add custom binding (#2428)

* add custom binding

* fix test

* fix empty value

encoding/form/proto_decode.go

@@ -99,6 +99,9 @@ func getDescriptorByFieldAndName(fields protoreflect.FieldDescriptors, fieldName
 }
 
 func populateField(fd protoreflect.FieldDescriptor, v protoreflect.Message, value string) error {
+	if value == "" {
+		return nil
+	}
 	val, err := parseField(fd, value)
 	if err != nil {
 		return fmt.Errorf("parsing field %q: %w", fd.FullName().Name(), err)

transport/http/codec.go

@@ -4,10 +4,13 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
 
 	"github.com/go-kratos/kratos/v2/encoding"
 	"github.com/go-kratos/kratos/v2/errors"
 	"github.com/go-kratos/kratos/v2/internal/httputil"
+	"github.com/go-kratos/kratos/v2/transport/http/binding"
+	"github.com/gorilla/mux"
 )
 
 // SupportPackageIsVersion1 These constants should not be referenced from any other code.
@@ -37,6 +40,21 @@ type EncodeResponseFunc func(http.ResponseWriter, *http.Request, interface{}) er
 // EncodeErrorFunc is encode error func.
 type EncodeErrorFunc func(http.ResponseWriter, *http.Request, error)
 
+// DefaultRequestVars decodes the request vars to object.
+func DefaultRequestVars(r *http.Request, v interface{}) error {
+	raws := mux.Vars(r)
+	vars := make(url.Values, len(raws))
+	for k, v := range raws {
+		vars[k] = []string{v}
+	}
+	return binding.BindQuery(vars, v)
+}
+
+// DefaultRequestQuery decodes the request vars to object.
+func DefaultRequestQuery(r *http.Request, v interface{}) error {
+	return binding.BindQuery(r.URL.Query(), v)
+}
+
 // DefaultRequestDecoder decodes the request body to object.
 func DefaultRequestDecoder(r *http.Request, v interface{}) error {
 	codec, ok := CodecForRequest(r, "Content-Type")

transport/http/context.go

@@ -96,9 +96,9 @@ func (c *wrapper) Middleware(h middleware.Handler) middleware.Handler {
 	}
 	return middleware.Chain(c.router.srv.middleware.Match(c.req.URL.Path)...)(h)
 }
-func (c *wrapper) Bind(v interface{}) error      { return c.router.srv.dec(c.req, v) }
+func (c *wrapper) Bind(v interface{}) error      { return c.router.srv.decBody(c.req, v) }
-func (c *wrapper) BindVars(v interface{}) error  { return binding.BindQuery(c.Vars(), v) }
+func (c *wrapper) BindVars(v interface{}) error  { return c.router.srv.decVars(c.req, v) }
-func (c *wrapper) BindQuery(v interface{}) error { return binding.BindQuery(c.Query(), v) }
+func (c *wrapper) BindQuery(v interface{}) error { return c.router.srv.decQuery(c.req, v) }
 func (c *wrapper) BindForm(v interface{}) error  { return binding.BindForm(c.req, v) }
 func (c *wrapper) Returns(v interface{}, err error) error {
 	if err != nil {

transport/http/context_test.go

@@ -12,9 +12,11 @@ import (
 	"time"
 )
 
+var testRouter = &Router{srv: NewServer()}
+
 func TestContextHeader(t *testing.T) {
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    &http.Request{Header: map[string][]string{"name": {"kratos"}}},
 		res:    nil,
 		w:      responseWriter{},
@@ -27,7 +29,7 @@ func TestContextHeader(t *testing.T) {
 
 func TestContextForm(t *testing.T) {
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    &http.Request{Header: map[string][]string{"name": {"kratos"}}, Method: "POST"},
 		res:    nil,
 		w:      responseWriter{},
@@ -38,7 +40,7 @@ func TestContextForm(t *testing.T) {
 	}
 
 	w = wrapper{
-		router: nil,
+		router: testRouter,
 		req:    &http.Request{Form: map[string][]string{"name": {"kratos"}}},
 		res:    nil,
 		w:      responseWriter{},
@@ -51,7 +53,7 @@ func TestContextForm(t *testing.T) {
 
