chore(MeshHTTPRoute): default catch all path in route match

pkg/plugins/policies/meshhttproute/plugin/v1alpha1/listeners.go

@@ -127,12 +127,8 @@ func prepareRoutes(
 		}
 	}
 
-	catchAllMatch := []api.Match{{
-		Path: &api.PathMatch{
-			Value: "/",
-			Type:  api.PathPrefix,
-		},
-	}}
+	catchAllPathMatch := api.PathMatch{Value: "/", Type: api.PathPrefix}
+	catchAllMatch := []api.Match{{Path: pointer.To(catchAllPathMatch)}}
 
 	noCatchAll := slices.IndexFunc(rules, func(rule api.Rule) bool {
 		return reflect.DeepEqual(rule.Matches, catchAllMatch)
@@ -146,8 +142,23 @@ func prepareRoutes(
 
 	var routes []Route
 	for _, rule := range rules {
+		var matches []api.Match
+
+		for _, match := range rule.Matches {
+			if match.Path == nil {
+				// According to Envoy docs, match must have precisely one of
+				// prefix, path, safe_regex, connect_matcher,
+				// path_separated_prefix, path_match_policy set, so when policy
+				// doesn't specify explicit type of matching, we are assuming
+				// "catch all" path (any path starting with "/").
+				match.Path = pointer.To(catchAllPathMatch)
+			}
+
+			matches = append(matches, match)
+		}
+
 		route := Route{
-			Matches: rule.Matches,
+			Matches: matches,
 		}
 
 		if rule.Default.BackendRefs != nil {

pkg/plugins/policies/meshhttproute/plugin/v1alpha1/testdata/basic.listeners.golden.yaml

@@ -59,6 +59,7 @@ resources:
                   cluster: backend-_0_
                   timeout: 0s
               - match:
+                  prefix: /
                   queryParameters:
                   - name: v1
                     stringMatch:

pkg/plugins/policies/meshhttproute/plugin/v1alpha1/testdata/headers-match.listeners.golden.yaml

@@ -45,6 +45,7 @@ resources:
                   - name: foo-prefix
                     stringMatch:
                       prefix: x
+                  prefix: /
                 route:
                   cluster: backend
                   timeout: 0s