More refactoring. Framework for external driver client. Unit tests.

hack/fakegrpcserver/fakegrpcserver.go

@@ -1,9 +1,60 @@
 package main
 
 import (
+	"log"
+	"path"
+	"time"
+
 	svr "github.com/gardener/machine-controller-manager/pkg/grpc/infraserver"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/testdata"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+var (
+	tls      = false //"Connection uses TLS if true, else plain TCP"
+	certFile = ""    //"The TLS cert file"
+	keyFile  = ""    //"The TLS key file"
+	port     = 10000 //"The server port"
 )
 
 func main() {
-	svr.StartServer()
+	server := &svr.ExternalDriverManager{
+		Port:   port,
+		UseTLS: tls,
+	}
+	if tls {
+		if certFile == "" {
+			certFile = testdata.Path("server1.pem")
+		}
+		if keyFile == "" {
+			keyFile = testdata.Path("server1.key")
+		}
+		creds, err := credentials.NewServerTLSFromFile(certFile, keyFile)
+		if err != nil {
+			log.Fatalf("Failed to generate credentials %v", err)
+		}
+		server.Options = []grpc.ServerOption{grpc.Creds(creds)}
+	}
+
+	server.Start()
+
+	// Test go routine to test end to end flow
+	go func() {
+		for {
+			driver, _ := server.GetDriver(metav1.TypeMeta{
+				Kind:       "driver",
+				APIVersion: path.Join("poc", "alpha"),
+			})
+
+			time.Sleep(5 * time.Second)
+			log.Printf("Calling create")
+			driver.Create("fakeDriver", "a", "b")
+
+			time.Sleep(5 * time.Second)
+			log.Printf("Calling delete")
+			driver.Delete("fakeDriver", "a", "b")
+		}
+	}()
 }

pkg/grpc/infraclient/infraclient.go

@@ -0,0 +1,184 @@
+/*
+Copyright (c) 2017 SAP SE or an SAP affiliate company. All rights reserved.
+
+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 infraclient
+
+import (
+	"context"
+	"io"
+
+	pb "github.com/gardener/machine-controller-manager/pkg/grpc/infrapb"
+	"github.com/golang/glog"
+	"google.golang.org/grpc"
+)
+
+// ExternalDriver structure mediates the communication with the machine-controller-manager
+type ExternalDriver struct {
+	serverAddr string
+	options    []grpc.DialOption
+	provider   ExternalDriverProvider
+	connection *grpc.ClientConn
+	stream     pb.Infragrpc_RegisterClient
+}
+
+// NewExternalDriver creates a new Driver instance.
+func NewExternalDriver(serverAddr string, options []grpc.DialOption, provider ExternalDriverProvider) *ExternalDriver {
+	return &ExternalDriver{
+		serverAddr: serverAddr,
+		options:    options,
+		provider:   provider,
+	}
+}
+
+// Start starts the external driver.
+func (d *ExternalDriver) Start() error {
+	conn, err := grpc.Dial(d.serverAddr, d.options...)
+	if err != nil {
+		glog.Fatalf("fail to dial: %v", err)
+		return err
+	}
+	d.connection = conn
+	client := pb.NewInfragrpcClient(conn)
+
+	go func() {
+		d.serveMCM(client)
+	}()
+
+	return nil
+}
+
+// Stop stops the external driver.
+func (d *ExternalDriver) Stop() error {
+	stream := d.stream
+	//connection := d.connection
+
+	d.stream = nil
+	d.connection = nil
+
+	if stream != nil && stream.Context().Err() == nil {
+		stream.Send(&pb.DriverSide{
+			OperationType: "unregister",
+		})
+		stream.CloseSend()
+	}
+	var err error
+	/*
+		if connection != nil {
+			err = connection.Close()
+		}
+	*/
+
+	return err
+}
+
+func (d *ExternalDriver) serveMCM(client pb.InfragrpcClient) error {
+	glog.Infof("Registering with MCM...")
+	ctx := context.Background()
+
+	stream, err := client.Register(ctx)
+	if err != nil {
+		glog.Fatalf("%v.Register(_) = _, %v: ", client, err)
+		return err
+	}
+
+	d.stream = stream
+
+	for {
+		in, err := stream.Recv()
+		if err == io.EOF {
+			// read done.
+			return err
+		}
+		if err != nil {
+			glog.Fatalf("Failed to receive: %v", err)
+			return err
+		}
+
+		glog.Infof("Operation %s", in.OperationType)
+		opParams := in.GetOperationparams()
+		glog.Infof("create parameters: %v", opParams)
+
+		resp := pb.DriverSide{}
+		resp.OperationID = in.OperationID
+		resp.OperationType = in.OperationType
+
+		switch in.OperationType {
+		case "register":
+			machineClassType := d.provider.Register()
+			pMachineClassType := &machineClassType
+			gvk := pMachineClassType.GroupVersionKind()
+			resp.Response = &pb.DriverSide_RegisterResp{
+				RegisterResp: &pb.DriverSideRegisterationResp{
+					Name:    "externalDriver",
+					Kind:    gvk.Kind,
+					Group:   gvk.Group,
+					Version: gvk.Version,
+				},
+			}
+		case "create":
+			var machineClass *MachineClassMeta
+			if opParams.MachineClassMetaData != nil {
+				machineClass = &MachineClassMeta{
+					Name:     opParams.MachineClassMetaData.Name,
+					Revision: opParams.MachineClassMetaData.Revision,
+				}
+			}
+			providerID, nodename, err := d.provider.Create(machineClass, opParams.Credentials, opParams.MachineID, opParams.MachineName)
+
+			var sErr string
+			if err != nil {
+				sErr = err.Error()
+			}
+			resp.Response = &pb.DriverSide_Createresponse{
+				Createresponse: &pb.DriverSideCreateResp{
+					ProviderID: providerID,
+					Nodename:   nodename,
+					Error:      sErr,
+				},
+			}
+		case "delete":
+			err := d.provider.Delete(opParams.Credentials, opParams.MachineID)
+			var sErr string
+			if err != nil {
+				sErr = err.Error()
+			}
+			resp.Response = &pb.DriverSide_Deleteresponse{
+				Deleteresponse: &pb.DriverSideDeleteResp{
+					Error: sErr,
+				},
+			}
+		case "list":
+			vms, err := d.provider.List(opParams.MachineID)
+			list := []string{}
+
+			var sErr string
+			if err == nil {
+				for _, machineID := range vms {
+					list = append(list, machineID)
+				}
+			} else {
+				sErr = err.Error()
+			}
+			resp.Response = &pb.DriverSide_Listresponse{
+				Listresponse: &pb.DriverSideListResp{
+					List:  list,
+					Error: sErr,
+				},
+			}
+		}
+
+		stream.Send(&resp)
+	}
+}

pkg/grpc/infraclient/provider.go

@@ -0,0 +1,34 @@
+/*
+Copyright (c) 2017 SAP SE or an SAP affiliate company. All rights reserved.
+
+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 infraclient
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// MachineClassMeta has metadata about the machine class.
+type MachineClassMeta struct {
+	Name     string
+	Revision int32
+}
+
+// ExternalDriverProvider interface must be implemented by the providers.
+type ExternalDriverProvider interface {
+	Register() metav1.TypeMeta
+	Create(machineclass *MachineClassMeta, credentials, machineID, machineName string) (string, string, error)
+	Delete(credentials, machineID string) error
+	List(machineID string) (map[string]string, error)
+}