kubernetes · rfranzke · Apr 9, 2020
diff --git a/cmd/cinder-csi-plugin/main.go b/cmd/cinder-csi-plugin/main.go
@@ -21,20 +21,23 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/spf13/cobra"
-	"github.com/spf13/pflag"
 	"k8s.io/cloud-provider-openstack/pkg/csi/cinder"
 	"k8s.io/cloud-provider-openstack/pkg/csi/cinder/openstack"
 	"k8s.io/cloud-provider-openstack/pkg/util/mount"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
 	"k8s.io/component-base/logs"
 	"k8s.io/klog"
 )
 
 var (
-	endpoint    string
-	nodeID      string
-	cloudconfig string
-	cluster     string
+	cloudconfig          string
+	cluster              string
+	endpoint             string
+	nodeID               string
+	runControllerService bool
+	runNodeService       bool
 )
 
 func init() {
@@ -73,16 +76,20 @@ func main() {
 
 	cmd.Flags().AddGoFlagSet(flag.CommandLine)
 
-	cmd.PersistentFlags().StringVar(&nodeID, "nodeid", "", "node id")
-	cmd.MarkPersistentFlagRequired("nodeid")
+	cmd.PersistentFlags().StringVar(&cloudconfig, "cloud-config", "", "CSI driver cloud config")
+	cmd.MarkPersistentFlagRequired("cloud-config")
+
+	cmd.PersistentFlags().StringVar(&cluster, "cluster", "", "The identifier of the cluster that the plugin is running in.")
 
 	cmd.PersistentFlags().StringVar(&endpoint, "endpoint", "", "CSI endpoint")
 	cmd.MarkPersistentFlagRequired("endpoint")
 
-	cmd.PersistentFlags().StringVar(&cloudconfig, "cloud-config", "", "CSI driver cloud config")
-	cmd.MarkPersistentFlagRequired("cloud-config")
+	cmd.PersistentFlags().StringVar(&nodeID, "nodeid", "", "node id")
+	cmd.MarkPersistentFlagRequired("nodeid")
 
-	cmd.PersistentFlags().StringVar(&cluster, "cluster", "", "The identifier of the cluster that the plugin is running in.")
+	cmd.PersistentFlags().BoolVar(&runControllerService, "run-controller-service", true, "If set to false then the CSI driver does not activate its controller service (default: true)")
+
+	cmd.PersistentFlags().BoolVar(&runNodeService, "run-node-service", true, "If set to false then the CSI driver does not activate its node service (default: true)")
 
 	openstack.AddExtraFlags(pflag.CommandLine)
 
@@ -98,30 +105,43 @@ func main() {
 }
 
 func handle() {
-
 	d := cinder.NewDriver(nodeID, endpoint, cluster)
 
-	//Intiliaze mount
-	mount, err := mount.GetMountProvider()
+	// Initialize cloud
+	openstack.InitOpenStackProvider(cloudconfig)
+	cloud, err := openstack.GetOpenStackProvider()
 	if err != nil {
-		klog.V(3).Infof("Failed to GetMountProvider: %v", err)
+		klog.Warningf("Failed to GetOpenStackProvider: %v", err)
+		return
 	}
 
-	//Intiliaze Metadatda
-	metadatda, err := openstack.GetMetadataProvider()
-	if err != nil {
-		klog.V(3).Infof("Failed to GetMetadataProvider: %v", err)
+	// Initialize driver services
+	var (
+		ids = cinder.NewIdentityServer(d)
+		cs  *cinder.ControllerServer
+		ns  *cinder.NodeServer
+	)
+
+	if runControllerService {
+		cs = cinder.NewControllerServer(d, cloud)
 	}
 
-	// Initiliaze cloud
-	openstack.InitOpenStackProvider(cloudconfig)
-	cloud, err := openstack.GetOpenStackProvider()
+	if runNodeService {
+		// Initialize mount
+		mount, err := mount.GetMountProvider()
+		if err != nil {
+			klog.V(3).Infof("Failed to GetMountProvider: %v", err)
+		}
 
-	if err != nil {
-		klog.Warningf("Failed to GetOpenStackProvider: %v", err)
-		return
+		// Initialize Metadatda
+		metadata, err := openstack.GetMetadataProvider()
+		if err != nil {
+			klog.V(3).Infof("Failed to GetMetadataProvider: %v", err)
+		}
+
+		ns = cinder.NewNodeServer(d, mount, metadata, cloud)
 	}
 
