support sort httproute when use gateway api (#622)

istio/1.12/patches/istio/20231103-gatewayapi-sort.patch

@@ -0,0 +1,377 @@
+diff -Naur istio/pilot/pkg/config/kube/gateway/conversion.go istio-new/pilot/pkg/config/kube/gateway/conversion.go
+--- istio/pilot/pkg/config/kube/gateway/conversion.go	2023-11-03 17:18:56.000000000 +0800
++++ istio-new/pilot/pkg/config/kube/gateway/conversion.go	2023-11-03 17:14:50.000000000 +0800
+@@ -151,15 +151,113 @@
+ 		}
+ 	}
+
++	// for gateway routes, build one VS per gateway+host
++	gatewayRoutes := make(map[string]map[string]*config.Config)
++
+ 	for _, obj := range r.HTTPRoute {
+-		if vsConfig := buildHTTPVirtualServices(obj, gatewayMap, r.Domain); vsConfig != nil {
++		buildHTTPVirtualServices(r, obj, gatewayMap, gatewayRoutes, r.Domain)
++	}
++	for _, vsByHost := range gatewayRoutes {
++		for _, vsConfig := range vsByHost {
+ 			result = append(result, *vsConfig)
+ 		}
+ 	}
+ 	return result
+ }
+
+-func buildHTTPVirtualServices(obj config.Config, gateways map[parentKey]map[gatewayapiV1beta1.SectionName]*parentInfo, domain string) *config.Config {
++// getURIRank ranks a URI match type. Exact > Prefix > Regex
++func getURIRank(match *istio.HTTPMatchRequest) int {
++	if match.Uri == nil {
++		return -1
++	}
++	switch match.Uri.MatchType.(type) {
++	case *istio.StringMatch_Exact:
++		return 3
++	case *istio.StringMatch_Prefix:
++		return 2
++	case *istio.StringMatch_Regex:
++		// TODO optimize in new verison envoy
++		if strings.HasSuffix(match.Uri.GetRegex(), prefixMatchRegex) &&
++			!strings.ContainsAny(strings.TrimSuffix(match.Uri.GetRegex(), prefixMatchRegex), `\.+*?()|[]{}^$`) {
++			return 2
++		}
++		return 1
++	}
++	// should not happen
++	return -1
++}
++
++func getURILength(match *istio.HTTPMatchRequest) int {
++	if match.Uri == nil {
++		return 0
++	}
++	switch match.Uri.MatchType.(type) {
++	case *istio.StringMatch_Prefix:
++		return len(match.Uri.GetPrefix())
++	case *istio.StringMatch_Exact:
++		return len(match.Uri.GetExact())
++	case *istio.StringMatch_Regex:
++		return len(match.Uri.GetRegex())
++	}
++	// should not happen
++	return -1
++}
++
++// sortHTTPRoutes sorts generated vs routes to meet gateway-api requirements
++// see https://gateway-api.sigs.k8s.io/v1alpha2/references/spec/#gateway.networking.k8s.io/v1alpha2.HTTPRouteRule
++func sortHTTPRoutes(routes []*istio.HTTPRoute) {
++	sort.SliceStable(routes, func(i, j int) bool {
++		if len(routes[i].Match) == 0 {
++			return false
++		} else if len(routes[j].Match) == 0 {
++			return true
++		}
++		// Only look at match[0], we always generate only one match
++		m1, m2 := routes[i].Match[0], routes[j].Match[0]
++		r1, r2 := getURIRank(m1), getURIRank(m2)
++		len1, len2 := getURILength(m1), getURILength(m2)
++		switch {
++		// 1: Exact/Prefix/Regex
++		case r1 != r2:
++			return r1 > r2
++		case len1 != len2:
++			return len1 > len2
++			// 2: method math
++		case (m1.Method == nil) != (m2.Method == nil):
++			return m1.Method != nil
++			// 3: number of header matches
++		case len(m1.Headers) != len(m2.Headers):
++			return len(m1.Headers) > len(m2.Headers)
++			// 4: number of query matches
++		default:
++			return len(m1.QueryParams) > len(m2.QueryParams)
++		}
++	})
++}
++
