feat: support form array in three notations (#4498)

Signed-off-by: kevin <wanjunfeng@gmail.com>

rest/httpx/requests_test.go

@@ -88,6 +88,36 @@ func TestParseFormArray(t *testing.T) {
 		}
 	})
 
+	t.Run("slice with empty", func(t *testing.T) {
+		var v struct {
+			Name []string `form:"name,optional"`
+		}
+
+		r, err := http.NewRequest(
+			http.MethodGet,
+			"/a",
+			http.NoBody)
+		assert.NoError(t, err)
+		if assert.NoError(t, Parse(r, &v)) {
+			assert.ElementsMatch(t, []string{}, v.Name)
+		}
+	})
+
+	t.Run("slice with empty", func(t *testing.T) {
+		var v struct {
+			Name []string `form:"name,optional"`
+		}
+
+		r, err := http.NewRequest(
+			http.MethodGet,
+			"/a?name=",
+			http.NoBody)
+		assert.NoError(t, err)
+		if assert.NoError(t, Parse(r, &v)) {
+			assert.ElementsMatch(t, []string{""}, v.Name)
+		}
+	})
+
 	t.Run("slice with empty and non-empty", func(t *testing.T) {
 		var v struct {
 			Name []string `form:"name"`
@@ -99,7 +129,67 @@ func TestParseFormArray(t *testing.T) {
 			http.NoBody)
 		assert.NoError(t, err)
 		if assert.NoError(t, Parse(r, &v)) {
-			assert.ElementsMatch(t, []string{"1"}, v.Name)
+			assert.ElementsMatch(t, []string{"", "1"}, v.Name)
+		}
+	})
+
+	t.Run("slice with one value on array format", func(t *testing.T) {
+		var v struct {
+			Names []string `form:"names"`
+		}
+
+		r, err := http.NewRequest(
+			http.MethodGet,
+			"/a?names=1,2,3",
+			http.NoBody)
+		assert.NoError(t, err)
+		if assert.NoError(t, Parse(r, &v)) {
+			assert.ElementsMatch(t, []string{"1", "2", "3"}, v.Names)
+		}
+	})
+
+	t.Run("slice with one value on combined array format", func(t *testing.T) {
+		var v struct {
+			Names []string `form:"names"`
+		}
+
+		r, err := http.NewRequest(
+			http.MethodGet,
+			"/a?names=[1,2,3]&names=4",
+			http.NoBody)
+		assert.NoError(t, err)
+		if assert.NoError(t, Parse(r, &v)) {
+			assert.ElementsMatch(t, []string{"[1,2,3]", "4"}, v.Names)
+		}
+	})
+
+	t.Run("slice with one value on integer array format", func(t *testing.T) {
+		var v struct {
+			Numbers []int `form:"numbers"`
+		}
+
+		r, err := http.NewRequest(
+			http.MethodGet,
+			"/a?numbers=1,2,3",
+			http.NoBody)
+		assert.NoError(t, err)
+		if assert.NoError(t, Parse(r, &v)) {
+			assert.ElementsMatch(t, []int{1, 2, 3}, v.Numbers)
+		}
+	})
+
+	t.Run("slice with one value on array format brackets", func(t *testing.T) {
+		var v struct {
+			Names []string `form:"names"`
+		}
+
+		r, err := http.NewRequest(
+			http.MethodGet,
+			"/a?names[]=1&names[]=2&names[]=3",
+			http.NoBody)
+		assert.NoError(t, err)
+		if assert.NoError(t, Parse(r, &v)) {
+			assert.ElementsMatch(t, []string{"1", "2", "3"}, v.Names)
 		}
 	})
 }
@@ -528,6 +618,26 @@ func TestCustomUnmarshalerStructRequest(t *testing.T) {
 	assert.Equal(t, "hello", v.Foo.Name)
 }
 
+func TestParseJsonStringRequest(t *testing.T) {
+	type GoodsInfo struct {
+		Sku int64 `json:"sku,optional"`
+	}
+
+	type GetReq struct {
+		GoodsList []*GoodsInfo `json:"goods_list"`
+	}
+
+	input := `{"goods_list":"[{\"sku\":11},{\"sku\":22}]"}`
+	r := httptest.NewRequest(http.MethodPost, "/a", strings.NewReader(input))
+	r.Header.Set(ContentType, JsonContentType)
+	var v GetReq
+	assert.NotPanics(t, func() {
+		assert.NoError(t, Parse(r, &v))
+		assert.Equal(t, 2, len(v.GoodsList))
+		assert.ElementsMatch(t, []int64{11, 22}, []int64{v.GoodsList[0].Sku, v.GoodsList[1].Sku})
+	})
+}
+
 func BenchmarkParseRaw(b *testing.B) {
 	r, err := http.NewRequest(http.MethodGet, "http://hello.com/a?name=hello&age=18&percent=3.4", http.NoBody)
 	if err != nil {

rest/httpx/util.go

@@ -2,12 +2,23 @@ package httpx
 
 import (
 	"errors"
+	"fmt"
 	"net/http"
+	"strings"
 )
 
-const xForwardedFor = "X-Forwarded-For"
+const (
+	xForwardedFor = "X-Forwarded-For"
+	arraySuffix   = "[]"
+	// most servers and clients have a limit of 8192 bytes (8 KB)
+	// one parameter at least take 4 chars, for example `?a=b&c=d`
+	maxFormParamCount = 2048
+)
 
