NK-9: Merged Webhook server and Policy controller. Added logger for controller.

.gitignore

@@ -1,3 +1,6 @@
 vendor
 pkg/client
 pkg/apis/policy/v1alpha1/zz_generated.deepcopy.go
+certs
+kube-policy
+Gopkg.lock

README.md

@@ -40,7 +40,7 @@ If you don't want to use SSH, you just can clone repo with git, but ensure that
 ## Restore dependencies
 
 Navigate to kube-policy project dir and execute:
-`dep restore`
+`dep ensure`
 This will install necessary dependencies described in README.md
 
 # Contributing

controller/controller.go

@@ -2,36 +2,36 @@ package controller
 
 import (
     "time"
-    "fmt"
+    "log"
 
-    "k8s.io/sample-controller/pkg/signals"
     "k8s.io/client-go/tools/clientcmd"
     "k8s.io/apimachinery/pkg/labels"
     "k8s.io/client-go/tools/cache"
 
-    clientset "nirmata/kube-policy/pkg/client/clientset/versioned"
-    informers "nirmata/kube-policy/pkg/client/informers/externalversions"
-    lister "nirmata/kube-policy/pkg/client/listers/policy/v1alpha1"
-    types "nirmata/kube-policy/pkg/apis/policy/v1alpha1"
+    clientset "github.com/nirmata/kube-policy/pkg/client/clientset/versioned"
+    informers "github.com/nirmata/kube-policy/pkg/client/informers/externalversions"
+    lister "github.com/nirmata/kube-policy/pkg/client/listers/policy/v1alpha1"
+    types "github.com/nirmata/kube-policy/pkg/apis/policy/v1alpha1"
 )
 
 // Controller for CRD
 type Controller struct {
     policyInformerFactory informers.SharedInformerFactory
     policyLister lister.PolicyLister
+    logger *log.Logger
 }
 
 // NewController from cmd args
-func NewController(masterURL, kubeconfigPath string) (*Controller, error) {
+func NewController(masterURL, kubeconfigPath string, logger *log.Logger) (*Controller, error) {
     cfg, err := clientcmd.BuildConfigFromFlags(masterURL, kubeconfigPath)
     if err != nil {
-        fmt.Printf("Error building kubeconfig: %v\n", err)
+        logger.Printf("Error building kubeconfig: %v\n", err)
         return nil, err
     }
 
     policyClientset, err := clientset.NewForConfig(cfg)
     if err != nil {
-        fmt.Printf("Error building policy clientset: %v\n", err)
+        logger.Printf("Error building policy clientset: %v\n", err)
         return nil, err
     }
 
@@ -53,15 +53,8 @@ func NewController(masterURL, kubeconfigPath string) (*Controller, error) {
 }
 
 // Run is main controller thread
-func (c *Controller) Run() error {
-    stopCh := signals.SetupSignalHandler()
+func (c *Controller) Run(stopCh <-chan struct{}) {
     c.policyInformerFactory.Start(stopCh)
-
-    fmt.Println("Running controller...")
-    <-stopCh
-    fmt.Println("\nShutting down controller...")
-
-    return nil
 }
 
 // GetPolicies retrieves all policy resources
@@ -85,24 +78,24 @@ func (c *Controller) GetPolicies() ([]*types.Policy, error) {
 
 func (c *Controller) createPolicyHandler(resource interface{}) {
     key := c.getResourceKey(resource)
-    fmt.Printf("Created policy: %s\n", key)
+    c.logger.Printf("Created policy: %s\n", key)
 }
 
 func (c *Controller) updatePolicyHandler(oldResource, newResource interface{}) {
     oldKey := c.getResourceKey(oldResource)
     newKey := c.getResourceKey(newResource)
 
