traefik/pkg/provider/kubernetes/gateway/grpcroute.go

439 lines
14 KiB
Go

package gateway
import (
"context"
"errors"
"fmt"
"net"
"strconv"
"strings"
"github.com/rs/zerolog/log"
"github.com/traefik/traefik/v3/pkg/config/dynamic"
"github.com/traefik/traefik/v3/pkg/provider"
"google.golang.org/grpc/codes"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
ktypes "k8s.io/apimachinery/pkg/types"
"k8s.io/utils/ptr"
gatev1 "sigs.k8s.io/gateway-api/apis/v1"
)
// TODO: as described in the specification https://gateway-api.sigs.k8s.io/reference/spec/#gateway.networking.k8s.io%2fv1.GRPCRoute, we should check for hostname conflicts between HTTP and GRPC routes.
func (p *Provider) loadGRPCRoutes(ctx context.Context, gatewayListeners []gatewayListener, conf *dynamic.Configuration) {
routes, err := p.client.ListGRPCRoutes()
if err != nil {
log.Ctx(ctx).Error().Err(err).Msg("Unable to list GRPCRoutes")
return
}
for _, route := range routes {
logger := log.Ctx(ctx).With().
Str("grpc_route", route.Name).
Str("namespace", route.Namespace).
Logger()
var parentStatuses []gatev1.RouteParentStatus
for _, parentRef := range route.Spec.ParentRefs {
parentStatus := &gatev1.RouteParentStatus{
ParentRef: parentRef,
ControllerName: controllerName,
Conditions: []metav1.Condition{
{
Type: string(gatev1.RouteConditionAccepted),
Status: metav1.ConditionFalse,
ObservedGeneration: route.Generation,
LastTransitionTime: metav1.Now(),
Reason: string(gatev1.RouteReasonNoMatchingParent),
},
},
}
for _, listener := range gatewayListeners {
if !matchListener(listener, route.Namespace, parentRef) {
continue
}
accepted := true
if !allowRoute(listener, route.Namespace, kindGRPCRoute) {
parentStatus.Conditions = updateRouteConditionAccepted(parentStatus.Conditions, string(gatev1.RouteReasonNotAllowedByListeners))
accepted = false
}
hostnames, ok := findMatchingHostnames(listener.Hostname, route.Spec.Hostnames)
if !ok {
parentStatus.Conditions = updateRouteConditionAccepted(parentStatus.Conditions, string(gatev1.RouteReasonNoMatchingListenerHostname))
accepted = false
}
if accepted {
// Gateway listener should have AttachedRoutes set even when Gateway has unresolved refs.
listener.Status.AttachedRoutes++
// Only consider the route attached if the listener is in an "attached" state.
if listener.Attached {
parentStatus.Conditions = updateRouteConditionAccepted(parentStatus.Conditions, string(gatev1.RouteReasonAccepted))
}
}
routeConf, resolveRefCondition := p.loadGRPCRoute(logger.WithContext(ctx), listener, route, hostnames)
if accepted && listener.Attached {
mergeHTTPConfiguration(routeConf, conf)
}
parentStatus.Conditions = upsertRouteConditionResolvedRefs(parentStatus.Conditions, resolveRefCondition)
}
parentStatuses = append(parentStatuses, *parentStatus)
}
status := gatev1.GRPCRouteStatus{
RouteStatus: gatev1.RouteStatus{
Parents: parentStatuses,
},
}
if err := p.client.UpdateGRPCRouteStatus(ctx, ktypes.NamespacedName{Namespace: route.Namespace, Name: route.Name}, status); err != nil {
logger.Warn().
Err(err).
