Feature flag to enable/disable canary + optional prometheus install (#937)

canaryconfigmgr/canaryConfigMgr.go

@@ -19,9 +19,11 @@ package canaryconfigmgr
 import (
 	"context"
 	"fmt"
-	log "github.com/sirupsen/logrus"
+	"os"
+	"strings"
 	"time"
 
+	log "github.com/sirupsen/logrus"
 	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/fields"
@@ -45,7 +47,19 @@ type canaryConfigMgr struct {
 
 func MakeCanaryConfigMgr(fissionClient *crd.FissionClient, kubeClient *kubernetes.Clientset, crdClient *rest.RESTClient, prometheusSvc string) (*canaryConfigMgr, error) {
 	if prometheusSvc == "" {
-		return nil, fmt.Errorf("prometheus service not found, cant create canary config manager")
+		// handle a case where there is a prometheus server is already installed, try to find the service from env variable
+		envVars := os.Environ()
+		for _, envVar := range envVars {
+			if strings.Contains(envVar, "PROMETHEUS_SERVER_SERVICE_HOST") {
+				envVarSplit := strings.Split(envVar, "=")
+				prometheusSvc = envVarSplit[1]
+				break
+			}
+		}
+
+		if prometheusSvc == "" {
+			return nil, fmt.Errorf("prometheus service not found, cant create canary config manager")
+		}
 	}
 
 	configMgr := &canaryConfigMgr{

charts/fission-all/requirements.yaml

@@ -1,4 +1,5 @@
 dependencies:
   - name: prometheus
     version: 7.1.0
-    repository: https://kubernetes-charts.storage.googleapis.com
+    repository: https://kubernetes-charts.storage.googleapis.com
+    condition: prometheusDeploy

charts/fission-all/templates/_helpers.tpl

@@ -14,3 +14,20 @@ We truncate at 24 chars because some Kubernetes name fields are limited to this
 {{- $name := default .Chart.Name .Values.nameOverride -}}
 {{- printf "%s-%s" .Release.Name $name | trunc 24 | trimSuffix "-" -}}
 {{- end -}}
+
+
+{{/*
+This is a template with config parameters for optional features in fission. This gets mounted on to the controller pod
+as a config map.
+To add new features with config parameters, create a yaml block below with the feature name and define a corresponding struct in
+controller/config.go
+*/}}
+{{- define "config" -}}
+canary:
+  enabled: {{ .Values.canaryDeployment.enabled }}
+  {{- if .Values.prometheusDeploy }}
+  prometheusSvc: "http://{{ .Release.Name }}-prometheus-server.{{ .Release.Namespace }}"
+  {{- end }}
+  {{- printf "\n" -}}
+{{- end -}}
+

charts/fission-all/templates/deployment.yaml

@@ -103,6 +103,15 @@ metadata:
   name: fission-builder
   namespace: {{ .Values.builderNamespace }}
 
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: feature-config
+  namespace: {{ .Release.Namespace }}
+data:
+  "config.yaml": {{ include "config" . | b64enc }}
+
 ---
 apiVersion: extensions/v1beta1
 kind: Deployment
@@ -123,7 +132,7 @@ spec:
         image: "{{ .Values.repository }}/{{ .Values.image }}:{{ .Values.imageTag }}"
         imagePullPolicy: {{ .Values.pullPolicy }}
         command: ["/fission-bundle"]
-        args: ["--controllerPort", "8888", "--prometheusSvc", "http://{{ .Release.Name }}-prometheus-server.{{ .Release.Namespace }}"]
+        args: ["--controllerPort", "8888"]
         env:
           - name: FISSION_FUNCTION_NAMESPACE
             value: "{{ .Values.functionNamespace }}"
@@ -144,8 +153,15 @@ spec:
             port: 8888
           initialDelaySeconds: 35
           periodSeconds: 5
+        volumeMounts:
+        - name: config-volume
+          mountPath: /etc/config/config.yaml
+          subPath: config.yaml
       serviceAccount: fission-svc
-
+      volumes:
+      - name: config-volume
+        configMap:
+          name: feature-config
 ---
 apiVersion: extensions/v1beta1
 kind: Deployment

