From 79cb9694d0ff5ef97966dc24911d107177c23adf Mon Sep 17 00:00:00 2001
From: Rafael Franzke <rafael.franzke@sap.com>
Date: Fri, 10 Jan 2020 10:21:15 +0100
Subject: [PATCH] Allow running the controller service separately

---
 Dockerfile               |  2 +-
 cmd/main.go              | 10 ++++++++--
 go.sum                   |  1 +
 pkg/driver/controller.go | 12 ++++++++----
 pkg/driver/driver.go     | 22 ++++++++++++++++++++--
 5 files changed, 38 insertions(+), 9 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index 44e739229a..6d4e40d255 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -15,7 +15,7 @@
 FROM golang:1.12.7-stretch as builder
 WORKDIR /go/src/github.com/kubernetes-sigs/aws-ebs-csi-driver
 ADD . .
-RUN make 
+RUN make
 
 FROM amazonlinux:2
 RUN yum install ca-certificates e2fsprogs xfsprogs util-linux -y
diff --git a/cmd/main.go b/cmd/main.go
index e2e096a465..e5b5ba6b21 100644
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -28,14 +28,18 @@ import (
 
 func main() {
 	var (
-		version         bool
 		endpoint        string
 		extraVolumeTags map[string]string
+		region          string
+		runAsController bool
+		version         bool
 	)
 
-	flag.BoolVar(&version, "version", false, "Print the version and exit.")
 	flag.StringVar(&endpoint, "endpoint", driver.DefaultCSIEndpoint, "CSI Endpoint")
 	flag.Var(cliflag.NewMapStringString(&extraVolumeTags), "extra-volume-tags", "Extra volume tags to attach to each dynamically provisioned volume. It is a comma separated list of key value pairs like '<key1>=<value1>,<key2>=<value2>'")
+	flag.StringVar(&region, "region", "", "If specified then the given AWS region will be taken instead of trying to look it up via the AWS EC2 metadata service.")
+	flag.BoolVar(&runAsController, "run-as-controller", false, "If set to true then the CSI driver runs the controller only and does not start the node service.")
+	flag.BoolVar(&version, "version", false, "Print the version and exit.")
 
 	klog.InitFlags(nil)
 	flag.Parse()
@@ -52,6 +56,8 @@ func main() {
 	drv, err := driver.NewDriver(
 		driver.WithEndpoint(endpoint),
 		driver.WithExtraVolumeTags(extraVolumeTags),
+		driver.WithRegion(region),
+		driver.WithRunAsController(runAsController),
 	)
 	if err != nil {
 		klog.Fatalln(err)
diff --git a/go.sum b/go.sum
index ffa9f1fee0..88e97fc109 100644
--- a/go.sum
+++ b/go.sum
@@ -48,6 +48,7 @@ github.com/codedellemc/goscaleio v0.0.0-20170830184815-20e2ce2cf885/go.mod h1:JI
 github.com/codegangsta/negroni v1.0.0/go.mod h1:v0y3T5G7Y1UlFfyxFn/QLRU4a2EuNau2iZY63YTKWo0=
 github.com/container-storage-interface/spec v1.1.0 h1:qPsTqtR1VUPvMPeK0UnCZMtXaKGyyLPG8gj/wG6VqMs=
 github.com/container-storage-interface/spec v1.1.0/go.mod h1:6URME8mwIBbpVyZV93Ce5St17xBiQJQY67NDsuohiy4=
+github.com/container-storage-interface/spec v1.2.0 h1:bD9KIVgaVKKkQ/UbVUY9kCaH/CJbhNxe0eeB4JeJV2s=
 github.com/containerd/console v0.0.0-20170925154832-84eeaae905fa/go.mod h1:Tj/on1eG8kiEhd0+fhSDzsPAFESxzBBvdyEgyryXffw=
 github.com/containerd/containerd v1.0.2/go.mod h1:bC6axHOhabU15QhwfG7w5PipXdVtMXFTttgp+kVtyUA=
 github.com/containerd/typeurl v0.0.0-20190228175220-2a93cfde8c20/go.mod h1:Cm3kwCdlkCfMSHURc+r6fwoGH6/F1hH3S4sg0rLFWPc=
diff --git a/pkg/driver/controller.go b/pkg/driver/controller.go
index 3de13be2c7..ed87d7e48f 100644
--- a/pkg/driver/controller.go
+++ b/pkg/driver/controller.go
@@ -59,11 +59,15 @@ type controllerService struct {
 // newControllerService creates a new controller service
 // it panics if failed to create the service
 func newControllerService(driverOptions *DriverOptions) controllerService {
-	metadata, err := cloud.NewMetadata()
-	if err != nil {
-		panic(err)
+	region := driverOptions.region
+	if region == "" {
+		metadata, err := cloud.NewMetadata()
+		if err != nil {
+			panic(err)
+		}
+		region = metadata.GetRegion()
 	}
-	region := metadata.GetRegion()
+
 	cloud, err := cloud.NewCloud(region)
 	if err != nil {
 		panic(err)
diff --git a/pkg/driver/driver.go b/pkg/driver/driver.go
index 0367f3069b..e983c73f60 100644
--- a/pkg/driver/driver.go
+++ b/pkg/driver/driver.go
@@ -43,13 +43,16 @@ type Driver struct {
 type DriverOptions struct {
 	endpoint        string
 	extraVolumeTags map[string]string
+	region          string
+	runAsController bool
 }
 
 func NewDriver(options ...func(*DriverOptions)) (*Driver, error) {
 	klog.Infof("Driver: %v Version: %v", DriverName, driverVersion)
 
 	driverOptions := DriverOptions{
-		endpoint: DefaultCSIEndpoint,
+		endpoint:        DefaultCSIEndpoint,
+		runAsController: false,
 	}
 	for _, option := range options {
 		option(&driverOptions)
@@ -61,10 +64,13 @@ func NewDriver(options ...func(*DriverOptions)) (*Driver, error) {
 
 	driver := Driver{
 		controllerService: newControllerService(&driverOptions),
-		nodeService:       newNodeService(),
 		options:           &driverOptions,
 	}
 
+	if driverOptions.runAsController {
+		driver.nodeService = newNodeService()
+	}
+
 	return &driver, nil
 }
 
@@ -110,6 +116,18 @@ func WithEndpoint(endpoint string) func(*DriverOptions) {
 	}
 }
 
+func WithRegion(region string) func(*DriverOptions) {
+	return func(o *DriverOptions) {
+		o.region = region
+	}
+}
+
+func WithRunAsController(runAsController bool) func(*DriverOptions) {
+	return func(o *DriverOptions) {
+		o.runAsController = runAsController
+	}
+}
+
 func WithExtraVolumeTags(extraVolumeTags map[string]string) func(*DriverOptions) {
 	return func(o *DriverOptions) {
 		o.extraVolumeTags = extraVolumeTags