Msg("Unable to update GRPCRoute status")
}
}
}
func (p *Provider) loadGRPCRoute(ctx context.Context, listener gatewayListener, route *gatev1.GRPCRoute, hostnames []gatev1.Hostname) (*dynamic.Configuration, metav1.Condition) {
conf := &dynamic.Configuration{
HTTP: &dynamic.HTTPConfiguration{
Routers: make(map[string]*dynamic.Router),
Middlewares: make(map[string]*dynamic.Middleware),
Services: make(map[string]*dynamic.Service),
ServersTransports: make(map[string]*dynamic.ServersTransport),
},
}
condition := metav1.Condition{
Type: string(gatev1.RouteConditionResolvedRefs),
Status: metav1.ConditionTrue,
ObservedGeneration: route.Generation,
LastTransitionTime: metav1.Now(),
Reason: string(gatev1.RouteConditionResolvedRefs),
}
for ri, routeRule := range route.Spec.Rules {
// Adding the gateway desc and the entryPoint desc prevents overlapping of routers build from the same routes.
routeKey := provider.Normalize(fmt.Sprintf("%s-%s-%s-%s-%d", route.Namespace, route.Name, listener.GWName, listener.EPName, ri))
matches := routeRule.Matches
if len(matches) == 0 {
matches = []gatev1.GRPCRouteMatch{{}}
}
for _, match := range matches {
rule, priority := buildGRPCMatchRule(hostnames, match)
router := dynamic.Router{
RuleSyntax: "v3",
Rule: rule,
Priority: priority,
EntryPoints: []string{listener.EPName},
}
if listener.Protocol == gatev1.HTTPSProtocolType {
router.TLS = &dynamic.RouterTLSConfig{}
}
var err error
routerName := makeRouterName(rule, routeKey)
router.Middlewares, err = p.loadGRPCMiddlewares(conf, route.Namespace, routerName, routeRule.Filters)
switch {
case err != nil:
log.Ctx(ctx).Error().Err(err).Msg("Unable to load GRPC route filters")
errWrrName := routerName + "-err-wrr"
conf.HTTP.Services[errWrrName] = &dynamic.Service{
Weighted: &dynamic.WeightedRoundRobin{
Services: []dynamic.WRRService{
{
Name: "invalid-grpcroute-filter",
GRPCStatus: &dynamic.GRPCStatus{
Code: codes.Unavailable,
Msg: "Service Unavailable",
},
Weight: ptr.To(1),
},
},
},
}
router.Service = errWrrName
default:
var serviceCondition *metav1.Condition
router.Service, serviceCondition = p.loadGRPCService(conf, routeKey, routeRule, route)
if serviceCondition != nil {
condition = *serviceCondition
}
}
conf.HTTP.Routers[routerName] = &router
}
}
return conf, condition
}
func (p *Provider) loadGRPCService(conf *dynamic.Configuration, routeKey string, routeRule gatev1.GRPCRouteRule, route *gatev1.GRPCRoute) (string, *metav1.Condition) {
name := routeKey + "-wrr"
if _, ok := conf.HTTP.Services[name]; ok {
return name, nil
}
var wrr dynamic.WeightedRoundRobin
var condition *metav1.Condition
for _, backendRef := range routeRule.BackendRefs {
svcName, svc, errCondition := p.loadGRPCBackendRef(route, backendRef)
weight := ptr.To(int(ptr.Deref(backendRef.Weight, 1)))
if errCondition != nil {
condition = errCondition
wrr.Services = append(wrr.Services, dynamic.WRRService{
Name: svcName,
GRPCStatus: &dynamic.GRPCStatus{
Code: codes.Unavailable,
Msg: "Service Unavailable",
},
Weight: weight,
})
continue
}
if svc != nil {
conf.HTTP.Services[svcName] = svc
}
wrr.Services = append(wrr.Services, dynamic.WRRService{
Name: svcName,
Weight: weight,
})
}
conf.HTTP.Services[name] = &dynamic.Service{Weighted: &wrr}
return name, condition
}
func (p *Provider) loadGRPCBackendRef(route *gatev1.GRPCRoute, backendRef gatev1.GRPCBackendRef) (string, *dynamic.Service, *metav1.Condition) {