-    fmt.Printf("Updated policy from %s to %s\n", oldKey, newKey)
+    c.logger.Printf("Updated policy from %s to %s\n", oldKey, newKey)
 }
 
 func (c *Controller) deletePolicyHandler(resource interface{}) {
     key := c.getResourceKey(resource)
-    fmt.Printf("Deleted policy: %s\n", key)
+    c.logger.Printf("Deleted policy: %s\n", key)
 }
 
 func (c *Controller) getResourceKey(resource interface{}) string {    
     if key, err := cache.MetaNamespaceKeyFunc(resource); err != nil {
-        fmt.Printf("Error retrieving policy key: %v\n", err)
+        c.logger.Printf("Error retrieving policy key: %v\n", err)
         return ""
     } else {
         return key

crd/MutatingWebhookConfiguration.yaml

@@ -0,0 +1,19 @@
+apiVersion: admissionregistration.k8s.io/v1beta1
+kind: MutatingWebhookConfiguration
+metadata:
+  name: nirmata-kube-policy-webhook-cfg
+  labels:
+    app: kube-policy
+webhooks:
+  - name: webhook.nirmata.kube-policy
+    clientConfig:
+      service:
+        name: kube-policy-svc
+        namespace: default
+        path: "/mutate"
+      caBundle: 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
+    rules:
+      - operations: [ "CREATE" ]
+        resources: [ "*/*" ]
+        apiGroups: [ "*" ]
+        apiVersions: [ "*" ]

crd/MutatingWebhookConfiguration_local.yaml

@@ -0,0 +1,15 @@
+apiVersion: admissionregistration.k8s.io/v1beta1
+kind: MutatingWebhookConfiguration
+metadata:
+  name: nirmata-kube-policy-webhook-cfg
+  labels:
+    app: kube-policy
+webhooks:
+  - name: webhook.nirmata.kube-policy
+    clientConfig:
+      url: "https://localhost/mutate"
+    rules:
+      - operations: [ "CREATE" ]
+        resources: [ "*/*" ]
+        apiGroups: [ "*" ]
+        apiVersions: [ "*" ]

crd/crd.yaml

@@ -8,9 +8,8 @@ spec:
     - name: v1alpha1
       served: true
       storage: true
-  scope: Namespaced
+  scope: Cluster
   names:
     kind: Policy
     plural: policies
     singular: policy
-  version: v1alpha1

crd/deployment.yaml

@@ -0,0 +1,28 @@
+apiVersion: extensions/v1beta1
+kind: Deployment
+metadata:
+  name: kube-policy-deployment
+  labels:
+    app: kube-policy
+spec:
+  replicas: 1
+  template:
+    metadata:
+      labels:
+        app: kube-policy
+    spec:
+      containers:
+        - name: kube-policy
+          image: nirmata/kube-policy:latest
+          imagePullPolicy: IfNotPresent
+          args:
+            - -cert=/etc/kube-policy/certs/server.crt
+            - -key=/etc/kube-policy/certs/server-key.pem
+          volumeMounts:
+            - name: kube-policy-certs
+              mountPath: /etc/kube-policy/certs
+              readOnly: true
+      volumes:
+        - name: kube-policy-certs
+          secret:
+            secretName: kube-policy-secret

crd/service.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: kube-policy-svc
+  labels:
+    app: kube-policy
+spec:
+  ports:
+  - port: 443
+    targetPort: 443
+  selector:
+    app: kube-policy

main.go

@@ -1,33 +1,59 @@
 package main
 
 import (
+    "log"
+    "os"
     "flag"
     "fmt"
 
-    controller "nirmata/kube-policy/controller"
+    "github.com/nirmata/kube-policy/controller"
+    "github.com/nirmata/kube-policy/server"
+    
+    "k8s.io/sample-controller/pkg/signals"
 )
 
 var (
     masterURL  string
     kubeconfig string
+    cert       string
+    key        string
 )
 
 func main() {
 	flag.Parse()
 
-    controller, err := controller.NewController(masterURL, kubeconfig)
+	if cert == "" || key == "" {
+		log.Fatal("TLS certificate or/and key is not set")
+	}
+
+    httpLogger := log.New(os.Stdout, "http: ", log.LstdFlags|log.Lshortfile)
+    crdcLogger := log.New(os.Stdout, "crdc: ", log.LstdFlags|log.Lshortfile)
+
+	server := server.NewWebhookServer(cert, key, httpLogger)
+	server.RunAsync()
+
+    controller, err := controller.NewController(masterURL, kubeconfig, crdcLogger)
     if err != nil {
         fmt.Printf("Error creating Controller! Error: %s\n", err)
         return
     }
 
