

@@ -127,16 +127,16 @@ func TestRawRequests(t *testing.T) {
 		}
 	}
 
-	t.Run("inc", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Inc", "params": [], "id": 1}`, `{"jsonrpc":"2.0","id":1}`, 1, 200))
-	t.Run("inc-null", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Inc", "params": null, "id": 1}`, `{"jsonrpc":"2.0","id":1}`, 1, 200))
-	t.Run("inc-noparam", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Inc", "id": 2}`, `{"jsonrpc":"2.0","id":2}`, 1, 200))
-	t.Run("add", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [10], "id": 4}`, `{"jsonrpc":"2.0","id":4}`, 10, 200))
+	t.Run("inc", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Inc", "params": [], "id": 1}`, `{"jsonrpc":"2.0","id":1,"result":null}`, 1, 200))
+	t.Run("inc-null", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Inc", "params": null, "id": 1}`, `{"jsonrpc":"2.0","id":1,"result":null}`, 1, 200))
+	t.Run("inc-noparam", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Inc", "id": 2}`, `{"jsonrpc":"2.0","id":2,"result":null}`, 1, 200))
+	t.Run("add", tc(`{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [10], "id": 4}`, `{"jsonrpc":"2.0","id":4,"result":null}`, 10, 200))
 	// Batch requests
 	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 5}`, `{"jsonrpc":"2.0","id":null,"error":{"code":-32700,"message":"Parse error"}}`, 0, 500))
-	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 6}]`, `[{"jsonrpc":"2.0","id":6}]`, 123, 200))
-	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 7},{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [-122], "id": 8}]`, `[{"jsonrpc":"2.0","id":7},{"jsonrpc":"2.0","id":8}]`, 1, 200))
-	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 9},{"jsonrpc": "2.0", "params": [-122], "id": 10}]`, `[{"jsonrpc":"2.0","id":9},{"error":{"code":-32601,"message":"method '' not found"},"id":10,"jsonrpc":"2.0"}]`, 123, 200))
-	t.Run("add", tc(`     [{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [-1], "id": 11}]   `, `[{"jsonrpc":"2.0","id":11}]`, -1, 200))
+	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 6}]`, `[{"jsonrpc":"2.0","id":6,"result":null}]`, 123, 200))
+	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 7},{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [-122], "id": 8}]`, `[{"jsonrpc":"2.0","id":7,"result":null},{"jsonrpc":"2.0","id":8,"result":null}]`, 1, 200))
+	t.Run("add", tc(`[{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [123], "id": 9},{"jsonrpc": "2.0", "params": [-122], "id": 10}]`, `[{"jsonrpc":"2.0","id":9,"result":null},{"error":{"code":-32601,"message":"method '' not found"},"id":10,"jsonrpc":"2.0"}]`, 123, 200))
+	t.Run("add", tc(`     [{"jsonrpc": "2.0", "method": "SimpleServerHandler.Add", "params": [-1], "id": 11}]   `, `[{"jsonrpc":"2.0","id":11,"result":null}]`, -1, 200))
 	t.Run("add", tc(``, `{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"Invalid request"}}`, 0, 400))
 }