-// GetFormValues returns the form values.
+// GetFormValues returns the form values supporting three array notation formats:
+//  1. Standard notation: /api?names=alice&names=bob
+//  2. Comma notation: /api?names=alice,bob
+//  3. Bracket notation: /api?names[]=alice&names[]=bob
 func GetFormValues(r *http.Request) (map[string]any, error) {
 	if err := r.ParseForm(); err != nil {
 		return nil, err
@@ -19,16 +30,23 @@ func GetFormValues(r *http.Request) (map[string]any, error) {
 		}
 	}
 
+	var n int
 	params := make(map[string]any, len(r.Form))
 	for name, values := range r.Form {
 		filtered := make([]string, 0, len(values))
 		for _, v := range values {
-			if len(v) > 0 {
+			if n < maxFormParamCount {
 				filtered = append(filtered, v)
+				n++
+			} else {
+				return nil, fmt.Errorf("too many form values, error: %s", r.Form.Encode())
 			}
 		}
 
 		if len(filtered) > 0 {
+			if strings.HasSuffix(name, arraySuffix) {
+				name = name[:len(name)-2]
+			}
 			params[name] = filtered
 		}
 	}

rest/httpx/util_test.go

@@ -1,7 +1,9 @@
 package httpx
 
 import (
+	"fmt"
 	"net/http"
+	"net/url"
 	"strings"
 	"testing"
 
@@ -23,3 +25,23 @@ func TestGetRemoteAddrNoHeader(t *testing.T) {
 
 	assert.True(t, len(GetRemoteAddr(r)) == 0)
 }
+
+func TestGetFormValues_TooManyValues(t *testing.T) {
+	form := url.Values{}
+
+	// Add more values than the limit
+	for i := 0; i < maxFormParamCount+10; i++ {
+		form.Add("param", fmt.Sprintf("value%d", i))
+	}
+
+	// Create a new request with the form data
+	req, err := http.NewRequest("POST", "/test", strings.NewReader(form.Encode()))
+	assert.NoError(t, err)
+
+	// Set the content type for form data
+	req.Header.Set(ContentType, "application/x-www-form-urlencoded")
+
+	_, err = GetFormValues(req)
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "too many form values")
+}

rest/router/patrouter_test.go

@@ -516,28 +516,55 @@ func TestParsePtrInRequestEmpty(t *testing.T) {
 }
 
 func TestParseQueryOptional(t *testing.T) {
-	r, err := http.NewRequest(http.MethodGet, "http://hello.com/kevin/2017?nickname=whatever&zipcode=", nil)
-	assert.Nil(t, err)
+	t.Run("optional with string", func(t *testing.T) {
+		r, err := http.NewRequest(http.MethodGet, "http://hello.com/kevin/2017?nickname=whatever&zipcode=", nil)
+		assert.Nil(t, err)
 
-	router := NewRouter()
-	err = router.Handle(http.MethodGet, "/:name/:year", http.HandlerFunc(
-		func(w http.ResponseWriter, r *http.Request) {
-			v := struct {
-				Nickname string `form:"nickname"`
-				Zipcode  int64  `form:"zipcode,optional"`
-			}{}
+		router := NewRouter()
+		err = router.Handle(http.MethodGet, "/:name/:year", http.HandlerFunc(
+			func(w http.ResponseWriter, r *http.Request) {
+				v := struct {
+					Nickname string `form:"nickname"`
+					Zipcode  string `form:"zipcode,optional"`
+				}{}
 
-			err = httpx.Parse(r, &v)
-			assert.Nil(t, err)
-			_, err = io.WriteString(w, fmt.Sprintf("%s:%d", v.Nickname, v.Zipcode))
-			assert.Nil(t, err)
-		}))
-	assert.Nil(t, err)
+				err = httpx.Parse(r, &v)
+				assert.Nil(t, err)
+				_, err = io.WriteString(w, fmt.Sprintf("%s:%s", v.Nickname, v.Zipcode))
+				assert.Nil(t, err)
+			}))
+		assert.Nil(t, err)
 
-	rr := httptest.NewRecorder()
-	router.ServeHTTP(rr, r)
+		rr := httptest.NewRecorder()
+		router.ServeHTTP(rr, r)
 
-	assert.Equal(t, "whatever:0", rr.Body.String())
+		assert.Equal(t, "whatever:", rr.Body.String())
+	})
+
+	t.Run("optional with int", func(t *testing.T) {
+		r, err := http.NewRequest(http.MethodGet, "http://hello.com/kevin/2017?nickname=whatever", nil)
+		assert.Nil(t, err)
+
+		router := NewRouter()
+		err = router.Handle(http.MethodGet, "/:name/:year", http.HandlerFunc(
+			func(w http.ResponseWriter, r *http.Request) {
+				v := struct {
+					Nickname string `form:"nickname"`
+					Zipcode  int    `form:"zipcode,optional"`
+				}{}
+
+				err = httpx.Parse(r, &v)
+				assert.Nil(t, err)
+				_, err = io.WriteString(w, fmt.Sprintf("%s:%d", v.Nickname, v.Zipcode))
+				assert.Nil(t, err)
+			}))
+		assert.Nil(t, err)
+
+		rr := httptest.NewRecorder()
+		router.ServeHTTP(rr, r)
+
+		assert.Equal(t, "whatever:0", rr.Body.String())
+	})
 }
 
 func TestParse(t *testing.T) {