++func routeMeta(obj config.Config) map[string]string {
++	m := parentMeta(obj, nil)
++	m[constants.InternalRouteSemantics] = constants.RouteSemanticsGateway
++	return m
++}
++
++func filteredReferences(parents []routeParentReference) []routeParentReference {
++	ret := make([]routeParentReference, 0, len(parents))
++	for _, p := range parents {
++		if p.DeniedReason != nil {
++			// We should filter this out
++			continue
++		}
++		ret = append(ret, p)
++	}
++	// To ensure deterministic order, sort them
++	sort.Slice(ret, func(i, j int) bool {
++		return ret[i].InternalName < ret[j].InternalName
++	})
++	return ret
++}
++
++func buildHTTPVirtualServices(ctx *KubernetesResources, obj config.Config, gateways map[parentKey]map[gatewayapiV1beta1.SectionName]*parentInfo, gatewayRoutes map[string]map[string]*config.Config, domain string) {
+ 	route := obj.Spec.(*gatewayapiV1beta1.HTTPRouteSpec)
+
+ 	parentRefs := extractParentReferenceInfo(gateways, route.ParentRefs, route.Hostnames, gvk.HTTPRoute, obj.Namespace)
+@@ -172,10 +270,7 @@
+ 		})
+ 	}
+
+-	name := fmt.Sprintf("%s-%s", obj.Name, constants.KubernetesGatewayName)
+-
+ 	httproutes := []*istio.HTTPRoute{}
+-	hosts := hostnameToStringList(route.Hostnames)
+ 	for _, r := range route.Rules {
+ 		// TODO: implement rewrite, timeout, mirror, corspolicy, retries
+ 		vs := &istio.HTTPRoute{
+@@ -185,22 +280,22 @@
+ 			uri, err := createURIMatch(match)
+ 			if err != nil {
+ 				reportError(err)
+-				return nil
++				return
+ 			}
+ 			headers, err := createHeadersMatch(match)
+ 			if err != nil {
+ 				reportError(err)
+-				return nil
++				return
+ 			}
+ 			qp, err := createQueryParamsMatch(match)
+ 			if err != nil {
+ 				reportError(err)
+-				return nil
++				return
+ 			}
+ 			method, err := createMethodMatch(match)
+ 			if err != nil {
+ 				reportError(err)
+-				return nil
++				return
+ 			}
+ 			vs.Match = append(vs.Match, &istio.HTTPMatchRequest{
+ 				Uri:         uri,
+@@ -219,7 +314,7 @@
+ 				mirror, err := createMirrorFilter(filter.RequestMirror, obj.Namespace, domain)
+ 				if err != nil {
+ 					reportError(err)
+-					return nil
++					return
+ 				}
+ 				vs.Mirror = mirror
+ 			default:
+@@ -227,7 +322,7 @@
+ 					Reason:  InvalidFilter,
+ 					Message: fmt.Sprintf("unsupported filter type %q", filter.Type),
+ 				})
+-				return nil
++				return
+ 			}
+ 		}
+
+@@ -255,33 +350,65 @@
+ 		route, err := buildHTTPDestination(r.BackendRefs, obj.Namespace, domain, zero, fallbackCluster)
+ 		if err != nil {
+ 			reportError(err)
+-			return nil
++			return
+ 		}
+ 		vs.Route = route
+
+ 		httproutes = append(httproutes, vs)
+ 	}
+ 	reportError(nil)
+-	gatewayNames := referencesToInternalNames(parentRefs)
+-	if len(gatewayNames) == 0 {
+-		return nil
++
++	count := 0
++	for _, parent := range filteredReferences(parentRefs) {
++		// for gateway routes, build one VS per gateway+host
++		routeMap := gatewayRoutes
++		routeKey := parent.InternalName
++		vsHosts := hostnameToStringList(route.Hostnames)
++		routes := httproutes
++		if len(routes) == 0 {
++			continue
++		}
++		if _, f := routeMap[routeKey]; !f {
++			routeMap[routeKey] = make(map[string]*config.Config)
++		}
++
++		// Create one VS per hostname with a single hostname.
