Add --rudder-address flag to tiller server

Before this change it was possible to use only local rudder. As a consequence
it was required to change tiller-deploy definition generated by helm init.

This change adds --rudder-address flag to tiller server, by default it will be
set to 127.0.0.1:10001. Rudder address wil be ignore if --experimental-release
won't be added. Also tiller will crash if rudder server is provided without experimental release.
In my opinion this is a sane way to preserve previous behaviour.

I included refactoring of rudder grpc client as it is safe to reuse same connection
with multiple concurrent users and it is nice cleanup.

cmd/rudder/rudder.go

@@ -29,6 +29,7 @@ import (
 	"github.com/spf13/pflag"
 	"k8s.io/helm/pkg/kube"
 	rudderAPI "k8s.io/helm/pkg/proto/hapi/rudder"
+	"k8s.io/helm/pkg/rudder"
 	"k8s.io/helm/pkg/tiller"
 	"k8s.io/helm/pkg/version"
 )
@@ -41,8 +42,8 @@ type options struct {
 }
 
 func (opts *options) registerFlags() {
-	pflag.StringVarP(&opts.listen, "listen", "l", "127.0.0.1:10001",
-		"Socket for rudder grpc server (default: 127.0.0.1:10001).")
+	pflag.StringVarP(&opts.listen, "listen", "l", rudder.RudderDefaultAddress,
+		fmt.Sprintf("Socket for rudder grpc server (default: %s).", rudder.RudderDefaultAddress))
 }
 
 func (opts *options) parseFlags() {

cmd/tiller/tiller.go

@@ -35,6 +35,7 @@ import (
 
 	"k8s.io/helm/pkg/kube"
 	"k8s.io/helm/pkg/proto/hapi/services"
+	"k8s.io/helm/pkg/rudder"
 	"k8s.io/helm/pkg/storage"
 	"k8s.io/helm/pkg/storage/driver"
 	"k8s.io/helm/pkg/tiller"
@@ -70,6 +71,9 @@ var (
 	enableTracing        = flag.Bool("trace", false, "enable rpc tracing")
 	store                = flag.String("storage", storageConfigMap, "storage driver to use. One of 'configmap' or 'memory'")
 	remoteReleaseModules = flag.Bool("experimental-release", false, "enable experimental release modules")
+	rudderAddress        = flag.String("rudder-address", rudder.RudderDefaultAddress,
+		fmt.Sprintf("rudder address:port (default: %s). ignored if experimental-release is omitted",
+			rudder.RudderDefaultAddress))
 	tlsEnable  = flag.Bool("tls", tlsEnableEnvVarDefault(), "enable TLS")
 	tlsVerify  = flag.Bool("tls-verify", tlsVerifyEnvVarDefault(), "enable TLS and verify remote certificate")
 	keyFile    = flag.String("tls-key", tlsDefaultsFromEnv("tls-key"), "path to TLS private key file")
@@ -102,6 +106,12 @@ func main() {
 }
 
 func start() {
+	if *rudderAddress != rudder.RudderDefaultAddress && !*remoteReleaseModules {
+		log.Fatal(
+			"Rudder address will be ignored without --experimental-release flag.",
+			"Add --experimental-release or remove --rudder-address.",
+		)
+	}
 
 	clientset, err := kube.New(nil).ClientSet()
 	if err != nil {
@@ -163,7 +173,15 @@ func start() {
 	srvErrCh := make(chan error)
 	probeErrCh := make(chan error)
 	go func() {
-		svc := tiller.NewReleaseServer(env, clientset, *remoteReleaseModules)
+		var addressToUse string
+		if *remoteReleaseModules {
+			addressToUse = *rudderAddress
+		}
+		svc, err := tiller.NewReleaseServer(env, clientset, addressToUse)
+		if err != nil {
+			srvErrCh <- err
+			return
+		}
 		svc.Log = newLogger("tiller").Printf
 		services.RegisterReleaseServiceServer(rootServer, svc)
 		if err := rootServer.Serve(lstn); err != nil {

pkg/rudder/client.go

@@ -18,6 +18,7 @@ package rudder // import "k8s.io/helm/pkg/rudder"
 
 import (
 	"fmt"
+	"time"
 
 	"golang.org/x/net/context"
 	"google.golang.org/grpc"
@@ -25,67 +26,51 @@ import (
 	rudderAPI "k8s.io/helm/pkg/proto/hapi/rudder"
 )
 
