Expose route for context

docs/07.Reference/7.02.Filters.md

@@ -1392,7 +1392,7 @@ Commmon Use-Cases:
 
 1. Replace Prefix:
 
-Substitute a prefix with `/account` and return a `302 Found` status code.
+Substitute a prefix with `/account` and return a `302 Found` status code. The prefix was decided in `pathPrefix` in te matchting rule in HTTPServer.
 
 ```yaml
 name: demo-pipeline
@@ -1402,7 +1402,6 @@ flow:
 filters:
 - name: redirectorv2
   kind: RedirectorV2
-  pathPrefix: /user
   path:
     type: ReplacePrefixMatch
     replacePrefixMatch: /account
@@ -1441,7 +1440,6 @@ filters:
   kind: RedirectorV2
   scheme: https
   hostname: newdomain.com
-  pathPrefix: /user
   path:
     type: ReplacePrefixMatch
     replacePrefixMatch: /account

pkg/context/context.go

@@ -73,6 +73,7 @@ type Context struct {
 
 	activeNs string
 
+	route     protocols.Route
 	requests  map[string]*requestRef
 	responses map[string]*responseRef
 
@@ -92,6 +93,20 @@ func New(span *tracing.Span) *Context {
 	return ctx
 }
 
+// SetRoute sets the route.
+func (ctx *Context) SetRoute(route protocols.Route) {
+	ctx.route = route
+}
+
+// GetRoute returns the route with the existing flag.
+func (ctx *Context) GetRoute() (protocols.Route, bool) {
+	if ctx.route == nil {
+		return nil, false
+	}
+
+	return ctx.route, true
+}
+
 // Span returns the span of this Context.
 func (ctx *Context) Span() *tracing.Span {
 	return ctx.span

pkg/filters/redirectorv2/redirectorv2.go

@@ -25,6 +25,7 @@ import (
 
 	"github.com/megaease/easegress/v2/pkg/context"
 	"github.com/megaease/easegress/v2/pkg/filters"
+	httprouters "github.com/megaease/easegress/v2/pkg/object/httpserver/routers"
 	"github.com/megaease/easegress/v2/pkg/protocols/httpprot"
 
 	gwapis "sigs.k8s.io/gateway-api/apis/v1beta1"
@@ -76,7 +77,6 @@ type (
 	Spec struct {
 		filters.BaseSpec `json:",inline"`
 
-		PathPrefix                       *string `json:"pathPrefix,omitempty"`
 		gwapis.HTTPRequestRedirectFilter `json:",inline"`
 	}
 )
@@ -108,10 +108,6 @@ func (s *Spec) Validate() error {
 				return errors.New("invalid path of Redirector, replaceFullPath can't be empty")
 			}
 		case gwapis.PrefixMatchHTTPPathModifier:
-			if s.PathPrefix == nil || *s.PathPrefix == "" {
-				return errors.New("invalid path of Redirector, pathPrefix can't be empty")
-			}
-
 			if s.Path.ReplacePrefixMatch == nil {
 				return errors.New("invalid path of Redirector, replacePrefixMatch can't be empty")
 			}
@@ -178,8 +174,25 @@ func (r *Redirector) Handle(ctx *context.Context) string {
 		case gwapis.FullPathHTTPPathModifier:
 			redirectURL.Path = string(*r.spec.Path.ReplaceFullPath)
 		case gwapis.PrefixMatchHTTPPathModifier:
+			route, existed := ctx.GetRoute()
+			if !existed {
+				ctx.AddTag("route not found")
+				break
+			}
+
+			if route.Protocol() != "http" {
+				ctx.AddTag("route is not an http route")
+				break
+			}
+
+			prefix := route.(httprouters.Route).GetPathPrefix()
+			if prefix == "" {
+				ctx.AddTag("route has no path prefix")
+				break
+			}
+
 			redirectURL.Path = r.subPrefix(redirectURL.Path,
-				*r.spec.PathPrefix, string(*r.spec.Path.ReplacePrefixMatch))
+				prefix, string(*r.spec.Path.ReplacePrefixMatch))
 		}
 	}
 

pkg/filters/redirectorv2/redirectorv2_test.go

@@ -22,12 +22,20 @@ import (
 	"testing"
 
 	"github.com/megaease/easegress/v2/pkg/context"
+	"github.com/megaease/easegress/v2/pkg/object/httpserver/routers"
 	"github.com/megaease/easegress/v2/pkg/protocols/httpprot"
 	"github.com/stretchr/testify/assert"
 
 	gwapis "sigs.k8s.io/gateway-api/apis/v1beta1"
 )
 
+type fakeMuxPath struct {
+	routers.Path
+}
+
+func (mp *fakeMuxPath) Protocol() string                      { return "http" }
+func (mp *fakeMuxPath) Rewrite(context *routers.RouteContext) {}
+
 func TestSpecValidate(t *testing.T) {
 	tests := []struct {
 		name      string
@@ -123,7 +131,7 @@ func TestSpecValidate(t *testing.T) {
 				},
 			},
 			expectErr: true,
-			errMsg:    "invalid path of Redirector, pathPrefix can't be empty",
+			errMsg:    "invalid path of Redirector, replacePrefixMatch can't be empty",
 		},
 	}
 
@@ -169,7 +177,6 @@ func TestRedirectorHandle2(t *testing.T) {
 			name:   "Redirect prefix",
 			reqURL: "http://localhost/user/data/profile",