-    err = controller.Run()
+    stopCh := signals.SetupSignalHandler()
+    controller.Run(stopCh)
+
     if err != nil {
         fmt.Printf("Error running Controller! Error: %s\n", err)
     }
+
+    fmt.Printf("Policy Controller has started")
+    <-stopCh
+    server.Stop()
+	fmt.Printf("Policy Controller has stopped")
 }
 
 func init() {
     flag.StringVar(&kubeconfig, "kubeconfig", "", "Path to a kubeconfig. Only required if out-of-cluster.")
     flag.StringVar(&masterURL, "master", "", "The address of the Kubernetes API server. Overrides any value in kubeconfig. Only required if out-of-cluster.")
+    flag.StringVar(&cert, "cert", "", "TLS certificate used in connection with cluster.")
+    flag.StringVar(&key, "key", "", "Key, used in TLS connection.")
 }

pkg/apis/policy/v1alpha1/register.go

@@ -5,7 +5,7 @@ import (
     "k8s.io/apimachinery/pkg/runtime"
     "k8s.io/apimachinery/pkg/runtime/schema"
          
-        "nirmata/kube-policy/pkg/apis/policy"
+    "github.com/nirmata/kube-policy/pkg/apis/policy"
 )
 
 // SchemeGroupVersion is group version used to register these objects

pkg/apis/policy/v1alpha1/types.go

@@ -26,7 +26,7 @@ type PolicySpec struct {
 type PolicyRule struct {
     Resource    PolicyResource          `json:"resource"`          
     Patches     []PolicyPatch           `json:"patches"`
-    Generator   *PolicyConfigGenerator  `json:"generator"`
+    Generators  []PolicyConfigGenerator `json:"generator"`
 }
 
 // PolicyResource describes the resource rule applied to
@@ -47,7 +47,7 @@ type PolicyPatch struct {
 type PolicyConfigGenerator struct {
     Name        string                  `json:"name"`
     CopyFrom    *PolicyCopyFrom         `json:"copyFrom"`
-    Data        *map[string]string      `json:"data"`
+    Data        map[string]string       `json:"data"`
 }
 
 // PolicyCopyFrom is TODO

scripts/README.md

@@ -0,0 +1,25 @@
+Use these scripts to prepare the controller for work.
+All these scripts should be launched from the root folder of the project, for example:
+`scripts/compile-image.sh`
+
+### compile-image.sh ###
+Compiles the project to go executable, generates docker image and pushes it to the repo. Has no arguments.
+
+### generate-server-cert.sh ###
+Generates TLS certificate and key that used by webhook server. Example:
+`scripts/generate-server-cert.sh --service=kube-policy-svc --namespace=my_namespace --serverIp=192.168.10.117`
+* `--service` identifies the service for in-cluster webhook server. Do not specify it if you plan to run webhook server outside the cluster.
+* `--namespace` identifies the namespace for in-cluster webhook server. Default value is "default".
+* `--serverIp` is the IP of master node, it can be found in `~/.kube/config`: clusters.cluster[0].server. **The default is hardcoded value**, so you should explicitly specify it.
+
+### deploy-controller.sh ###
+Prepares controller for current environment in 1 of 2 possible modes: free (local) and in-cluster. Usage:
+`scripts/deploy-controller.sh --namespace=my_namespace --serverIp=192.168.10.117`
+* --namespace identifies the namespace for in-cluster webhook server. Do not specify it if you plan to run webhook server outside the cluster.
+* --serverIp is the IP of master node, means the same as for `generate-server-cert.sh`.
+
+### test-web-hook.sh ###
+Quickly creates and deletes test config map. If your webhook server is running, you should see the corresponding output from it. Use this script after `deploy-controller.sh`.
+
+### update-codegen.sh ###
+Generates additional code for controller object. You should resolve all dependencies before using it, see main Readme for details.

