adding examples.

milogo.go

@@ -19,8 +19,8 @@ func (w *customResponseWriter) Write(data []byte) (int, error) {
 	return w.body.Write(data)
 }
 
-func Milogo() gin.HandlerFunc {
-	config := pkg.DefaultConfig()
+func Milogo(configOptions ...pkg.ConfigOption) gin.HandlerFunc {
+	config := pkg.DefaultConfig(configOptions...)
 
 	return func(c *gin.Context) {
 		// Create a custom response writer
@@ -35,6 +35,8 @@ func Milogo() gin.HandlerFunc {
 			var jsonData interface{}
 			if err := json.Unmarshal(writer.body.Bytes(), &jsonData); err == nil {
 				fields := c.Query(config.QueryParamField)
+
+				// TODO wrapper
 				if partialResponseFields, errParsing := config.Parser.Parse(fields); errParsing == nil &&
 					pkg.Filter(jsonData, partialResponseFields) == nil {
 					modifiedBody, err := json.Marshal(jsonData)

milogo_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"github.com/gin-gonic/gin"
+	"github.com/manuelarte/milogo/pkg"
 	"github.com/stretchr/testify/assert"
 	"net/http"
 	"net/http/httptest"
@@ -39,13 +40,23 @@ func TestEchoRoute(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			router := setupRouter()
+			url := "/echo"
+			router.POST(url, func(c *gin.Context) {
+				var body map[string]interface{}
+				err := c.BindJSON(&body)
+				if err != nil {
+					c.Status(400)
+
+					return
+				}
+				c.JSON(200, body)
+			})
 
 			w := httptest.NewRecorder()
 			out, err := json.Marshal(test.body)
 			if err != nil {
 				t.Fatal(err)
 			}
-			url := "/echo"
 			if test.fields != "" {
 				url += "?fields=" + test.fields
 			}
@@ -172,20 +183,64 @@ func TestArrayRoute(t *testing.T) {
 	}
 }
 
-func setupRouter() *gin.Engine {
+func TestEchoWrapRoute(t *testing.T) {
+	t.Parallel()
+
+	tests := map[string]struct {
+		body     interface{}
+		fields   string
+		expected string
+	}{
+		"no query param fields": {
+			body:     map[string]interface{}{"name": "Manuel", "age": 99},
+			fields:   "",
+			expected: `{"data":{"name":"Manuel","age":99}}`,
+		},
+		"query param fields, 1/2": {
+			body:     map[string]interface{}{"name": "Manuel", "age": 99},
+			fields:   "name",
+			expected: `{"data":{"name":"Manuel"}}`,
+		},
+		"query param fields, 2/2": {
+			body:     map[string]interface{}{"name": "Manuel", "age": 99},
+			fields:   "name,age",
+			expected: `{"data":{"name":"Manuel","age":99}}`,
+		},
+	}
+	for name, test := range tests {
+		name, test := name, test
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			milogoOption, _ := pkg.WithWrapField("data")
+			url := "/echo-wrap"
+			router := setupRouter(milogoOption)
+			router.POST(url, func(c *gin.Context) {
+				type Response struct {
+					Data interface{} `json:"data"`
+				}
+				c.JSON(200, Response{Data: test.body})
+			})
+
+			w := httptest.NewRecorder()
+			out, err := json.Marshal(test.body)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if test.fields != "" {
+				url += "?fields=" + test.fields
+			}
+			req, _ := http.NewRequest("POST", url, bytes.NewBuffer(out))
+			router.ServeHTTP(w, req)
+
+			assert.Equal(t, 200, w.Code)
+			assert.JSONEq(t, test.expected, w.Body.String())
+		})
+	}
+}
+
+func setupRouter(configOptions ...pkg.ConfigOption) *gin.Engine {
 	r := gin.Default()
-	r.Use(Milogo())
-
-	r.POST("/echo", func(c *gin.Context) {
-		var body map[string]interface{}
-		err := c.BindJSON(&body)
-		if err != nil {
-			c.Status(400)
-
-			return
-		}
-		c.JSON(200, body)
-	})
+	r.Use(Milogo(configOptions...))
 
 	return r
 }

pkg/model.go

@@ -2,12 +2,27 @@ package pkg
 
 type Config struct {
 	QueryParamField string
+	WrapperField    string
 	Parser          Parser
 }
 
-func DefaultConfig() Config {
-	return Config{
+func DefaultConfig(configOptions ...ConfigOption) Config {
+	c := Config{
 		QueryParamField: "fields",
 		Parser:          NewParser(),
 	}
+	for _, co := range configOptions {
+		co(c)
+	}
+
+	return c
+}
+
+type ConfigOption func(c Config)
+
+func WithWrapField(wrapperField string) (ConfigOption, error) {
+	// validate wrapper field is not several words, but only one and alphanumeric
+	return func(c Config) {
+		c.WrapperField = wrapperField
+	}, nil
 }