fix PathSeparatedPrefix & optimize the prefix ends with / logic.

internal/xds/translator/route.go

@@ -7,6 +7,7 @@ package translator
 
 import (
 	"fmt"
+	"strings"
 
 	corev3 "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
 	listenerv3 "github.com/envoyproxy/go-control-plane/envoy/config/listener/v3"
@@ -96,9 +97,10 @@ func buildXdsRouteMatch(pathMatch *ir.StringMatch, headerMatches []*ir.StringMat
 				Path: *pathMatch.Exact,
 			}
 		} else if pathMatch.Prefix != nil {
-			if *pathMatch.Prefix == "/" {
+			// when the prefix ends with "/", use RouteMatch_Prefix
+			if strings.HasSuffix(*pathMatch.Prefix, "/") {
 				outMatch.PathSpecifier = &routev3.RouteMatch_Prefix{
-					Prefix: "/",
+					Prefix: *pathMatch.Prefix,
 				}
 			} else {
 				outMatch.PathSpecifier = &routev3.RouteMatch_PathSeparatedPrefix{

internal/xds/translator/testdata/in/xds-ir/http-route-rewrite-root-path-url-prefix.yaml

@@ -0,0 +1,20 @@
+name: "http-route"
+http:
+- name: "first-listener"
+  address: "0.0.0.0"
+  port: 10080
+  hostnames:
+  - "*"
+  routes:
+  - name: "rewrite-route"
+    pathMatch:
+      prefix: "/origin/"
+    headerMatches:
+    - name: ":authority"
+      exact: gateway.envoyproxy.io
+    destinations:
+    - host: "1.2.3.4"
+      port: 50000
+    urlRewrite:
+      path:
+        prefixMatchReplace: /

internal/xds/translator/testdata/out/xds-ir/http-route-rewrite-root-path-url-prefix.clusters.yaml

@@ -0,0 +1,18 @@
+- commonLbConfig:
+    localityWeightedLbConfig: {}
+  connectTimeout: 10s
+  dnsLookupFamily: V4_ONLY
+  loadAssignment:
+    clusterName: rewrite-route
+    endpoints:
+    - lbEndpoints:
+      - endpoint:
+          address:
+            socketAddress:
+              address: 1.2.3.4
+              portValue: 50000
+      loadBalancingWeight: 1
+      locality: {}
+  name: rewrite-route
+  outlierDetection: {}
+  type: STATIC

internal/xds/translator/testdata/out/xds-ir/http-route-rewrite-root-path-url-prefix.listeners.yaml

@@ -0,0 +1,37 @@
+- accessLog:
+  - filter:
+      responseFlagFilter:
+        flags:
+        - NR
+    name: envoy.access_loggers.file
+    typedConfig:
+      '@type': type.googleapis.com/envoy.extensions.access_loggers.file.v3.FileAccessLog
+      path: /dev/stdout
+  address:
+    socketAddress:
+      address: 0.0.0.0
+      portValue: 10080
+  defaultFilterChain:
+    filters:
+    - name: envoy.filters.network.http_connection_manager
+      typedConfig:
+        '@type': type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
+        accessLog:
+        - name: envoy.access_loggers.file
+          typedConfig:
+            '@type': type.googleapis.com/envoy.extensions.access_loggers.file.v3.FileAccessLog
+            path: /dev/stdout
+        httpFilters:
+        - name: envoy.filters.http.router
+          typedConfig:
+            '@type': type.googleapis.com/envoy.extensions.filters.http.router.v3.Router
+        rds:
+          configSource:
+            ads: {}
+            resourceApiVersion: V3
+          routeConfigName: first-listener
+        statPrefix: http
+        upgradeConfigs:
+        - upgradeType: websocket
+        useRemoteAddress: true
+  name: first-listener

internal/xds/translator/testdata/out/xds-ir/http-route-rewrite-root-path-url-prefix.routes.yaml

@@ -0,0 +1,15 @@
+- name: first-listener
+  virtualHosts:
+  - domains:
+    - '*'
+    name: first-listener
+    routes:
+    - match:
+        headers:
+        - name: :authority
+          stringMatch:
+            exact: gateway.envoyproxy.io
+        prefix: /origin/
+      route:
+        cluster: rewrite-route
+        prefixRewrite: /

internal/xds/translator/translator_test.go

@@ -98,6 +98,9 @@ func TestTranslateXds(t *testing.T) {
 		{
 			name: "http-route-rewrite-url-prefix",
 		},
+		{
+			name: "http-route-rewrite-root-path-url-prefix",
+		},
 		{
 			name: "http-route-rewrite-url-fullpath",
 		},