++		// This ensures we can treat each hostname independently, as the spec requires
++		for _, h := range vsHosts {
++			if cfg := routeMap[routeKey][h]; cfg != nil {
++				// merge http routes
++				vs := cfg.Spec.(*istio.VirtualService)
++				vs.Http = append(vs.Http, routes...)
++				// append parents
++				cfg.Annotations[constants.InternalParentNames] = fmt.Sprintf("%s,%s/%s.%s",
++					cfg.Annotations[constants.InternalParentNames], obj.GroupVersionKind.Kind, obj.Name, obj.Namespace)
++			} else {
++				name := fmt.Sprintf("%s-%d-%s", obj.Name, count, constants.KubernetesGatewayName)
++				routeMap[routeKey][h] = &config.Config{
++					Meta: config.Meta{
++						CreationTimestamp: obj.CreationTimestamp,
++						GroupVersionKind:  gvk.VirtualService,
++						Name:              name,
++						Annotations:       routeMeta(obj),
++						Namespace:         obj.Namespace,
++						Domain:            ctx.Domain,
++					},
++					Spec: &istio.VirtualService{
++						Hosts:    []string{h},
++						Gateways: []string{parent.InternalName},
++						Http:     routes,
++					},
++				}
++				count++
++			}
++		}
+ 	}
+-	vsConfig := config.Config{
+-		Meta: config.Meta{
+-			CreationTimestamp: obj.CreationTimestamp,
+-			GroupVersionKind:  gvk.VirtualService,
+-			Name:              name,
+-			Annotations:       parentMeta(obj, nil),
+-			Namespace:         obj.Namespace,
+-			Domain:            domain,
+-		},
+-		Spec: &istio.VirtualService{
+-			Hosts:    hosts,
+-			Gateways: gatewayNames,
+-			Http:     httproutes,
+-		},
++	for _, vsByHost := range gatewayRoutes {
++		for _, cfg := range vsByHost {
++			vs := cfg.Spec.(*istio.VirtualService)
++			sortHTTPRoutes(vs.Http)
++		}
+ 	}
+-	return &vsConfig
+ }
+
+ func parentMeta(obj config.Config, sectionName *gatewayapiV1beta1.SectionName) map[string]string {
+@@ -1155,9 +1282,11 @@
+ 			}
+ 			gs.Addresses = make([]gatewayapiV1beta1.GatewayAddress, 0, len(addressesToReport))
+ 			for _, addr := range addressesToReport {
++				addrPairs := strings.Split(addr, ":")
+ 				gs.Addresses = append(gs.Addresses, gatewayapiV1beta1.GatewayAddress{
+-					Type:  &addrType,
+-					Value: addr,
++					Type: &addrType,
++					// strip the port
++					Value: addrPairs[0],
+ 				})
+ 			}
+ 			return gs
+diff -Naur istio/pilot/pkg/model/push_context.go istio-new/pilot/pkg/model/push_context.go
+--- istio/pilot/pkg/model/push_context.go	2023-11-03 17:18:56.000000000 +0800
++++ istio-new/pilot/pkg/model/push_context.go	2023-11-03 17:05:47.000000000 +0800
+@@ -841,7 +841,19 @@
+ func (ps *PushContext) VirtualServicesForGateway(proxy *Proxy, gateway string) []config.Config {
+ 	res := ps.virtualServiceIndex.privateByNamespaceAndGateway[proxy.ConfigNamespace][gateway]
+ 	res = append(res, ps.virtualServiceIndex.exportedToNamespaceByGateway[proxy.ConfigNamespace][gateway]...)
+-	res = append(res, ps.virtualServiceIndex.publicByGateway[gateway]...)
++
++	// Favor same-namespace Gateway routes, to give the "consumer override" preference.
++	// We do 2 iterations here to avoid extra allocations.
