Files
flagger/pkg/router/istio.go
stefanprodan 45df96ff3c Format imports
2019-10-06 12:54:01 +03:00

405 lines
12 KiB
Go

package router
import (
"fmt"
"github.com/google/go-cmp/cmp"
"github.com/google/go-cmp/cmp/cmpopts"
"go.uber.org/zap"
"k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/client-go/kubernetes"
flaggerv1 "github.com/weaveworks/flagger/pkg/apis/flagger/v1alpha3"
istiov1alpha3 "github.com/weaveworks/flagger/pkg/apis/istio/v1alpha3"
clientset "github.com/weaveworks/flagger/pkg/client/clientset/versioned"
)
// IstioRouter is managing Istio virtual services
type IstioRouter struct {
kubeClient kubernetes.Interface
istioClient clientset.Interface
flaggerClient clientset.Interface
logger *zap.SugaredLogger
}
// Reconcile creates or updates the Istio virtual service and destination rules
func (ir *IstioRouter) Reconcile(canary *flaggerv1.Canary) error {
canaryName := fmt.Sprintf("%s-canary", canary.Spec.TargetRef.Name)
primaryName := fmt.Sprintf("%s-primary", canary.Spec.TargetRef.Name)
err := ir.reconcileDestinationRule(canary, canaryName)
if err != nil {
return err
}
err = ir.reconcileDestinationRule(canary, primaryName)
if err != nil {
return err
}
err = ir.reconcileVirtualService(canary)
if err != nil {
return err
}
return nil
}
func (ir *IstioRouter) reconcileDestinationRule(canary *flaggerv1.Canary, name string) error {
newSpec := istiov1alpha3.DestinationRuleSpec{
Host: name,
TrafficPolicy: canary.Spec.Service.TrafficPolicy,
}
destinationRule, err := ir.istioClient.NetworkingV1alpha3().DestinationRules(canary.Namespace).Get(name, metav1.GetOptions{})
// insert
if errors.IsNotFound(err) {
destinationRule = &istiov1alpha3.DestinationRule{
ObjectMeta: metav1.ObjectMeta{
Name: name,
Namespace: canary.Namespace,
OwnerReferences: []metav1.OwnerReference{
*metav1.NewControllerRef(canary, schema.GroupVersionKind{
Group: flaggerv1.SchemeGroupVersion.Group,
Version: flaggerv1.SchemeGroupVersion.Version,
Kind: flaggerv1.CanaryKind,
}),
},
},
Spec: newSpec,
}
_, err = ir.istioClient.NetworkingV1alpha3().DestinationRules(canary.Namespace).Create(destinationRule)
if err != nil {
return fmt.Errorf("DestinationRule %s.%s create error %v", name, canary.Namespace, err)
}
ir.logger.With("canary", fmt.Sprintf("%s.%s", canary.Name, canary.Namespace)).
Infof("DestinationRule %s.%s created", destinationRule.GetName(), canary.Namespace)
return nil
}
if err != nil {
return fmt.Errorf("DestinationRule %s.%s query error %v", name, canary.Namespace, err)
}
// update
if destinationRule != nil {
if diff := cmp.Diff(newSpec, destinationRule.Spec); diff != "" {
clone := destinationRule.DeepCopy()
clone.Spec = newSpec
_, err = ir.istioClient.NetworkingV1alpha3().DestinationRules(canary.Namespace).Update(clone)
if err != nil {
return fmt.Errorf("DestinationRule %s.%s update error %v", name, canary.Namespace, err)
}
ir.logger.With("canary", fmt.Sprintf("%s.%s", canary.Name, canary.Namespace)).