kind := ptr.Deref(backendRef.Kind, kindService)
group := groupCore
if backendRef.Group != nil && *backendRef.Group != "" {
group = string(*backendRef.Group)
}
namespace := route.Namespace
if backendRef.Namespace != nil && *backendRef.Namespace != "" {
namespace = string(*backendRef.Namespace)
}
serviceName := provider.Normalize(namespace + "-" + string(backendRef.Name))
if group != groupCore || kind != kindService {
return serviceName, nil, &metav1.Condition{
Type: string(gatev1.RouteConditionResolvedRefs),
Status: metav1.ConditionFalse,
ObservedGeneration: route.Generation,
LastTransitionTime: metav1.Now(),
Reason: string(gatev1.RouteReasonInvalidKind),
Message: fmt.Sprintf("Cannot load GRPCBackendRef %s/%s/%s/%s: only Kubernetes services are supported", group, kind, namespace, backendRef.Name),
}
}
if err := p.isReferenceGranted(kindGRPCRoute, route.Namespace, group, string(kind), string(backendRef.Name), namespace); err != nil {
return serviceName, nil, &metav1.Condition{
Type: string(gatev1.RouteConditionResolvedRefs),
Status: metav1.ConditionFalse,
ObservedGeneration: route.Generation,
LastTransitionTime: metav1.Now(),
Reason: string(gatev1.RouteReasonRefNotPermitted),
Message: fmt.Sprintf("Cannot load GRPCBackendRef %s/%s/%s/%s: %s", group, kind, namespace, backendRef.Name, err),
}
}
port := ptr.Deref(backendRef.Port, gatev1.PortNumber(0))
if port == 0 {
return serviceName, nil, &metav1.Condition{
Type: string(gatev1.RouteConditionResolvedRefs),
Status: metav1.ConditionFalse,
ObservedGeneration: route.Generation,
LastTransitionTime: metav1.Now(),
Reason: string(gatev1.RouteReasonUnsupportedProtocol),
Message: fmt.Sprintf("Cannot load GRPCBackendRef %s/%s/%s/%s port is required", group, kind, namespace, backendRef.Name),
}
}
portStr := strconv.FormatInt(int64(port), 10)
serviceName = provider.Normalize(serviceName + "-" + portStr)
lb, err := p.loadGRPCServers(namespace, backendRef)
if err != nil {
return serviceName, nil, &metav1.Condition{
Type: string(gatev1.RouteConditionResolvedRefs),
Status: metav1.ConditionFalse,
ObservedGeneration: route.Generation,
LastTransitionTime: metav1.Now(),
Reason: string(gatev1.RouteReasonBackendNotFound),
Message: fmt.Sprintf("Cannot load GRPCBackendRef %s/%s/%s/%s: %s", group, kind, namespace, backendRef.Name, err),
}
}
return serviceName, &dynamic.Service{LoadBalancer: lb}, nil
}
func (p *Provider) loadGRPCMiddlewares(conf *dynamic.Configuration, namespace, routerName string, filters []gatev1.GRPCRouteFilter) ([]string, error) {
middlewares := make(map[string]*dynamic.Middleware)
for i, filter := range filters {
name := fmt.Sprintf("%s-%s-%d", routerName, strings.ToLower(string(filter.Type)), i)
switch filter.Type {
case gatev1.GRPCRouteFilterRequestHeaderModifier:
middlewares[name] = createRequestHeaderModifier(filter.RequestHeaderModifier)
case gatev1.GRPCRouteFilterExtensionRef:
name, middleware, err := p.loadHTTPRouteFilterExtensionRef(namespace, filter.ExtensionRef)
if err != nil {
return nil, fmt.Errorf("loading ExtensionRef filter %s: %w", filter.Type, err)
}
middlewares[name] = middleware
default:
// As per the spec: https://gateway-api.sigs.k8s.io/api-types/httproute/#filters-optional
// In all cases where incompatible or unsupported filters are
// specified, implementations MUST add a warning condition to
// status.