 			spec: &Spec{
-				PathPrefix: new(string),
 				HTTPRequestRedirectFilter: gwapis.HTTPRequestRedirectFilter{
 					Path: &gwapis.HTTPPathModifier{
 						Type:               gwapis.PrefixMatchHTTPPathModifier,
@@ -232,13 +239,15 @@ func TestRedirectorHandle2(t *testing.T) {
 			req, _ := httpprot.NewRequest(stdReq)
 			ctx := context.New(nil)
 			ctx.SetInputRequest(req)
+			ctx.SetRoute(&fakeMuxPath{
+				Path: routers.Path{PathPrefix: "/user/"},
+			})
 
 			if tt.spec.Path != nil && tt.spec.Path.ReplaceFullPath != nil {
 				*tt.spec.Path.ReplaceFullPath = "/newpath"
 			}
 
 			if tt.spec.Path != nil && tt.spec.Path.ReplacePrefixMatch != nil {
-				*tt.spec.PathPrefix = "/user/"
 				*tt.spec.Path.ReplacePrefixMatch = "/account/"
 			}
 

pkg/object/httpserver/mux.go

@@ -129,7 +129,8 @@ func (mi *muxInstance) putRouteToCache(req *httpprot.Request, rc *cachedRoute) {
 }
 
 func newMux(httpStat *httpstat.HTTPStat, topN *httpstat.TopN,
-	metrics *metrics, mapper context.MuxMapper) *mux {
+	metrics *metrics, mapper context.MuxMapper,
+) *mux {
 	m := &mux{
 		httpStat: httpStat,
 		topN:     topN,
@@ -267,6 +268,8 @@ func (mi *muxInstance) serveHTTP(stdw http.ResponseWriter, stdr *http.Request) {
 
 	routeCtx := routers.NewContext(req)
 	route := mi.search(routeCtx)
+	ctx.SetRoute(route.route)
+
 	var respHeader http.Header
 
 	defer func() {

pkg/object/httpserver/routers/ordered/router.go

@@ -86,6 +86,10 @@ func newMuxPath(p *routers.Path) *muxPath {
 	}
 }
 
+func (mp *muxPath) Protocol() string {
+	return "http"
+}
+
 func (mp *muxPath) matchPath(path string) bool {
 	if mp.Path.Path == "" && mp.PathPrefix == "" && mp.pathRE == nil {
 		return true

pkg/object/httpserver/routers/radixtree/router.go

@@ -485,6 +485,10 @@ func (mp *muxPath) initRewrite() {
 	mp.rewriteTemplate = template.Must(template.New("").Parse(repl))
 }
 
+func (mp *muxPath) Protocol() string {
+	return "http"
+}
+
 func (mp *muxPath) Rewrite(context *routers.RouteContext) {
 	req := context.Request
 

pkg/object/httpserver/routers/routers.go

@@ -25,6 +25,7 @@ import (
 	"net/http"
 	"net/url"
 
+	"github.com/megaease/easegress/v2/pkg/protocols"
 	"github.com/megaease/easegress/v2/pkg/protocols/httpprot"
 )
 
@@ -49,12 +50,24 @@ type (
 
 	// Route is the corresponding route interface for different routing policies.
 	Route interface {
+		protocols.Route
+
 		// Rewrite for path rewriting.
 		Rewrite(context *RouteContext)
 		// GetBackend is used to get the backend corresponding to the route.
 		GetBackend() string
 		// GetClientMaxBodySize is used to get the clientMaxBodySize corresponding to the route.
 		GetClientMaxBodySize() int64
+
+		// NOTE: Currently we only support path information in readonly.
+		// Without further requirements, we choose not to expose too much information.
+
+		// GetExactPath is used to get the exact path corresponding to the route.
+		GetExactPath() string
+		// GetPathPrefix is used to get the path prefix corresponding to the route.
+		GetPathPrefix() string
+		// GetPathRegexp is used to get the path regexp corresponding to the route.
+		GetPathRegexp() string
 	}
 
 	// Params are used to store the variables in the search path and their corresponding values.

pkg/object/httpserver/routers/spec.go

@@ -252,6 +252,21 @@ func (p *Path) GetClientMaxBodySize() int64 {
 	return p.ClientMaxBodySize
 }
 
+// GetExactPath returns the exact path of the route.
+func (p *Path) GetExactPath() string {
+	return p.Path
+}
+
+// GetPathPrefix returns the path prefix of the route.
+func (p *Path) GetPathPrefix() string {
+	return p.PathPrefix
+}
+
+// GetPathRegexp returns the path regexp of the route.
+func (p *Path) GetPathRegexp() string {
+	return p.PathRegexp
+}
+
 func (hs Headers) init() {
 	for _, h := range hs {
 		if h.Regexp != "" {

pkg/protocols/protocols.go

@@ -150,3 +150,10 @@ type Protocol interface {
 	NewResponseInfo() interface{}
 	BuildResponse(respInfo interface{}) (Response, error)
 }
+
+// Route is the interface of a route.
+// Filters could assert the real type according to the protocol.
+type Route interface {
+	// Protocol returns the canonical name of the protocol in lower case, such as http, grpc.
+	Protocol() string
+}