Infof("DestinationRule %s.%s updated", destinationRule.GetName(), canary.Namespace)
}
}
return nil
}
func (ir *IstioRouter) reconcileVirtualService(canary *flaggerv1.Canary) error {
targetName := canary.Spec.TargetRef.Name
// set hosts and add the ClusterIP service host if it doesn't exists
hosts := canary.Spec.Service.Hosts
var hasServiceHost bool
for _, h := range hosts {
if h == targetName || h == "*" {
hasServiceHost = true
break
}
}
if !hasServiceHost {
hosts = append(hosts, targetName)
}
// set gateways and add the mesh gateway if it doesn't exists
gateways := canary.Spec.Service.Gateways
var hasMeshGateway bool
for _, g := range gateways {
if g == "mesh" {
hasMeshGateway = true
break
}
}
// set default mesh gateway if no gateway is specified
if !hasMeshGateway && len(canary.Spec.Service.Gateways) == 0 {
gateways = append(gateways, "mesh")
}
// create destinations with primary weight 100% and canary weight 0%
primaryName := fmt.Sprintf("%s-primary", targetName)
canaryName := fmt.Sprintf("%s-canary", targetName)
canaryRoute := []istiov1alpha3.DestinationWeight{
makeDestination(canary, primaryName, 100),
makeDestination(canary, canaryName, 0),
}
newSpec := istiov1alpha3.VirtualServiceSpec{
Hosts: hosts,
Gateways: gateways,
Http: []istiov1alpha3.HTTPRoute{
{
Match: canary.Spec.Service.Match,
Rewrite: canary.Spec.Service.Rewrite,
Timeout: canary.Spec.Service.Timeout,
Retries: canary.Spec.Service.Retries,
CorsPolicy: canary.Spec.Service.CorsPolicy,
AppendHeaders: addHeaders(canary),
Route: canaryRoute,
},
},
}
if len(canary.Spec.CanaryAnalysis.Match) > 0 {
canaryMatch := mergeMatchConditions(canary.Spec.CanaryAnalysis.Match, canary.Spec.Service.Match)
newSpec.Http = []istiov1alpha3.HTTPRoute{
{
Match: canaryMatch,
Rewrite: canary.Spec.Service.Rewrite,
Timeout: canary.Spec.Service.Timeout,
Retries: canary.Spec.Service.Retries,
CorsPolicy: canary.Spec.Service.CorsPolicy,
AppendHeaders: addHeaders(canary),
Route: canaryRoute,
},
{
Match: canary.Spec.Service.Match,
Rewrite: canary.Spec.Service.Rewrite,
Timeout: canary.Spec.Service.Timeout,
Retries: canary.Spec.Service.Retries,
CorsPolicy: canary.Spec.Service.CorsPolicy,
AppendHeaders: addHeaders(canary),
Route: []istiov1alpha3.DestinationWeight{
makeDestination(canary, primaryName, 100),
},
},
}
}
virtualService, err := ir.istioClient.NetworkingV1alpha3().VirtualServices(canary.Namespace).Get(targetName, metav1.GetOptions{})
// insert
if errors.IsNotFound(err) {
virtualService = &istiov1alpha3.VirtualService{
ObjectMeta: metav1.ObjectMeta{
Name: targetName,
Namespace: canary.Namespace,
OwnerReferences: []metav1.OwnerReference{
*metav1.NewControllerRef(canary, schema.GroupVersionKind{
Group: flaggerv1.SchemeGroupVersion.Group,
Version: flaggerv1.SchemeGroupVersion.Version,
Kind: flaggerv1.CanaryKind,
}),
},
},
Spec: newSpec,
}
_, err = ir.istioClient.NetworkingV1alpha3().VirtualServices(canary.Namespace).Create(virtualService)
if err != nil {
return fmt.Errorf("VirtualService %s.%s create error %v", targetName, canary.Namespace, err)
}
ir.logger.With("canary", fmt.Sprintf("%s.%s", canary.Name, canary.Namespace)).
Infof("VirtualService %s.%s created", virtualService.GetName(), canary.Namespace)
return nil
}
if err != nil {
return fmt.Errorf("VirtualService %s.%s query error %v", targetName, canary.Namespace, err)
}
// update service but keep the original destination weights and mirror
if virtualService != nil {
if diff := cmp.Diff(
newSpec,
virtualService.Spec,
cmpopts.IgnoreFields(istiov1alpha3.DestinationWeight{}, "Weight"),
cmpopts.IgnoreFields(istiov1alpha3.HTTPRoute{}, "Mirror"),
); diff != "" {
vtClone := virtualService.DeepCopy()
vtClone.Spec = newSpec
_, err = ir.istioClient.NetworkingV1alpha3().VirtualServices(canary.Namespace).Update(vtClone)
if err != nil {
return fmt.Errorf("VirtualService %s.%s update error %v", targetName, canary.Namespace, err)
}
ir.logger.With("canary", fmt.Sprintf("%s.%s", canary.Name, canary.Namespace)).