return nil, fmt.Errorf("unsupported filter %s", filter.Type)
}
}
var middlewareNames []string
for name, middleware := range middlewares {
if middleware != nil {
conf.HTTP.Middlewares[name] = middleware
}
middlewareNames = append(middlewareNames, name)
}
return middlewareNames, nil
}
func (p *Provider) loadGRPCServers(namespace string, backendRef gatev1.GRPCBackendRef) (*dynamic.ServersLoadBalancer, error) {
if backendRef.Port == nil {
return nil, errors.New("port is required for Kubernetes Service reference")
}
service, exists, err := p.client.GetService(namespace, string(backendRef.Name))
if err != nil {
return nil, fmt.Errorf("getting service: %w", err)
}
if !exists {
return nil, errors.New("service not found")
}
var svcPort *corev1.ServicePort
for _, p := range service.Spec.Ports {
if p.Port == int32(*backendRef.Port) {
svcPort = &p
break
}
}
if svcPort == nil {
return nil, fmt.Errorf("service port %d not found", *backendRef.Port)
}
endpointSlices, err := p.client.ListEndpointSlicesForService(namespace, string(backendRef.Name))
if err != nil {
return nil, fmt.Errorf("getting endpointslices: %w", err)
}
if len(endpointSlices) == 0 {
return nil, errors.New("endpointslices not found")
}
lb := &dynamic.ServersLoadBalancer{}
lb.SetDefaults()
addresses := map[string]struct{}{}
for _, endpointSlice := range endpointSlices {
var port int32
for _, p := range endpointSlice.Ports {
if svcPort.Name == *p.Name {
port = *p.Port
break
}
}
if port == 0 {
continue
}
for _, endpoint := range endpointSlice.Endpoints {
if endpoint.Conditions.Ready == nil || !*endpoint.Conditions.Ready {
continue
}
for _, address := range endpoint.Addresses {
if _, ok := addresses[address]; ok {
continue
}
addresses[address] = struct{}{}
lb.Servers = append(lb.Servers, dynamic.Server{
URL: fmt.Sprintf("h2c://%s", net.JoinHostPort(address, strconv.Itoa(int(port)))),
})
}
}
}
return lb, nil
}
func buildGRPCMatchRule(hostnames []gatev1.Hostname, match gatev1.GRPCRouteMatch) (string, int) {
var matchRules []string
methodRule := buildGRPCMethodRule(match.Method)
matchRules = append(matchRules, methodRule)
headerRules := buildGRPCHeaderRules(match.Headers)
matchRules = append(matchRules, headerRules...)
matchRulesStr := strings.Join(matchRules, " && ")
hostRule, priority := buildHostRule(hostnames)
if hostRule == "" {
return matchRulesStr, len(matchRulesStr)
}
return hostRule + " && " + matchRulesStr, priority + len(matchRulesStr)
}
func buildGRPCMethodRule(method *gatev1.GRPCMethodMatch) string {
if method == nil {
return "PathPrefix(`/`)"
}
sExpr := "[^/]+"
if s := ptr.Deref(method.Service, ""); s != "" {
sExpr = s
}
mExpr := "[^/]+"
if m := ptr.Deref(method.Method, ""); m != "" {
mExpr = m
}
return fmt.Sprintf("PathRegexp(`/%s/%s`)", sExpr, mExpr)
}
func buildGRPCHeaderRules(headers []gatev1.GRPCHeaderMatch) []string {
var rules []string
for _, header := range headers {
switch ptr.Deref(header.Type, gatev1.HeaderMatchExact) {
case gatev1.HeaderMatchExact:
rules = append(rules, fmt.Sprintf("Header(`%s`,`%s`)", header.Name, header.Value))
case gatev1.HeaderMatchRegularExpression:
rules = append(rules, fmt.Sprintf("HeaderRegexp(`%s`,`%s`)", header.Name, header.Value))
}
}
return rules
}