-// GrpcPort specifies port on which rudder will spawn a server
+// RudderDefaultAddress will be used if none is provided with command lines argumnets.
 const (
-	GrpcPort = 10001
+	RudderDefaultAddress = "127.0.0.1:10001"
 )
 
-var grpcAddr = fmt.Sprintf("127.0.0.1:%d", GrpcPort)
-
-// InstallRelease calls Rudder InstallRelease method which should create provided release
-func InstallRelease(rel *rudderAPI.InstallReleaseRequest) (*rudderAPI.InstallReleaseResponse, error) {
+// NewClient creates new instance of Client.
+func NewClient(address string) (*Client, error) {
 	//TODO(mkwiek): parametrize this
-	conn, err := grpc.Dial(grpcAddr, grpc.WithInsecure())
+	conn, err := grpc.Dial(
+		address,
+		grpc.WithInsecure(),
+		grpc.WithBlock(),
+		grpc.WithTimeout(3*time.Second))
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("error establishing connection with rudder using address %s: %v", address, err)
 	}
+	return &Client{client: rudderAPI.NewReleaseModuleServiceClient(conn)}, nil
+}
+
+// Client wraps rudder grpc client.
+type Client struct {
+	client rudderAPI.ReleaseModuleServiceClient
+}
 
-	defer conn.Close()
-	client := rudderAPI.NewReleaseModuleServiceClient(conn)
-	return client.InstallRelease(context.Background(), rel)
+// InstallRelease calls Rudder InstallRelease method which should create provided release
+func (c *Client) InstallRelease(rel *rudderAPI.InstallReleaseRequest) (*rudderAPI.InstallReleaseResponse, error) {
+	return c.client.InstallRelease(context.Background(), rel)
 }
 
 // UpgradeRelease calls Rudder UpgradeRelease method which should perform update
-func UpgradeRelease(req *rudderAPI.UpgradeReleaseRequest) (*rudderAPI.UpgradeReleaseResponse, error) {
-	conn, err := grpc.Dial(grpcAddr, grpc.WithInsecure())
-	if err != nil {
-		return nil, err
-	}
-	defer conn.Close()
-	client := rudderAPI.NewReleaseModuleServiceClient(conn)
-	return client.UpgradeRelease(context.Background(), req)
+func (c *Client) UpgradeRelease(req *rudderAPI.UpgradeReleaseRequest) (*rudderAPI.UpgradeReleaseResponse, error) {
+	return c.client.UpgradeRelease(context.Background(), req)
 }
 
 // RollbackRelease calls Rudder RollbackRelease method which should perform update
-func RollbackRelease(req *rudderAPI.RollbackReleaseRequest) (*rudderAPI.RollbackReleaseResponse, error) {
-	conn, err := grpc.Dial(grpcAddr, grpc.WithInsecure())
-	if err != nil {
-		return nil, err
-	}
-	defer conn.Close()
-	client := rudderAPI.NewReleaseModuleServiceClient(conn)
-	return client.RollbackRelease(context.Background(), req)
+func (c *Client) RollbackRelease(req *rudderAPI.RollbackReleaseRequest) (*rudderAPI.RollbackReleaseResponse, error) {
+	return c.client.RollbackRelease(context.Background(), req)
 }
 
 // ReleaseStatus calls Rudder ReleaseStatus method which should perform update
-func ReleaseStatus(req *rudderAPI.ReleaseStatusRequest) (*rudderAPI.ReleaseStatusResponse, error) {
-	conn, err := grpc.Dial(grpcAddr, grpc.WithInsecure())
-	if err != nil {
-		return nil, err
-	}
-	defer conn.Close()
-	client := rudderAPI.NewReleaseModuleServiceClient(conn)
-	return client.ReleaseStatus(context.Background(), req)
+func (c *Client) ReleaseStatus(req *rudderAPI.ReleaseStatusRequest) (*rudderAPI.ReleaseStatusResponse, error) {
+	return c.client.ReleaseStatus(context.Background(), req)
 }
 