 func TestContextQuery(t *testing.T) {
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    &http.Request{URL: &url.URL{Scheme: "https", Host: "github.com", Path: "go-kratos/kratos", RawQuery: "page=1"}, Method: "POST"},
 		res:    nil,
 		w:      responseWriter{},
@@ -65,7 +67,7 @@ func TestContextQuery(t *testing.T) {
 func TestContextRequest(t *testing.T) {
 	req := &http.Request{Method: "POST"}
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    req,
 		res:    nil,
 		w:      responseWriter{},
@@ -100,7 +102,7 @@ func TestContextResponse(t *testing.T) {
 
 func TestContextBindQuery(t *testing.T) {
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    &http.Request{URL: &url.URL{Scheme: "https", Host: "go-kratos-dev", RawQuery: "page=2"}},
 		res:    nil,
 		w:      responseWriter{},
@@ -120,7 +122,7 @@ func TestContextBindQuery(t *testing.T) {
 
 func TestContextBindForm(t *testing.T) {
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    &http.Request{URL: &url.URL{Scheme: "https", Host: "go-kratos-dev"}, Form: map[string][]string{"page": {"2"}}},
 		res:    nil,
 		w:      responseWriter{},
@@ -141,7 +143,7 @@ func TestContextBindForm(t *testing.T) {
 func TestContextResponseReturn(t *testing.T) {
 	writer := httptest.NewRecorder()
 	w := wrapper{
-		router: nil,
+		router: testRouter,
 		req:    nil,
 		res:    writer,
 		w:      responseWriter{},
@@ -174,7 +176,7 @@ func TestContextCtx(t *testing.T) {
 	req := &http.Request{Method: "POST"}
 	req = req.WithContext(ctx)
 	w := wrapper{
-		router: &Router{srv: &Server{enc: DefaultResponseEncoder}},
+		router: testRouter,
 		req:    req,
 		res:    nil,
 		w:      responseWriter{},

transport/http/server.go

@@ -70,10 +70,24 @@ func Filter(filters ...FilterFunc) ServerOption {
 	}
 }
 
+// RequestVarsDecoder with request decoder.
+func RequestVarsDecoder(dec DecodeRequestFunc) ServerOption {
+	return func(o *Server) {
+		o.decVars = dec
+	}
+}
+
+// RequestQueryDecoder with request decoder.
+func RequestQueryDecoder(dec DecodeRequestFunc) ServerOption {
+	return func(o *Server) {
+		o.decQuery = dec
+	}
+}
+
 // RequestDecoder with request decoder.
 func RequestDecoder(dec DecodeRequestFunc) ServerOption {
 	return func(o *Server) {
-		o.dec = dec
+		o.decBody = dec
 	}
 }
 
@@ -126,7 +140,9 @@ type Server struct {
 	timeout     time.Duration
 	filters     []FilterFunc
 	middleware  matcher.Matcher
-	dec         DecodeRequestFunc
+	decVars     DecodeRequestFunc
+	decQuery    DecodeRequestFunc
+	decBody     DecodeRequestFunc
 	enc         EncodeResponseFunc
 	ene         EncodeErrorFunc
 	strictSlash bool
@@ -140,7 +156,9 @@ func NewServer(opts ...ServerOption) *Server {
 		address:     ":0",
 		timeout:     1 * time.Second,
 		middleware:  matcher.New(),
-		dec:         DefaultRequestDecoder,
+		decVars:     DefaultRequestVars,
+		decQuery:    DefaultRequestQuery,
+		decBody:     DefaultRequestDecoder,
 		enc:         DefaultResponseEncoder,
 		ene:         DefaultErrorEncoder,
 		strictSlash: true,

transport/http/server_test.go

@@ -316,8 +316,8 @@ func TestRequestDecoder(t *testing.T) {
 	o := &Server{}
 	v := func(*http.Request, interface{}) error { return nil }
 	RequestDecoder(v)(o)
-	if o.dec == nil {
+	if o.decBody == nil {
-		t.Errorf("expected nil got %v", o.dec)
+		t.Errorf("expected nil got %v", o.decBody)
 	}
 }