charts/fission-all/values.yaml

@@ -106,3 +106,10 @@ preUpgradeChecksImage: fission/pre-upgrade-checks
 ## if there are any pod specialization errors when a function is triggered and this flag is set to true, the error
 ## summary is returned as part of http response
 debugEnv: true
+
+## set this flag to true if prometheus needs to be deployed along with fission
+prometheusDeploy: true
+
+## set this flag to false if you dont need canary deployment feature
+canaryDeployment:
+  enabled: true

charts/fission-core/requirements.yaml

@@ -1,4 +1,5 @@
 dependencies:
   - name: prometheus
     version: 7.1.0
-    repository: https://kubernetes-charts.storage.googleapis.com
+    repository: https://kubernetes-charts.storage.googleapis.com
+    condition: prometheusDeploy

charts/fission-core/templates/_helpers.tpl

@@ -14,3 +14,18 @@ We truncate at 24 chars because some Kubernetes name fields are limited to this
 {{- $name := default .Chart.Name .Values.nameOverride -}}
 {{- printf "%s-%s" .Release.Name $name | trunc 24 | trimSuffix "-" -}}
 {{- end -}}
+
+{{/*
+This is a template with config parameters for optional features in fission. This gets mounted on to the controller pod
+as a config map.
+To add new features with config parameters, create a yaml block below with the feature name and define a corresponding struct in
+controller/config.go
+*/}}
+{{- define "config" -}}
+canary:
+  enabled: {{ .Values.canaryDeployment.enabled }}
+  {{- if .Values.prometheusDeploy }}
+  prometheusSvc: "http://{{ .Release.Name }}-prometheus-server.{{ .Release.Namespace }}"
+  {{- end }}
+  {{- printf "\n" -}}
+{{- end -}}

charts/fission-core/templates/deployment.yaml

@@ -103,6 +103,15 @@ metadata:
   name: fission-builder
   namespace: {{ .Values.builderNamespace }}
 
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: feature-config
+  namespace: {{ .Release.Namespace }}
+data:
+  "config.yaml": {{ include "config" . | b64enc }}
+
 ---
 apiVersion: extensions/v1beta1
 kind: Deployment
@@ -144,7 +153,15 @@ spec:
             port: 8888
           initialDelaySeconds: 35
           periodSeconds: 5
+        volumeMounts:
+        - name: config-volume
+          mountPath: /etc/config/config.yaml
+          subPath: config.yaml
       serviceAccount: fission-svc
+      volumes:
+      - name: config-volume
+        configMap:
+          name: feature-config
 
 ---
 apiVersion: extensions/v1beta1

charts/fission-core/values.yaml

@@ -71,4 +71,11 @@ preUpgradeChecksImage: fission/pre-upgrade-checks
 
 ## if there are any pod specialization errors when a function is triggered and this flag is set to true, the error
 ## summary is returned as part of http response
-debugEnv: true
+debugEnv: true
+
+## set this flag to true if prometheus needs to be deployed along with fission
+prometheusDeploy: true
+
+## set this flag to false if you dont need canary deployment feature
+canaryDeployment:
+  enabled: true

common.go

@@ -28,14 +28,14 @@ import (
 	"strings"
 	"syscall"
 
+	log "github.com/sirupsen/logrus"
+
 	"github.com/gorilla/handlers"
 	"github.com/imdario/mergo"
 	"github.com/mholt/archiver"
 	uuid "github.com/satori/go.uuid"
 	apiv1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-
-	"github.com/fission/fission/fission/log"
 )
 
 func UrlForFunction(name, namespace string) string {

controller/api.go

@@ -32,6 +32,7 @@ import (
 
 	"github.com/fission/fission"
 	"github.com/fission/fission/crd"
+	config "github.com/fission/fission/featureconfig"
 	"github.com/fission/fission/fission/logdb"
 )
 
@@ -53,6 +54,7 @@ type (
 		workflowApiUrl    string
 		functionNamespace string
 		useIstio          bool
+		featureConfig     *config.FeatureConfig
 	}
 
 	logDBConfig struct {
@@ -62,7 +64,7 @@ type (
 	}
 )
 