 // DeleteRelease calls Rudder DeleteRelease method which should uninstall provided release
-func DeleteRelease(rel *rudderAPI.DeleteReleaseRequest) (*rudderAPI.DeleteReleaseResponse, error) {
-	conn, err := grpc.Dial(grpcAddr, grpc.WithInsecure())
-	if err != nil {
-		return nil, err
-	}
-
-	defer conn.Close()
-	client := rudderAPI.NewReleaseModuleServiceClient(conn)
-	return client.DeleteRelease(context.Background(), rel)
+func (c *Client) DeleteRelease(rel *rudderAPI.DeleteReleaseRequest) (*rudderAPI.DeleteReleaseResponse, error) {
+	return c.client.DeleteRelease(context.Background(), rel)
 }

pkg/tiller/release_modules.go

@@ -84,12 +84,23 @@ func (m *LocalReleaseModule) Delete(rel *release.Release, req *services.Uninstal
 }
 
 // RemoteReleaseModule is a ReleaseModule which calls Rudder service to operate on a release
-type RemoteReleaseModule struct{}
+type RemoteReleaseModule struct {
+	c *rudder.Client
+}
+
+// NewRemoteReleaseModule creates new instance of RemoteReleaseModule and returns it as ReleaseModule interface.
+func NewRemoteReleaseModule(address string) (ReleaseModule, error) {
+	client, err := rudder.NewClient(address)
+	if err != nil {
+		return nil, err
+	}
+	return &RemoteReleaseModule{c: client}, nil
+}
 
 // Create calls rudder.InstallRelease
 func (m *RemoteReleaseModule) Create(r *release.Release, req *services.InstallReleaseRequest, env *environment.Environment) error {
 	request := &rudderAPI.InstallReleaseRequest{Release: r}
-	_, err := rudder.InstallRelease(request)
+	_, err := m.c.InstallRelease(request)
 	return err
 }
 
@@ -103,7 +114,7 @@ func (m *RemoteReleaseModule) Update(current, target *release.Release, req *serv
 		Wait:     req.Wait,
 		Force:    req.Force,
 	}
-	_, err := rudder.UpgradeRelease(upgrade)
+	_, err := m.c.UpgradeRelease(upgrade)
 	return err
 }
 
@@ -116,14 +127,14 @@ func (m *RemoteReleaseModule) Rollback(current, target *release.Release, req *se
 		Timeout:  req.Timeout,
 		Wait:     req.Wait,
 	}
-	_, err := rudder.RollbackRelease(rollback)
+	_, err := m.c.RollbackRelease(rollback)
 	return err
 }
 
 // Status returns status retrieved from rudder.ReleaseStatus
 func (m *RemoteReleaseModule) Status(r *release.Release, req *services.GetReleaseStatusRequest, env *environment.Environment) (string, error) {
 	statusRequest := &rudderAPI.ReleaseStatusRequest{Release: r}
-	resp, err := rudder.ReleaseStatus(statusRequest)
+	resp, err := m.c.ReleaseStatus(statusRequest)
 	if resp == nil {
 		return "", err
 	}
@@ -133,7 +144,7 @@ func (m *RemoteReleaseModule) Status(r *release.Release, req *services.GetReleas
 // Delete calls rudder.DeleteRelease
 func (m *RemoteReleaseModule) Delete(r *release.Release, req *services.UninstallReleaseRequest, env *environment.Environment) (string, []error) {
 	deleteRequest := &rudderAPI.DeleteReleaseRequest{Release: r}
-	resp, err := rudder.DeleteRelease(deleteRequest)
+	resp, err := m.c.DeleteRelease(deleteRequest)
 
 	errs := make([]error, 0)
 	result := ""

pkg/tiller/release_server.go

@@ -86,10 +86,15 @@ type ReleaseServer struct {
 }
 
 // NewReleaseServer creates a new release server.
-func NewReleaseServer(env *environment.Environment, clientset internalclientset.Interface, useRemote bool) *ReleaseServer {
+func NewReleaseServer(env *environment.Environment, clientset internalclientset.Interface, rudderAddress string) (
+	*ReleaseServer, error) {
 	var releaseModule ReleaseModule
-	if useRemote {
-		releaseModule = &RemoteReleaseModule{}
+	var err error
+	if len(rudderAddress) != 0 {
+		releaseModule, err = NewRemoteReleaseModule(rudderAddress)
+		if err != nil {
+			return nil, err
+		}
 	} else {
 		releaseModule = &LocalReleaseModule{
 			clientset: clientset,
@@ -101,7 +106,7 @@ func NewReleaseServer(env *environment.Environment, clientset internalclientset.
 		clientset:     clientset,
 		ReleaseModule: releaseModule,
 		Log:           func(_ string, _ ...interface{}) {},
-	}
+	}, nil
 }
 
 // reuseValues copies values from the current release to a new release if the