[feat gw-api]update behavior and doc

Author: shuqz

docs/guide/gateway/l7gateway.md

@@ -206,9 +206,9 @@ The AWS Load Balancer Controller supports HTTPRoute RequestRedirect filters with
 
 **ReplacePrefixMatch Behavior:**
 
-The behavior of `ReplacePrefixMatch` depends on whether other redirect components are modified:
+We support `ReplacePrefixMatch` with limitations:
 
-1. **With scheme/port/hostname changes** - Path suffixes are preserved:
+1. **With scheme/port/hostname changes** - Works as expected:
    ```yaml
    filters:
    - type: RequestRedirect
@@ -221,7 +221,7 @@ The behavior of `ReplacePrefixMatch` depends on whether other redirect component
    - Request: `/old-prefix/path/to/resource`
    - Redirects to: `/new-prefix/path/to/resource` ✅ (suffix preserved)
 
-2. **Without other component changes** - Only prefix is replaced, suffixes are NOT preserved:
+2. **Without other component changes** - AWS ALB will reject with redirect loop error:
    ```yaml
    filters:
    - type: RequestRedirect
@@ -230,13 +230,14 @@ The behavior of `ReplacePrefixMatch` depends on whether other redirect component
          type: ReplacePrefixMatch
          replacePrefixMatch: /new-prefix
    ```
-   - Request: `/old-prefix/path/to/resource`
-   - Redirects to: `/new-prefix` ❌ (suffix lost)
+   - This configuration will be rejected by the API with "InvalidLoadBalancerAction: The redirect configuration is not valid because it creates a loop." ❌
 
 **Recommendations:**
 
-- For path-only redirects with exact paths, use `ReplaceFullPath`
-- To preserve path suffixes with prefix replacement, also modify `scheme`, `port`, or `hostname`
+- For path-only redirects, use `ReplaceFullPath` instead
+- To use `ReplacePrefixMatch`, you must also modify `scheme`, `port`, or `hostname`
+
+**Important**: If one HTTPRoute rule has an invalid redirect configuration (e.g., path-only redirect with `ReplacePrefixMatch` that cause redirect loop), the controller will fail to create that listener rule and stop processing subsequent rules in the same HTTPRoute. This means valid rules with lower precedence (shorter paths, later in the route) will not be created. 
 
 #### Examples
 

pkg/gateway/routeutils/route_rule_action.go

@@ -225,7 +225,6 @@ func buildHttpRuleRedirectActionsBasedOnFilter(filters []gwv1.HTTPRouteFilter, r
 // buildHttpRedirectAction configure filter attributes to RedirectActionConfig
 // gateway api has no attribute to specify query, use listener rule configuration
 func buildHttpRedirectAction(filter *gwv1.HTTPRequestRedirectFilter, redirectConfig *elbv2gw.RedirectActionConfig) (*elbv2model.Action, error) {
-	isComponentSpecified := false
 	var statusCode string
 	if filter.StatusCode != nil {
 		statusCodeStr := fmt.Sprintf("HTTP_%d", *filter.StatusCode)
@@ -236,7 +235,6 @@ func buildHttpRedirectAction(filter *gwv1.HTTPRequestRedirectFilter, redirectCon
 	if filter.Port != nil {
 		portStr := fmt.Sprintf("%d", *filter.Port)
 		port = &portStr
-		isComponentSpecified = true
 	}
 
 	var protocol *string
@@ -246,7 +244,6 @@ func buildHttpRedirectAction(filter *gwv1.HTTPRequestRedirectFilter, redirectCon
 			return nil, errors.Errorf("unsupported redirect scheme: %v", upperScheme)
 		}
 		protocol = &upperScheme
-		isComponentSpecified = true
 	}
 
