feat: add rewrite:RespHeaders and modify the upstream response ers via request implementation

docs/en/latest/getting-started.md

@@ -129,8 +129,8 @@ func (p *Say) Filter(conf interface{}, w http.ResponseWriter, r pkgHTTP.Request)
 ```
 
 We can see that the Filter takes the value of the body set in the configuration as the response body. If we call `Write` or `WriteHeader` of the `http.ResponseWriter`
-(respond directly in the plugin), it will response directly in the APISIX without touching the upstream. As we only support setting headers of local response,
-calling `Header` won't take any effects without calling `Write` or `WriteHeader`. (TODO: support setting response header separately)
+(respond directly in the plugin), it will response directly in the APISIX without touching the upstream. We can also set response headers in the plugin and touch the upstream
+at the same time by set RespHeader in `pkgHTTP.Request`.
 
 For the `pkgHTTP.Request`, you can refer to the API documentation provided by the Go Runner SDK:
 https://pkg.go.dev/github.com/apache/apisix-go-plugin-runner

go.mod

@@ -4,7 +4,7 @@ go 1.15
 
 require (
 	github.com/ReneKroon/ttlcache/v2 v2.4.0
-	github.com/api7/ext-plugin-proto v0.3.0
+	github.com/api7/ext-plugin-proto v0.4.0
 	github.com/google/flatbuffers v2.0.0+incompatible
 	github.com/spf13/cobra v1.1.3
 	github.com/stretchr/testify v1.7.0

internal/http/request.go

@@ -57,6 +57,8 @@ type Request struct {
 
 	ctx    context.Context
 	cancel context.CancelFunc
+
+	respHdr http.Header
 }
 
 func (r *Request) ConfToken() uint32 {
@@ -103,6 +105,13 @@ func (r *Request) Header() pkgHTTP.Header {
 	return r.hdr
 }
 
+func (r *Request) RespHeader() http.Header {
+	if r.respHdr == nil {
+		r.respHdr = http.Header{}
+	}
+	return r.respHdr
+}
+
 func cloneUrlValues(oldV url.Values) url.Values {
 	nv := 0
 	for _, vv := range oldV {
@@ -177,7 +186,7 @@ func (r *Request) Reset() {
 }
 
 func (r *Request) FetchChanges(id uint32, builder *flatbuffers.Builder) bool {
-	if r.path == nil && r.hdr == nil && r.args == nil {
+	if r.path == nil && r.hdr == nil && r.args == nil && r.respHdr == nil{
 		return false
 	}
 
@@ -186,7 +195,7 @@ func (r *Request) FetchChanges(id uint32, builder *flatbuffers.Builder) bool {
 		path = builder.CreateByteString(r.path)
 	}
 
-	var hdrVec flatbuffers.UOffsetT
+	var hdrVec,respHdrVec flatbuffers.UOffsetT
 	if r.hdr != nil {
 		hdrs := []flatbuffers.UOffsetT{}
 		oldHdr := r.rawHdr
@@ -222,6 +231,28 @@ func (r *Request) FetchChanges(id uint32, builder *flatbuffers.Builder) bool {
 		hdrVec = builder.EndVector(size)
 	}
 
+	if r.respHdr != nil {
+		respHdrs := []flatbuffers.UOffsetT{}
+		for n, arr := range r.respHdr {
+			for _, v := range arr {
+				name := builder.CreateString(n)
+				value := builder.CreateString(v)
+				A6.TextEntryStart(builder)
+				A6.TextEntryAddName(builder, name)
+				A6.TextEntryAddValue(builder, value)
+				te := A6.TextEntryEnd(builder)
+				respHdrs = append(respHdrs, te)
+			}
+		}
+		size := len(respHdrs)
+		hrc.RewriteStartRespHeadersVector(builder, size)
+		for i := size - 1; i >= 0; i-- {
+			te := respHdrs[i]
+			builder.PrependUOffsetT(te)
+		}
+		respHdrVec = builder.EndVector(size)
+	}
+
 	var argsVec flatbuffers.UOffsetT
 	if r.args != nil {
 		args := []flatbuffers.UOffsetT{}
@@ -267,6 +298,9 @@ func (r *Request) FetchChanges(id uint32, builder *flatbuffers.Builder) bool {
 	if hdrVec > 0 {
 		hrc.RewriteAddHeaders(builder, hdrVec)
 	}
+	if respHdrVec > 0{
+		hrc.RewriteAddRespHeaders(builder,respHdrVec)
+	}
 	if argsVec > 0 {
 		hrc.RewriteAddArgs(builder, argsVec)
 	}

internal/http/request_test.go

@@ -70,6 +70,7 @@ type reqOpt struct {
 	method  A6.Method
 	path    string
 	headers []pair
+	respHeader []pair
 	args    []pair
 }
 
@@ -87,7 +88,7 @@ func buildReq(opt reqOpt) []byte {
 	}
 
 	hdrLen := len(opt.headers)
-	var hdrVec flatbuffers.UOffsetT
