fix dubbo option mapTo throwing unexpected errors (apache#177)

Former-commit-id: b5ed650

pkg/client/dubbo/dubbo.go

@@ -139,13 +139,13 @@ func (dc *Client) Close() error {
 // Call invoke service
 func (dc *Client) Call(req *client.Request) (res interface{}, err error) {
 	values, err := dc.genericArgs(req)
+	if err != nil {
+		return nil, err
+	}
 	val, ok := values.(*dubboTarget)
 	if !ok {
 		return nil, errors.New("map parameters failed")
 	}
-	if err != nil {
-		return nil, err
-	}
 
 	dm := req.API.Method.IntegrationRequest
 	method := dm.Method

pkg/client/dubbo/dubbo_test.go

@@ -176,6 +176,39 @@ func TestMappingParams(t *testing.T) {
 	assert.Equal(t, params.(*dubboTarget).Values[2], "1234567")
 	assert.Equal(t, params.(*dubboTarget).Values[3], "male")
 	assert.Equal(t, params.(*dubboTarget).Values[4], "Joe")
+
+	r, _ = http.NewRequest("POST", "/mock/test?id=12345&age=19", bytes.NewReader([]byte(`{"sex": "male", "name":{"firstName": "Joe", "lastName": "Biden"}}`)))
+	api = mock.GetMockAPI(config.MethodGet, "/mock/test")
+	api.IntegrationRequest.MappingParams = []config.MappingParam{
+		{
+			Name:  "queryStrings.id",
+			MapTo: "opt.method",
+		},
+		{
+			Name:  "queryStrings.age",
+			MapTo: "opt.application",
+		},
+		{
+			Name:  "headers.Auth",
+			MapTo: "opt.group",
+		},
+		{
+			Name:  "requestBody.sex",
+			MapTo: "opt.values",
+		},
+		{
+			Name:  "requestBody.name.firstName",
+			MapTo: "opt.interface",
+		},
+	}
+	r.Header.Set("Auth", "1234567")
+	req = client.NewReq(context.TODO(), r, api)
+	_, err = dClient.MapParams(req)
+	assert.Nil(t, err)
+	assert.Equal(t, req.API.Method.IntegrationRequest.DubboBackendConfig.ApplicationName, "19")
+	assert.Equal(t, req.API.Method.IntegrationRequest.DubboBackendConfig.Group, "1234567")
+	assert.Equal(t, req.API.Method.IntegrationRequest.DubboBackendConfig.Interface, "Joe")
+	assert.Equal(t, req.API.Method.IntegrationRequest.DubboBackendConfig.Method, "12345")
 }
 
 func TestBuildOption(t *testing.T) {

pkg/client/dubbo/mapper.go

@@ -92,7 +92,7 @@ func (qm queryStringsMapper) Map(mp config.MappingParam, c *client.Request, targ
 		return err
 	}
 	pos, err := strconv.Atoi(mp.MapTo)
-	if err != nil {
+	if err != nil && option == nil {
 		return errors.Errorf("Parameter mapping %v incorrect", mp)
 	}
 	qValue := queryValues.Get(key[0])
@@ -113,7 +113,7 @@ func (hm headerMapper) Map(mp config.MappingParam, c *client.Request, target int
 	}
 	_, key, err := client.ParseMapSource(mp.Name)
 	pos, err := strconv.Atoi(mp.MapTo)
-	if err != nil {
+	if err != nil && option == nil {
 		return errors.Errorf("Parameter mapping %+v incorrect", mp)
 	}
 	header := c.IngressRequest.Header.Get(key[0])
@@ -138,7 +138,7 @@ func (bm bodyMapper) Map(mp config.MappingParam, c *client.Request, target inter
 		return err
 	}
 	pos, err := strconv.Atoi(mp.MapTo)
-	if err != nil {
+	if err != nil && option == nil {
 		return errors.Errorf("Parameter mapping %v incorrect, parameters for Dubbo backend must be mapped to an int to represent position", mp)
 	}
 
@@ -174,7 +174,7 @@ func (um uriMapper) Map(mp config.MappingParam, c *client.Request, target interf
 		return err
 	}
 	pos, err := strconv.Atoi(mp.MapTo)
-	if err != nil {
+	if err != nil && option == nil {
 		return errors.Errorf("Parameter mapping %v incorrect", mp)
 	}
 	uriValues := router.GetURIParams(&c.API, *c.IngressRequest.URL)