-func MakeAPI() (*API, error) {
+func MakeAPI(featureConfig *config.FeatureConfig) (*API, error) {
 	api, err := makeCRDBackedAPI()
 
 	u := os.Getenv("STORAGE_SERVICE_URL")
@@ -93,6 +95,8 @@ func MakeAPI() (*API, error) {
 		api.functionNamespace = "fission-function"
 	}
 
+	api.featureConfig = featureConfig
+
 	return api, err
 }
 

controller/api_test.go

@@ -344,7 +344,7 @@ func TestMain(m *testing.M) {
 		return
 	}
 
-	go Start(8888, "http://localhost:9090")
+	go Start(8888, true)
 
 	time.Sleep(5 * time.Second)
 	g.client = client.MakeClient("http://localhost:8888")

controller/canaryConfigApi.go

@@ -25,10 +25,16 @@ import (
 	log "github.com/sirupsen/logrus"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
+	"github.com/fission/fission"
 	"github.com/fission/fission/crd"
 )
 
 func (a *API) CanaryConfigApiCreate(w http.ResponseWriter, r *http.Request) {
+	if !a.featureConfig.CanaryConfig.IsEnabled {
+		a.respondWithError(w, fission.MakeError(http.StatusBadRequest, "Please enable canary feature while installing fission"))
+		return
+	}
+
 	body, err := ioutil.ReadAll(r.Body)
 	if err != nil {
 		a.respondWithError(w, err)
@@ -60,6 +66,11 @@ func (a *API) CanaryConfigApiCreate(w http.ResponseWriter, r *http.Request) {
 }
 
 func (a *API) CanaryConfigApiGet(w http.ResponseWriter, r *http.Request) {
+	if !a.featureConfig.CanaryConfig.IsEnabled {
+		a.respondWithError(w, fission.MakeError(http.StatusBadRequest, "Please enable canary feature while installing fission"))
+		return
+	}
+
 	vars := mux.Vars(r)
 	name := vars["canaryConfig"]
 
@@ -84,6 +95,11 @@ func (a *API) CanaryConfigApiGet(w http.ResponseWriter, r *http.Request) {
 }
 
 func (a *API) CanaryConfigApiList(w http.ResponseWriter, r *http.Request) {
+	if !a.featureConfig.CanaryConfig.IsEnabled {
+		a.respondWithError(w, fission.MakeError(http.StatusBadRequest, "Please enable canary feature while installing fission"))
+		return
+	}
+
 	ns := a.extractQueryParamFromRequest(r, "namespace")
 	if len(ns) == 0 {
 		ns = metav1.NamespaceDefault
@@ -105,6 +121,11 @@ func (a *API) CanaryConfigApiList(w http.ResponseWriter, r *http.Request) {
 }
 
 func (a *API) CanaryConfigApiUpdate(w http.ResponseWriter, r *http.Request) {
+	if !a.featureConfig.CanaryConfig.IsEnabled {
+		a.respondWithError(w, fission.MakeError(http.StatusBadRequest, "Please enable canary feature while installing fission"))
+		return
+	}
+
 	body, err := ioutil.ReadAll(r.Body)
 	if err != nil {
 		a.respondWithError(w, err)
@@ -134,6 +155,11 @@ func (a *API) CanaryConfigApiUpdate(w http.ResponseWriter, r *http.Request) {
 }
 
 func (a *API) CanaryConfigApiDelete(w http.ResponseWriter, r *http.Request) {
+	if !a.featureConfig.CanaryConfig.IsEnabled {
+		a.respondWithError(w, fission.MakeError(http.StatusBadRequest, "Please enable canary feature while installing fission"))
+		return
+	}
+
 	vars := mux.Vars(r)
 	name := vars["canaryConfig"]
 	ns := a.extractQueryParamFromRequest(r, "namespace")