Infof("VirtualService %s.%s updated", virtualService.GetName(), canary.Namespace)
}
}
return nil
}
// GetRoutes returns the destinations weight for primary and canary
func (ir *IstioRouter) GetRoutes(canary *flaggerv1.Canary) (
primaryWeight int,
canaryWeight int,
mirrored bool,
err error,
) {
targetName := canary.Spec.TargetRef.Name
vs := &istiov1alpha3.VirtualService{}
vs, err = ir.istioClient.NetworkingV1alpha3().VirtualServices(canary.Namespace).Get(targetName, metav1.GetOptions{})
if err != nil {
if errors.IsNotFound(err) {
err = fmt.Errorf("VirtualService %s.%s not found", targetName, canary.Namespace)
return
}
err = fmt.Errorf("VirtualService %s.%s query error %v", targetName, canary.Namespace, err)
return
}
var httpRoute istiov1alpha3.HTTPRoute
for _, http := range vs.Spec.Http {
for _, r := range http.Route {
if r.Destination.Host == fmt.Sprintf("%s-canary", targetName) {
httpRoute = http
break
}
}
}
for _, route := range httpRoute.Route {
if route.Destination.Host == fmt.Sprintf("%s-primary", targetName) {
primaryWeight = route.Weight
}
if route.Destination.Host == fmt.Sprintf("%s-canary", targetName) {
canaryWeight = route.Weight
}
}
if httpRoute.Mirror != nil && httpRoute.Mirror.Host != "" {
mirrored = true
}
if primaryWeight == 0 && canaryWeight == 0 {
err = fmt.Errorf("VirtualService %s.%s does not contain routes for %s-primary and %s-canary",
targetName, canary.Namespace, targetName, targetName)
}
return
}
// SetRoutes updates the destinations weight for primary and canary
func (ir *IstioRouter) SetRoutes(
canary *flaggerv1.Canary,
primaryWeight int,
canaryWeight int,
mirrored bool,
) error {
targetName := canary.Spec.TargetRef.Name
primaryName := fmt.Sprintf("%s-primary", targetName)
canaryName := fmt.Sprintf("%s-canary", targetName)
vs, err := ir.istioClient.NetworkingV1alpha3().VirtualServices(canary.Namespace).Get(targetName, metav1.GetOptions{})
if err != nil {
if errors.IsNotFound(err) {
return fmt.Errorf("VirtualService %s.%s not found", targetName, canary.Namespace)
}
return fmt.Errorf("VirtualService %s.%s query error %v", targetName, canary.Namespace, err)
}
vsCopy := vs.DeepCopy()
// weighted routing (progressive canary)
vsCopy.Spec.Http = []istiov1alpha3.HTTPRoute{
{
Match: canary.Spec.Service.Match,
Rewrite: canary.Spec.Service.Rewrite,
Timeout: canary.Spec.Service.Timeout,
Retries: canary.Spec.Service.Retries,
CorsPolicy: canary.Spec.Service.CorsPolicy,
AppendHeaders: addHeaders(canary),
Route: []istiov1alpha3.DestinationWeight{
makeDestination(canary, primaryName, primaryWeight),
makeDestination(canary, canaryName, canaryWeight),
},
},
}
if mirrored {
vsCopy.Spec.Http[0].Mirror = &istiov1alpha3.Destination{
Host: canaryName,
}
}
// fix routing (A/B testing)
if len(canary.Spec.CanaryAnalysis.Match) > 0 {
// merge the common routes with the canary ones
canaryMatch := mergeMatchConditions(canary.Spec.CanaryAnalysis.Match, canary.Spec.Service.Match)
vsCopy.Spec.Http = []istiov1alpha3.HTTPRoute{
{
Match: canaryMatch,
Rewrite: canary.Spec.Service.Rewrite,
Timeout: canary.Spec.Service.Timeout,
Retries: canary.Spec.Service.Retries,
CorsPolicy: canary.Spec.Service.CorsPolicy,
AppendHeaders: addHeaders(canary),
Route: []istiov1alpha3.DestinationWeight{
makeDestination(canary, primaryName, primaryWeight),
makeDestination(canary, canaryName, canaryWeight),
},
},
{
Match: canary.Spec.Service.Match,
Rewrite: canary.Spec.Service.Rewrite,
Timeout: canary.Spec.Service.Timeout,
Retries: canary.Spec.Service.Retries,
CorsPolicy: canary.Spec.Service.CorsPolicy,
AppendHeaders: addHeaders(canary),
Route: []istiov1alpha3.DestinationWeight{
makeDestination(canary, primaryName, primaryWeight),
},
},
}
}
vs, err = ir.istioClient.NetworkingV1alpha3().VirtualServices(canary.Namespace).Update(vsCopy)
if err != nil {
return fmt.Errorf("VirtualService %s.%s update failed: %v", targetName, canary.Namespace, err)
}
return nil
}
// addHeaders applies headers before forwarding a request to the destination service
// compatible with Istio 1.0.x and 1.1.0
func addHeaders(canary *flaggerv1.Canary) (headers map[string]string) {
if canary.Spec.Service.Headers != nil &&
canary.Spec.Service.Headers.Request != nil &&
len(canary.Spec.Service.Headers.Request.Add) > 0 {
headers = canary.Spec.Service.Headers.Request.Add
}
return
}
// mergeMatchConditions appends the URI match rules to canary conditions
func mergeMatchConditions(canary, defaults []istiov1alpha3.HTTPMatchRequest) []istiov1alpha3.HTTPMatchRequest {
for i := range canary {
for _, d := range defaults {
if d.Uri != nil {
canary[i].Uri = d.Uri
}
}
}
return canary
}
// makeDestination returns a an destination weight for the specified host
func makeDestination(canary *flaggerv1.Canary, host string, weight int) istiov1alpha3.DestinationWeight {
dest := istiov1alpha3.DestinationWeight{
Destination: istiov1alpha3.Destination{
Host: host,
},
Weight: weight,
}
return dest
}