scripts/compile-image.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+hub_user_name="nirmata"
+project_name="kube-policy"
+version="latest"
+
+echo "# Ensuring Go dependencies..."
+#dep ensure || exit 2
+
+echo "# Building executable ${project_name}..."
+CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o ${project_name} . || exit 3
+
+echo "# Building docker image ${hub_user_name}/${project_name}:${version}"
+cat <<EOF > Dockerfile
+FROM alpine:latest
+WORKDIR ~/
+ADD ${project_name} ./${project_name}
+ENTRYPOINT ["./${project_name}"]
+EOF
+tag="${hub_user_name}/${project_name}:${version}"
+docker build --no-cache -t "${tag}" . || exit 4
+
+echo "# Pushing image to repository..."
+docker push "${tag}" || exit 5

scripts/deploy-controller.sh

@@ -0,0 +1,64 @@
+#!/bin/bash
+
+for i in "$@"
+do
+case $i in
+    --namespace=*)
+    namespace="${i#*=}"
+    shift
+    ;;
+    --serverIp=*)
+    serverIp="${i#*=}"
+    shift
+    ;;
+esac
+done
+
+if [ -z "${serverIp}" ]; then
+  # This is the standard IP of minikube
+  serverIp="192.168.10.117" #TODO: ! Read it from ~/.kube/config !
+fi
+
+hub_user_name="nirmata"
+project_name="kube-policy"
+
+service_name="${project_name}-svc"
+echo "Generating certificate for the service ${service_name}..."
+
+certsGenerator="./scripts/generate-server-cert.sh"
+chmod +x "${certsGenerator}"
+
+if [ -z "${namespace}" ]; then # controller is launched locally
+
+  ${certsGenerator} "--serverIp=${serverIp}" || exit 2
+
+  echo "Applying webhook..."
+  kubectl delete -f crd/MutatingWebhookConfiguration_local.yaml
+  kubectl create -f crd/MutatingWebhookConfiguration_local.yaml || exit 3
+
+  echo -e "\n### You can build and run kube-policy project locally.\n### To check its work, run it with parameters -cert and -key, which contain generated TLS certificate and key (see their paths in log above)."
+
+else # controller is launched within a cluster
+
+  ${certsGenerator} "--service=${service_name}" "--namespace=${namespace}" "--serverIp=${serverIp}" || exit 2
+
+  secret_name="${project_name}-secret"
+  echo "Generating secret ${secret_name}..."
+  kubectl delete secret "${secret_name}" 2>/dev/null
+  kubectl create secret generic ${secret_name} --namespace ${namespace} --from-file=./certs || exit 3
+
+  echo "Creating the service ${service_name}..."
+  kubectl delete -f crd/service.yaml
+  kubectl create -f crd/service.yaml || exit 4
+
+  echo "Creating deployment..."
+  kubectl delete -f crd/deployment.yaml
+  kubectl create -f crd/deployment.yaml || exit 5
+
+  echo "Applying webhook..."
+  kubectl delete -f crd/MutatingWebhookConfiguration.yaml
+  kubectl create -f crd/MutatingWebhookConfiguration.yaml || exit 3
+
+  echo -e "\n### Controller is running in cluster.\n### You can use compile-image.sh to rebuild its image and then the current script to redeploy the controller.\n### Check its work by 'kubectl logs <controller_pod> command'"
+
+fi