controller/config.go

@@ -0,0 +1,65 @@
+/*
+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 controller
+
+import (
+	"context"
+	"fmt"
+
+	log "github.com/sirupsen/logrus"
+	"k8s.io/client-go/kubernetes"
+
+	"github.com/fission/fission/canaryconfigmgr"
+	"github.com/fission/fission/crd"
+	config "github.com/fission/fission/featureconfig"
+)
+
+func ConfigCanaryFeature(context context.Context, fissionClient *crd.FissionClient, kubeClient *kubernetes.Clientset, featureConfig *config.FeatureConfig) error {
+	// start the appropriate controller
+	if featureConfig.CanaryConfig.IsEnabled {
+		canaryCfgMgr, err := canaryconfigmgr.MakeCanaryConfigMgr(fissionClient, kubeClient, fissionClient.GetCrdClient(),
+			featureConfig.CanaryConfig.PrometheusSvc)
+		if err != nil {
+			return fmt.Errorf("failed to start canary config manager: %v", err)
+		}
+		canaryCfgMgr.Run(context)
+		log.Printf("Started canary config manager")
+	}
+
+	return nil
+}
+
+// ConfigureFeatures gets the feature config and configures the features that are enabled
+func ConfigureFeatures(context context.Context, unitTestMode bool, fissionClient *crd.FissionClient, kubeClient *kubernetes.Clientset) (*config.FeatureConfig, error) {
+	// set feature enabled to false if unitTestMode
+	if unitTestMode {
+		featureConfig := &config.FeatureConfig{}
+		return featureConfig, nil
+	}
+
+	// get the featureConfig from config map mounted onto the file system
+	featureConfig, err := config.GetFeatureConfig()
+	if err != nil {
+		log.Printf("Error getting feature config : %v", err)
+		return featureConfig, err
+	}
+
+	// configure respective features
+	// in the future when new optional features are added, we need to add corresponding feature handlers and invoke them here
+	err = ConfigCanaryFeature(context, fissionClient, kubeClient, featureConfig)
+	return featureConfig, err
+}

controller/controller.go

@@ -21,11 +21,10 @@ import (
 	"log"
 
 	"github.com/fission/fission"
-	"github.com/fission/fission/canaryconfigmgr"
 	"github.com/fission/fission/crd"
 )
 
-func Start(port int, prometheusSvc string) {
+func Start(port int, unitTestFlag bool) {
 	// setup a signal handler for SIGTERM
 	fission.SetupStackTraceHandler()
 
@@ -44,16 +43,16 @@ func Start(port int, prometheusSvc string) {
 		log.Fatalf("Error waiting for CRDs: %v", err)
 	}
 
-	// create canary config manager
-	canaryCfgMgr, err := canaryconfigmgr.MakeCanaryConfigMgr(fc, kc, fc.GetCrdClient(), prometheusSvc)
-	if err != nil {
-		log.Fatalf("Failed to start canary config manager: %v", err)
-	}
 	ctx, cancel := context.WithCancel(context.Background())
+	featureConfig, err := ConfigureFeatures(ctx, unitTestFlag, fc, kc)
+	if err != nil {
+		log.Printf("Error configuring features : %v. Proceeding without optional features", err.Error())
+		// set all features to false for the MakeApi call below
+		featureConfig.CanaryConfig.IsEnabled = false
+	}
 	defer cancel()
-	canaryCfgMgr.Run(ctx)
 
-	api, err := MakeAPI()
+	api, err := MakeAPI(featureConfig)
 	if err != nil {
 		log.Fatalf("Failed to start controller: %v", err)
 	}

featureconfig/config.go

@@ -0,0 +1,49 @@
+/*
+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 featureconfig
+
+import (
+	"encoding/base64"
+	"fmt"
+	"io/ioutil"
+
+	"github.com/ghodss/yaml"
+)
+
+// GetFeatureConfig reads the configMap file and unmarshals the config into a feature config struct
+func GetFeatureConfig() (*FeatureConfig, error) {
+	// read the file
+	b64EncodedContent, err := ioutil.ReadFile(FeatureConfigFile)
+	if err != nil {
+		return nil, fmt.Errorf("error reading YAML file %s: %v", FeatureConfigFile, err)
+	}
+
+	// b64 decode file
+	yamlContent, err := base64.StdEncoding.DecodeString(string(b64EncodedContent))
+	if err != nil {
+		return nil, fmt.Errorf("error b64 decoding the config : %v", err)
+	}
+
+	// unmarshal into feature config
+	featureConfig := &FeatureConfig{}
+	err = yaml.Unmarshal(yamlContent, featureConfig)
+	if err != nil {
+		return nil, fmt.Errorf("error unmarshalling YAML config %v", err)
+	}
+
+	return featureConfig, err
+}

