BackendConfig support for session affinity

pkg/apis/backendconfig/v1beta1/types.go

@@ -36,11 +36,13 @@ type BackendConfig struct {
 // BackendConfigSpec is the spec for a BackendConfig resource
 // +k8s:openapi-gen=true
 type BackendConfigSpec struct {
-	Iap                *IAPConfig                `json:"iap,omitempty"`
-	Cdn                *CDNConfig                `json:"cdn,omitempty"`
-	SecurityPolicy     *SecurityPolicyConfig     `json:"securityPolicy,omitempty"`
-	TimeoutSec         *int64                    `json:"timeoutSec,omitempty"`
-	ConnectionDraining *ConnectionDrainingConfig `json:"connectionDraining,omitempty"`
+	Iap                  *IAPConfig                `json:"iap,omitempty"`
+	Cdn                  *CDNConfig                `json:"cdn,omitempty"`
+	SecurityPolicy       *SecurityPolicyConfig     `json:"securityPolicy,omitempty"`
+	TimeoutSec           *int64                    `json:"timeoutSec,omitempty"`
+	ConnectionDraining   *ConnectionDrainingConfig `json:"connectionDraining,omitempty"`
+	AffinityCookieTtlSec *int64                    `json:"affinityCookieTtlSec,omitempty"`
+	SessionAffinity      string                    `json:"sessionAffinity,omitempty"`
 }
 
 // BackendConfigStatus is the status for a BackendConfig resource

pkg/backends/features/affinity.go

@@ -0,0 +1,50 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package features
+
+import (
+	"strings"
+
+	"github.com/golang/glog"
+	"k8s.io/ingress-gce/pkg/composite"
+	"k8s.io/ingress-gce/pkg/utils"
+)
+
+// EnsureAffinity reads the sessionAffinity and AffinityCookieTtlSec configuration
+// specified in the ServicePort.BackendConfig and applies it to the BackendService.
+// It returns true if there were existing settings on the BackendService
+// that were overwritten.
+func EnsureAffinity(sp utils.ServicePort, be *composite.BackendService) bool {
+	changed := false
+
+	// Should we check if specified SessionAffinity is among the currently GCP supported values?
+	// For now let's forward as is to GCP, to inherit API error message (and evolutions).
+	// Same for TTL (should be in 0-86400 range).
+	if sp.BackendConfig.Spec.SessionAffinity != "" && strings.Compare(sp.BackendConfig.Spec.SessionAffinity, be.SessionAffinity) != 0 {
+		be.SessionAffinity = sp.BackendConfig.Spec.SessionAffinity
+		glog.V(2).Infof("Updated SessionAffinity settings for service %v/%v.", sp.ID.Service.Namespace, sp.ID.Service.Name)
+		changed = true
+	}
+
+	if sp.BackendConfig.Spec.AffinityCookieTtlSec != nil && *sp.BackendConfig.Spec.AffinityCookieTtlSec != be.AffinityCookieTtlSec {
+		be.AffinityCookieTtlSec = *sp.BackendConfig.Spec.AffinityCookieTtlSec
+		glog.V(2).Infof("Updated AffinityCookieTtlSec settings for service %v/%v.", sp.ID.Service.Namespace, sp.ID.Service.Name)
+		changed = true
+	}
+
+	return changed
+}

pkg/backends/features/affinity_test.go

@@ -0,0 +1,119 @@
+/*
+Copyright 2015 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package features
+
+import (
+	"testing"
+
+	backendconfigv1beta1 "k8s.io/ingress-gce/pkg/apis/backendconfig/v1beta1"
+	"k8s.io/ingress-gce/pkg/composite"
+	"k8s.io/ingress-gce/pkg/utils"
+)
+
+var testTTL = int64(10)
+
+func TestEnsureAffinity(t *testing.T) {
+	testCases := []struct {
+		desc           string
+		sp             utils.ServicePort
+		be             *composite.BackendService
+		updateExpected bool
+	}{
+		{
+			desc: "affinity settings missing from spec, no update needed",
+			sp: utils.ServicePort{
+				BackendConfig: &backendconfigv1beta1.BackendConfig{
+					Spec: backendconfigv1beta1.BackendConfigSpec{},
+				},
+			},
+			be: &composite.BackendService{
+				SessionAffinity:      "GENERATED_COOKIE",
+				AffinityCookieTtlSec: 10,
+			},
+			updateExpected: false,
+		},
+		{
+			desc: "sessionaffinity setting differing, update needed",
+			sp: utils.ServicePort{
+				BackendConfig: &backendconfigv1beta1.BackendConfig{
+					Spec: backendconfigv1beta1.BackendConfigSpec{
+						SessionAffinity: "CLIENT_IP",
+					},
+				},
+			},
+			be: &composite.BackendService{
+				SessionAffinity: "NONE",
+			},
+			updateExpected: true,
+		},
+		{
+			desc: "affinity ttl setting differing, update needed",
+			sp: utils.ServicePort{
+				BackendConfig: &backendconfigv1beta1.BackendConfig{
+					Spec: backendconfigv1beta1.BackendConfigSpec{
+						AffinityCookieTtlSec: &testTTL,
+					},
+				},
+			},
+			be: &composite.BackendService{
+				AffinityCookieTtlSec: 20,
+			},
+			updateExpected: true,
+		},
+		{
+			desc: "sessionaffinity and ttl settings differing, update needed",
+			sp: utils.ServicePort{
+				BackendConfig: &backendconfigv1beta1.BackendConfig{
+					Spec: backendconfigv1beta1.BackendConfigSpec{
+						SessionAffinity:      "CLIENT_IP",
+						AffinityCookieTtlSec: &testTTL,
+					},
+				},
+			},
+			be: &composite.BackendService{
+				SessionAffinity:      "NONE",
+				AffinityCookieTtlSec: 20,
+			},
+			updateExpected: true,
+		},
+		{
+			desc: "affinity settings identical, no updated needed",
+			sp: utils.ServicePort{
+				BackendConfig: &backendconfigv1beta1.BackendConfig{
+					Spec: backendconfigv1beta1.BackendConfigSpec{
+						SessionAffinity:      "CLIENT_IP",
+						AffinityCookieTtlSec: &testTTL,
+					},
+				},
+			},
+			be: &composite.BackendService{
+				SessionAffinity:      "CLIENT_IP",
+				AffinityCookieTtlSec: testTTL,
+			},
+			updateExpected: false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.desc, func(t *testing.T) {
+			result := EnsureAffinity(tc.sp, tc.be)
+			if result != tc.updateExpected {
+				t.Errorf("%v: expected %v but got %v", tc.desc, tc.updateExpected, result)
+			}
+		})
+	}
+}

pkg/backends/syncer.go

@@ -114,6 +114,7 @@ func (s *backendSyncer) ensureBackendService(sp utils.ServicePort) error {
 		needUpdate = features.EnsureIAP(sp, be) || needUpdate
 		needUpdate = features.EnsureTimeout(sp, be) || needUpdate
 		needUpdate = features.EnsureDraining(sp, be) || needUpdate
+		needUpdate = features.EnsureAffinity(sp, be) || needUpdate
 	}
 
 	if needUpdate {