+	var hdrVec,respHdrVec flatbuffers.UOffsetT
 	if hdrLen > 0 {
 		hdrs := []flatbuffers.UOffsetT{}
 		for _, v := range opt.headers {
@@ -108,6 +109,26 @@ func buildReq(opt reqOpt) []byte {
 		hdrVec = builder.EndVector(size)
 	}
 
+	if len(opt.respHeader) > 0 {
+		respHdrs := []flatbuffers.UOffsetT{}
+		for _, v := range opt.headers {
+			name := builder.CreateString(v.name)
+			value := builder.CreateString(v.value)
+			A6.TextEntryStart(builder)
+			A6.TextEntryAddName(builder, name)
+			A6.TextEntryAddValue(builder, value)
+			te := A6.TextEntryEnd(builder)
+			respHdrs = append(respHdrs, te)
+		}
+		size := len(respHdrs)
+		hrc.RewriteStartRespHeadersVector(builder, size)
+		for i := size - 1; i >= 0; i-- {
+			te := respHdrs[i]
+			builder.PrependUOffsetT(te)
+		}
+		respHdrVec = builder.EndVector(size)
+	}
+
 	argsLen := len(opt.args)
 	var argsVec flatbuffers.UOffsetT
 	if argsLen > 0 {
@@ -145,6 +166,9 @@ func buildReq(opt reqOpt) []byte {
 	if hdrVec > 0 {
 		hrc.ReqAddHeaders(builder, hdrVec)
 	}
+	if respHdrVec > 0{
+		hrc.RewriteAddRespHeaders(builder,respHdrVec)
+	}
 	if argsVec > 0 {
 		hrc.ReqAddArgs(builder, argsVec)
 	}
@@ -235,6 +259,8 @@ func TestHeader(t *testing.T) {
 	assert.Equal(t, exp, res)
 }
 
+
+
 func TestArgs(t *testing.T) {
 	out := buildReq(reqOpt{args: []pair{
 		{"del", "a"},
@@ -398,3 +424,30 @@ func TestContext(t *testing.T) {
 	ReuseRequest(r)
 	assert.Equal(t, r.ctx, nil)
 }
+
+func TestRespHeader(t *testing.T){
+	out := buildReq(reqOpt{})
+	r := CreateRequest(out)
+	respHdr := r.RespHeader()
+
+	respHdr.Set("resp-header","this is resp-header")
+	respHdr.Set("Set-Cookie","mycookie=test")
+
+	respHdr.Del("resp-header")
+
+	builder := util.GetBuilder()
+	assert.True(t, r.FetchChanges(1, builder))
+	rewrite := getRewriteAction(t, builder)
+	assert.Equal(t, 1, rewrite.RespHeadersLength())
+
+	exp := http.Header{}
+	exp.Set("Set-Cookie", "mycookie=test")
+	res := http.Header{}
+	for i := 0; i < rewrite.RespHeadersLength(); i++ {
+		e := &A6.TextEntry{}
+		rewrite.RespHeaders(e, i)
+		res.Add(string(e.Name()), string(e.Value()))
+	}
+	assert.Equal(t, exp, res)
+
+}

internal/plugin/plugin_test.go

@@ -375,3 +375,35 @@ func TestFilter_SetRespHeaderDoNotBreakReq(t *testing.T) {
 	assert.Equal(t, "bar", req.Header().Get("foo"))
 	assert.Equal(t, "baz", resp.Header().Get("foo"))
 }
+
+func TestFilter_SetRespHeader(t *testing.T) {
+	InitConfCache(1 * time.Millisecond)
+
+	filterSetRespHeaderParseConf := func(in []byte) (conf interface{}, err error) {
+		return "", nil
+	}
+	filterSetRespHeaderFilter := func(conf interface{}, w http.ResponseWriter, r pkgHTTP.Request) {
+		r.RespHeader().Set("foo", "baz")
+	}
+
+	RegisterPlugin("filterSetRespHeader", filterSetRespHeaderParseConf, filterSetRespHeaderFilter)
+
+	builder := flatbuffers.NewBuilder(1024)
+	filterSetRespName := builder.CreateString("filterSetRespHeader")
+	filterSetRespConf := builder.CreateString("a")
+	prepareConfWithData(builder, filterSetRespName, filterSetRespConf)
+
+	res, _ := GetRuleConf(1)
+	hrc.ReqStart(builder)
+	hrc.ReqAddId(builder, 233)
+	hrc.ReqAddConfToken(builder, 1)
+	r := hrc.ReqEnd(builder)
+	builder.Finish(r)
+	out := builder.FinishedBytes()
+
+	req := inHTTP.CreateRequest(out)
+	resp := inHTTP.CreateResponse()
+	filter(res, resp, req)
+
+	assert.Equal(t, "baz", req.RespHeader().Get("foo"))
+}

pkg/http/http.go

@@ -67,6 +67,9 @@ type Request interface {
 	//
 	// For run plugin, the context controls cancellation.
 	Context() context.Context
+	// RespHeader returns the response header
+	// Add or set response headers that exclude important headers likes `connection`,`content-length`,`transfer-encoding`,`location,server`,`www-authenticate`,`content-encoding`,`content-type`,`content-location` and `content-language`.
+	RespHeader() http.Header
 }
 
 // Header is like http.Header, but only implements the subset of its methods