featureconfig/types.go

@@ -0,0 +1,40 @@
+/*
+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 featureconfig
+
+const (
+	FeatureConfigFile = "/etc/config/config.yaml"
+)
+
+type (
+	// config.yaml contains config parameters for optional features
+	// To add new features with config parameters:
+	// 1. create a yaml block with feature name in charts/_helpers.tpl
+	// 2. define a corresponding struct with the feature config for the yaml unmarshal below
+	// 3. start the appropriate controllers needed for this feature
+
+	FeatureConfig struct {
+		// In the future more such feature configs can be added here for each optional feature
+		CanaryConfig CanaryFeatureConfig `json:"canary"`
+	}
+
+	// specific feature config
+	CanaryFeatureConfig struct {
+		IsEnabled     bool   `json:"enabled"`
+		PrometheusSvc string `json:"prometheusSvc"`
+	}
+)

fission-bundle/main.go

@@ -19,8 +19,8 @@ import (
 	"github.com/fission/fission/timer"
 )
 
-func runController(port int, prometheusSvc string) {
-	controller.Start(port, prometheusSvc)
+func runController(port int) {
+	controller.Start(port, false)
 	log.Fatalf("Error: Controller exited.")
 }
 
@@ -114,7 +114,7 @@ Use it to start one or more of the fission servers:
  backends.
 
 Usage:
-  fission-bundle --controllerPort=<port> --prometheusSvc=<url>
+  fission-bundle --controllerPort=<port>
   fission-bundle --routerPort=<port> [--executorUrl=<url>]
   fission-bundle --executorPort=<port> [--namespace=<namespace>] [--fission-namespace=<namespace>]
   fission-bundle --kubewatcher [--routerUrl=<url>]
@@ -125,7 +125,6 @@ Usage:
   fission-bundle --version
 Options:
   --controllerPort=<port>         Port that the controller should listen on.
-  --prometheusSvc=<url>           Service endpoint of prometheus server
   --routerPort=<port>             Port that the router should listen on.
   --executorPort=<port>           Port that the executor should listen on.
   --storageServicePort=<port>     Port that the storage service should listen on.
@@ -154,11 +153,10 @@ Options:
 	executorUrl := getStringArgWithDefault(arguments["--executorUrl"], "http://executor.fission")
 	routerUrl := getStringArgWithDefault(arguments["--routerUrl"], "http://router.fission")
 	storageSvcUrl := getStringArgWithDefault(arguments["--storageSvcUrl"], "http://storagesvc.fission")
-	prometheusSvcUrl := getStringArgWithDefault(arguments["--prometheusSvc"], "")
 
 	if arguments["--controllerPort"] != nil {
 		port := getPort(arguments["--controllerPort"])
-		runController(port, prometheusSvcUrl)
+		runController(port)
 	}
 
 	if arguments["--routerPort"] != nil {

fission/canaryconfig.go

@@ -106,8 +106,6 @@ func canaryConfigCreate(c *cli.Context) error {
 		},
 	}
 
-	fmt.Printf("Canary config name : %s, ns : %s, trigger : %s", canaryConfigName, ns, trigger)
-
 	_, err = client.CanaryConfigCreate(canaryCfg)
 	util.CheckErr(err, "create canary config")
 

hack/release-build.sh

@@ -241,6 +241,8 @@ build_yamls() {
         helm template ${c} -n ${c}-${version} --set serviceType=NodePort,routerServiceType=NodePort > ${c}-${version}-minikube.yaml
         # for environments support ELB
         helm template ${c} -n ${c}-${version} > ${c}-${version}.yaml
+        # for cases where prometheus installation along with fission is not preferred
+        helm template ${c} -n ${c}-${version} --set canaryDeployment.prometheusDeploy=false > ${c}-${version}-fission-only.yaml
         mv *.yaml ${BUILDDIR}/yamls/
     done