++	for _, vs := range ps.virtualServiceIndex.publicByGateway[gateway] {
++		if UseGatewaySemantics(vs) && vs.Namespace == proxy.ConfigNamespace {
++			res = append(res, vs)
++		}
++	}
++	for _, vs := range ps.virtualServiceIndex.publicByGateway[gateway] {
++		if !(UseGatewaySemantics(vs) && vs.Namespace == proxy.ConfigNamespace) {
++			res = append(res, vs)
++		}
++	}
+ 	return res
+ }
+
+diff -Naur istio/pilot/pkg/model/virtualservice.go istio-new/pilot/pkg/model/virtualservice.go
+--- istio/pilot/pkg/model/virtualservice.go	2023-11-03 17:18:55.000000000 +0800
++++ istio-new/pilot/pkg/model/virtualservice.go	2023-11-03 15:19:08.000000000 +0800
+@@ -76,6 +76,11 @@
+ }
+
+ func resolveVirtualServiceShortnames(rule *networking.VirtualService, meta config.Meta) {
++	// Kubernetes Gateway API semantics support shortnames
++	// if UseGatewaySemantics(config.Config{Meta: meta}) {
++	// 	return
++	// }
++
+ 	// resolve top level hosts
+ 	for i, h := range rule.Hosts {
+ 		rule.Hosts[i] = string(ResolveShortnameToFQDN(h, meta))
+@@ -524,3 +529,10 @@
+ 	}
+ 	return false
+ }
++
++// UseGatewaySemantics determines which logic we should use for VirtualService
++// This allows gateway-api and VS to both be represented by VirtualService, but have different
++// semantics.
++func UseGatewaySemantics(cfg config.Config) bool {
++	return cfg.Annotations[constants.InternalRouteSemantics] == constants.RouteSemanticsGateway
++}
+diff -Naur istio/pilot/pkg/networking/core/v1alpha3/route/route.go istio-new/pilot/pkg/networking/core/v1alpha3/route/route.go
+--- istio/pilot/pkg/networking/core/v1alpha3/route/route.go	2023-11-03 17:18:56.000000000 +0800
++++ istio-new/pilot/pkg/networking/core/v1alpha3/route/route.go	2023-11-03 17:05:55.000000000 +0800
+@@ -408,7 +408,6 @@
+ 			break
+ 		}
+ 	}
+-
+ 	if len(out) == 0 {
+ 		return nil, fmt.Errorf("no routes matched")
+ 	}
+@@ -493,6 +492,14 @@
+ 			},
+ 		}
+
++		if model.UseGatewaySemantics(virtualService) {
++			if uri, isPrefixReplace := cutPrefix(redirect.Uri, "%PREFIX()%"); isPrefixReplace {
++				action.Redirect.PathRewriteSpecifier = &route.RedirectAction_PrefixRewrite{
++					PrefixRewrite: uri,
++				}
++			}
++		}
++
+ 		if redirect.Scheme != "" {
+ 			action.Redirect.SchemeRewriteSpecifier = &route.RedirectAction_SchemeRedirect{SchemeRedirect: redirect.Scheme}
+ 		}
+@@ -1616,3 +1623,10 @@
+ 	isSupport = curVersion.GreaterThan(notSupportFallback)
+ 	return
+ }
++
++func cutPrefix(s, prefix string) (after string, found bool) {
++	if !strings.HasPrefix(s, prefix) {
++		return s, false
++	}
++	return s[len(prefix):], true
++}
+diff -Naur istio/pkg/config/constants/constants.go istio-new/pkg/config/constants/constants.go
+--- istio/pkg/config/constants/constants.go	2023-11-03 17:18:54.000000000 +0800
++++ istio-new/pkg/config/constants/constants.go	2023-11-03 14:29:27.000000000 +0800
+@@ -15,6 +15,12 @@
+ package constants
+
+ const (
++	InternalParentNames = "internal.istio.io/parents"
++
++	InternalRouteSemantics = "internal.istio.io/route-semantics"
++
++	RouteSemanticsGateway = "gateway"
++
+ 	// UnspecifiedIP constant for empty IP address
+ 	UnspecifiedIP = "0.0.0.0"
+