 	var path *string
@@ -257,28 +254,18 @@ func buildHttpRedirectAction(filter *gwv1.HTTPRequestRedirectFilter, redirectCon
 				return nil, errors.Errorf("ReplaceFullPath shouldn't contain wildcards: %v", pathValue)
 			}
 			path = filter.Path.ReplaceFullPath
-			isComponentSpecified = true
 		} else if filter.Path.ReplacePrefixMatch != nil {
-			// Use #{path} if other components are modified (avoids redirect loop)
-			// Otherwise use literal prefix (no suffix preservation)
-			if filter.Scheme != nil || filter.Port != nil || filter.Hostname != nil {
-				pathVariable := "/#{path}"
-				path = &pathVariable
-			} else {
-				path = filter.Path.ReplacePrefixMatch
+			//url rewrite will handle path transform
+			pathValue := *filter.Path.ReplacePrefixMatch
+			if strings.ContainsAny(pathValue, "*?") {
+				return nil, errors.Errorf("ReplacePrefixMatch shouldn't contain wildcards: %v", pathValue)
 			}
-			isComponentSpecified = true
 		}
 	}
 
 	var hostname *string
 	if filter.Hostname != nil {
 		hostname = (*string)(filter.Hostname)
-		isComponentSpecified = true
-	}
-
-	if !isComponentSpecified {
-		return nil, errors.Errorf("To avoid a redirect loop, you must modify at least one of the following components: protocol, port, hostname or path.")
 	}
 
 	var query *string

pkg/gateway/routeutils/route_rule_action_test.go

@@ -66,59 +66,7 @@ func Test_buildHttpRedirectAction(t *testing.T) {
 			wantErr: false,
 		},
 		{
-			name: "redirect with prefix match only - uses literal prefix",
-			filter: &gwv1.HTTPRequestRedirectFilter{
-				Path: &gwv1.HTTPPathModifier{
-					Type:               gwv1.PrefixMatchHTTPPathModifier,
-					ReplacePrefixMatch: &replacePrefixPath,
-				},
-			},
-			want: &elbv2model.Action{
-				Type: elbv2model.ActionTypeRedirect,
-				RedirectConfig: &elbv2model.RedirectActionConfig{
-					Path: &replacePrefixPath,
-				},
-			},
-			wantErr: false,
-		},
-		{
-			name: "redirect with prefix match and scheme - uses #{path}",
-			filter: &gwv1.HTTPRequestRedirectFilter{
-				Scheme: &scheme,
-				Path: &gwv1.HTTPPathModifier{
-					Type:               gwv1.PrefixMatchHTTPPathModifier,
-					ReplacePrefixMatch: &replacePrefixPath,
-				},
-			},
-			want: &elbv2model.Action{
-				Type: elbv2model.ActionTypeRedirect,
-				RedirectConfig: &elbv2model.RedirectActionConfig{
-					Path:     awssdk.String("/#{path}"),
-					Protocol: &expectedScheme,
-				},
-			},
-			wantErr: false,
-		},
-		{
-			name: "redirect with prefix match and port - uses #{path}",
-			filter: &gwv1.HTTPRequestRedirectFilter{
-				Port: (*gwv1.PortNumber)(&port),
-				Path: &gwv1.HTTPPathModifier{
-					Type:               gwv1.PrefixMatchHTTPPathModifier,
-					ReplacePrefixMatch: &replacePrefixPath,
-				},
-			},
-			want: &elbv2model.Action{
-				Type: elbv2model.ActionTypeRedirect,
-				RedirectConfig: &elbv2model.RedirectActionConfig{
-					Path: awssdk.String("/#{path}"),
-					Port: &portString,
-				},
-			},
-			wantErr: false,
-		},
-		{
-			name: "redirect with prefix match and hostname - uses #{path}",
+			name: "redirect with prefix  - no path in redirect config",
 			filter: &gwv1.HTTPRequestRedirectFilter{
 				Hostname: (*gwv1.PreciseHostname)(&hostname),
 				Path: &gwv1.HTTPPathModifier{
@@ -129,18 +77,11 @@ func Test_buildHttpRedirectAction(t *testing.T) {
 			want: &elbv2model.Action{
 				Type: elbv2model.ActionTypeRedirect,
 				RedirectConfig: &elbv2model.RedirectActionConfig{
-					Path: awssdk.String("/#{path}"),
 					Host: &hostname,
 				},
 			},
 			wantErr: false,
 		},
-		{
-			name:    "redirect with no component provided",
-			filter:  &gwv1.HTTPRequestRedirectFilter{},
-			want:    nil,
-			wantErr: true,
-		},
 		{
 			name: "invalid scheme provided",
 			filter: &gwv1.HTTPRequestRedirectFilter{