Run canary config server separate from controller (#2617)

* add canary config server
* remove the canary config code from the controller
* remove port exposure for canary config

pkg/canaryconfigmgr/canaryConfigMgr.go

@@ -32,6 +32,7 @@ import (
 	k8sCache "k8s.io/client-go/tools/cache"
 
 	fv1 "github.com/fission/fission/pkg/apis/core/v1"
+	"github.com/fission/fission/pkg/crd"
 	"github.com/fission/fission/pkg/generated/clientset/versioned"
 	"github.com/fission/fission/pkg/utils"
 )
@@ -550,3 +551,18 @@ func getEnvValue(envVar string) string {
 	envVarSplit := strings.Split(envVar, "=")
 	return envVarSplit[1]
 }
+
+func StartCanaryServer(ctx context.Context, logger *zap.Logger, unitTestFlag bool) error {
+	cLogger := logger.Named("CanaryServer")
+
+	fc, kc, _, _, err := crd.MakeFissionClient()
+	if err != nil {
+		cLogger.Fatal("failed to connect to k8s API", zap.Error(err))
+	}
+
+	err = ConfigureFeatures(ctx, cLogger, unitTestFlag, fc, kc)
+	if err != nil {
+		cLogger.Error("error configuring features - proceeding without optional features", zap.Error(err))
+	}
+	return err
+}

pkg/canaryconfigmgr/config.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2018 The Fission 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 canaryconfigmgr
+
+import (
+	"context"
+
+	"github.com/pkg/errors"
+	"go.uber.org/zap"
+	"k8s.io/client-go/kubernetes"
+
+	config "github.com/fission/fission/pkg/featureconfig"
+	"github.com/fission/fission/pkg/generated/clientset/versioned"
+)
+
+// ConfigureFeatures gets the feature config and configures the features that are enabled
+func ConfigureFeatures(ctx context.Context, logger *zap.Logger, unitTestMode bool, fissionClient versioned.Interface, kubeClient kubernetes.Interface) error {
+	// set feature enabled to false if unitTestMode
+	if unitTestMode {
+		return nil
+	}
+
+	// get the featureConfig from config map mounted onto the file system
+	featureConfig, err := config.GetFeatureConfig()
+	if err != nil {
+		logger.Error("error getting feature config", zap.Error(err))
+		return err
+	}
+
+	// configure respective features
+	// in the future when new optional features are added, we need to add corresponding feature handlers and invoke them here
+	canaryCfgMgr, err := MakeCanaryConfigMgr(ctx, logger, fissionClient, kubeClient, featureConfig.CanaryConfig.PrometheusSvc)
+	if err != nil {
+		return errors.Wrap(err, "failed to start canary config manager")
+	}
+	canaryCfgMgr.Run(ctx)
+
+	return err
+}

pkg/controller/api.go

@@ -67,7 +67,7 @@ type (
 	}
 )
 
-func MakeAPI(logger *zap.Logger, featureStatus map[string]string) (*API, error) {
+func MakeAPI(logger *zap.Logger) (*API, error) {
 	api, err := makeCRDBackedAPI(logger)
 
 	u := os.Getenv("STORAGE_SERVICE_URL")
@@ -98,8 +98,6 @@ func MakeAPI(logger *zap.Logger, featureStatus map[string]string) (*API, error)
 		api.functionNamespace = "fission-function"
 	}
 
-	api.featureStatus = featureStatus
-
 	return api, err
 }
 

pkg/controller/controller.go

@@ -27,7 +27,7 @@ import (
 func Start(ctx context.Context, logger *zap.Logger, port int, unitTestFlag bool) {
 	cLogger := logger.Named("controller")
 
-	fc, kc, apiExtClient, _, err := crd.MakeFissionClient()
+	fc, _, apiExtClient, _, err := crd.MakeFissionClient()
 	if err != nil {
 		cLogger.Fatal("failed to connect to k8s API", zap.Error(err))
 	}
@@ -42,12 +42,7 @@ func Start(ctx context.Context, logger *zap.Logger, port int, unitTestFlag bool)
 		cLogger.Fatal("error waiting for CRDs", zap.Error(err))
 	}
 
-	featureStatus, err := ConfigureFeatures(ctx, cLogger, unitTestFlag, fc, kc)
-	if err != nil {
-		cLogger.Error("error configuring features - proceeding without optional features", zap.Error(err))
-	}
-
-	api, err := MakeAPI(cLogger, featureStatus)
+	api, err := MakeAPI(cLogger)
 	if err != nil {
 		cLogger.Fatal("failed to start controller", zap.Error(err))
 	}