scripts/generate-server-cert.sh

@@ -0,0 +1,89 @@
+#!/bin/bash
+
+for i in "$@"
+do
+case $i in
+    --service=*)
+    service="${i#*=}"
+    shift
+    ;;
+    --namespace=*)
+    namespace="${i#*=}"
+    shift
+    ;;
+    --serverIp=*)
+    serverIp="${i#*=}"
+    shift
+    ;;
+esac
+done
+
+if [ -z "${namespace}" ]; then
+  namespace="default"
+fi
+
+echo "service is $service"
+echo "namespace is $namespace"
+echo "serverIp is $serverIp"
+
+destdir="certs"
+if [ ! -d "$destdir" ]; then
+  mkdir ${destdir} || exit 1
+fi
+tmpdir=$(mktemp -d)
+
+cat <<EOF >> ${tmpdir}/csr.conf
+[req]
+req_extensions = v3_req
+distinguished_name = req_distinguished_name
+[req_distinguished_name]
+[ v3_req ]
+basicConstraints = CA:FALSE
+keyUsage = nonRepudiation, digitalSignature, keyEncipherment
+extendedKeyUsage = serverAuth
+subjectAltName = @alt_names
+[alt_names]
+DNS.1 = ${service}
+DNS.2 = ${service}.${namespace}
+DNS.3 = ${service}.${namespace}.svc
+DNS.4 = ${serverIp}
+EOF
+
+outKeyFile=${destdir}/server-key.pem
+outCertFile=${destdir}/server.crt
+
+openssl genrsa -out ${outKeyFile} 2048 || exit 2
+if [ ! -z "${service}" ]; then
+  subjectCN="${service}.${namespace}.svc"
+  echo "Configuring work WITHIN a cluster with CN=${subjectCN}"
+else
+  subjectCN=${serverIp}
+  echo "Configuring work OUTSIDE a cluster with CN=${subjectCN}"
+fi
+
+openssl req -new -key ${destdir}/server-key.pem -subj "/CN=${subjectCN}" -out ${tmpdir}/server.csr -config ${tmpdir}/csr.conf || exit 3
+
+CSR_NAME=${service}.cert-request
+kubectl delete csr ${CSR_NAME} 2>/dev/null
+
+cat <<EOF | kubectl create -f -
+apiVersion: certificates.k8s.io/v1beta1
+kind: CertificateSigningRequest
+metadata:
+  name: ${CSR_NAME}
+spec:
+  groups:
+  - system:authenticated
+  request: $(cat ${tmpdir}/server.csr | base64 | tr -d '\n')
+  usages:
+  - digital signature
+  - key encipherment
+  - server auth
+EOF
+
+kubectl certificate approve ${CSR_NAME} || exit 4
+kubectl get csr ${CSR_NAME} -o jsonpath='{.status.certificate}' | base64 --decode > ${outCertFile} || exit 5
+
+echo "Generated:"
+echo ${outKeyFile}
+echo ${outCertFile}

scripts/test-web-hook.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+# You should see the trace of requests in the output of webhook server
+kubectl create configmap test-config-map --from-literal="some_var=some_value"
+kubectl delete configmap test-config-map

server/server.go

@@ -0,0 +1,76 @@
+package server
+
+import (
+	"net/http/httputil"
+	"net/http"
+	"crypto/tls"
+	"context"
+	"time"
+	"log"
+	"os"
+)
+
+// WebhookServer is a struct that describes 
+// TLS server with mutation webhook
+type WebhookServer struct {
+	server http.Server
+	logger *log.Logger
+}
+
+func (ws *WebhookServer) serve(w http.ResponseWriter, r *http.Request) {
+	dump, _ := httputil.DumpRequest(r, true)
+	ws.logger.Printf("%s", dump)
+}
+
+// RunAsync runs TLS server in separate 
+// thread and returns control immediately
+func (ws *WebhookServer) RunAsync() {
+	go func(ws *WebhookServer) {
+		err := ws.server.ListenAndServeTLS("", "")
+		if err != nil {
+			ws.logger.Fatal(err)
+		}
+	}(ws)
+}
+
+// Stop stops TLS server
+func (ws *WebhookServer) Stop() {
+	err := ws.server.Shutdown(context.Background())
+	if err != nil {
+		// Error from closing listeners, or context timeout:
+		ws.logger.Printf("Server Shutdown error: %v", err)
+		ws.server.Close()
+	}
+}
+
+// NewWebhookServer creates new instance of WebhookServer and configures it
+func NewWebhookServer(certFile string, keyFile string, logger *log.Logger) *WebhookServer {
+	if logger == nil {
+		logger = log.New(os.Stdout, "", log.LstdFlags|log.Lshortfile)
+	}
+	
+	var config tls.Config
+	pair, err := tls.LoadX509KeyPair(certFile, keyFile)
+	if err != nil {
+		logger.Fatal("Unable to load certificate and key: ", err)
+	}
+	config.Certificates = []tls.Certificate{pair}
+
+	mux := http.NewServeMux()
+	
+    ws := &WebhookServer {
+		server: http.Server {
+			Addr:         ":443", // Listen on port for HTTPS requests
+			TLSConfig:    &config,
+			Handler:      mux,
+			ErrorLog:     logger,
+			ReadTimeout:  5 * time.Second,
+			WriteTimeout: 5 * time.Second,
+		},
+		logger: logger,
+	}
+
+	mux.HandleFunc("/mutate", ws.serve)
+
+	return ws
+}