-	d.SetupDriver(cloud, mount, metadatda)
+	d.SetupDriver(ids, cs, ns)
 	d.Run()
 }
diff --git a/docs/using-cinder-csi-plugin.md b/docs/using-cinder-csi-plugin.md
@@ -560,3 +560,16 @@ CSIVolumeID
 $ csc node get-id --endpoint tcp://127.0.0.1:10000
 CSINodeID
 ```
+
+### Disabling particular driver services
+
+Traditionally, you run the CSI controllers with the OpenStack Cinder driver in the same Kubernetes cluster.
+Though, there may be cases where you will only want to run a subset of the available driver services (for example, one scenario is running the controllers outside of the cluster they are serving (while the OpenStack Cinder driver still runs inside the served cluster), but there might be others scenarios).
+The CSI driver consists out of these services:
+
+* The **controller** service starts the GRPC server that serves `CreateVolume`, `DeleteVolume`, etc. It is depending on the OpenStack cloud config + credentials and talks with the OpenStack API.
+* The **identity** service is responsible to provide identity services like capability information of the CSI plugin.
+* The **node** service implements the various operations for volumes that are run locally from the node, for example `NodePublishVolume`, `NodeStageVolume`, etc. It does not do operations like `CreateVolume` or `ControllerPublish`. Also, it runs directly on the OpenStack VM instances. It is also depending on the OpenStack cloud config + credentials.
+
+The CSI driver has two command line flags, `--run-controller-service` and `--run-node-service` which both default to `true`.
+You can disable the individual services by setting the respective flags to `false`.
diff --git a/pkg/csi/cinder/controllerserver.go b/pkg/csi/cinder/controllerserver.go
@@ -35,12 +35,12 @@ import (
 	"k8s.io/klog"
 )
 
-type controllerServer struct {
+type ControllerServer struct {
 	Driver *CinderDriver
 	Cloud  openstack.IOpenStack
 }
 
-func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVolumeRequest) (*csi.CreateVolumeResponse, error) {
+func (cs *ControllerServer) CreateVolume(ctx context.Context, req *csi.CreateVolumeRequest) (*csi.CreateVolumeResponse, error) {
 
 	// Volume Name
 	volName := req.GetName()
@@ -120,7 +120,7 @@ func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVol
 	return getCreateVolumeResponse(vol), nil
 }
 
-func (cs *controllerServer) DeleteVolume(ctx context.Context, req *csi.DeleteVolumeRequest) (*csi.DeleteVolumeResponse, error) {
+func (cs *ControllerServer) DeleteVolume(ctx context.Context, req *csi.DeleteVolumeRequest) (*csi.DeleteVolumeResponse, error) {
 
 	// Volume Delete
 	volID := req.GetVolumeId()
@@ -142,7 +142,7 @@ func (cs *controllerServer) DeleteVolume(ctx context.Context, req *csi.DeleteVol
 	return &csi.DeleteVolumeResponse{}, nil
 }
 
-func (cs *controllerServer) ControllerPublishVolume(ctx context.Context, req *csi.ControllerPublishVolumeRequest) (*csi.ControllerPublishVolumeResponse, error) {
+func (cs *ControllerServer) ControllerPublishVolume(ctx context.Context, req *csi.ControllerPublishVolumeRequest) (*csi.ControllerPublishVolumeResponse, error) {
 
 	// Volume Attach
 	instanceID := req.GetNodeId()
@@ -202,7 +202,7 @@ func (cs *controllerServer) ControllerPublishVolume(ctx context.Context, req *cs
 	}, nil
 }
 
-func (cs *controllerServer) ControllerUnpublishVolume(ctx context.Context, req *csi.ControllerUnpublishVolumeRequest) (*csi.ControllerUnpublishVolumeResponse, error) {
+func (cs *ControllerServer) ControllerUnpublishVolume(ctx context.Context, req *csi.ControllerUnpublishVolumeRequest) (*csi.ControllerUnpublishVolumeResponse, error) {
 
 	// Volume Detach
 	instanceID := req.GetNodeId()
@@ -245,7 +245,7 @@ func (cs *controllerServer) ControllerUnpublishVolume(ctx context.Context, req *
 	return &csi.ControllerUnpublishVolumeResponse{}, nil
 }
 
-func (cs *controllerServer) ListVolumes(ctx context.Context, req *csi.ListVolumesRequest) (*csi.ListVolumesResponse, error) {
+func (cs *ControllerServer) ListVolumes(ctx context.Context, req *csi.ListVolumesRequest) (*csi.ListVolumesResponse, error) {
 
 	vlist, err := cs.Cloud.ListVolumes()
 	if err != nil {
@@ -268,7 +268,7 @@ func (cs *controllerServer) ListVolumes(ctx context.Context, req *csi.ListVolume
 	}, nil
 }
 
-func (cs *controllerServer) CreateSnapshot(ctx context.Context, req *csi.CreateSnapshotRequest) (*csi.CreateSnapshotResponse, error) {
+func (cs *ControllerServer) CreateSnapshot(ctx context.Context, req *csi.CreateSnapshotRequest) (*csi.CreateSnapshotResponse, error) {
 	name := req.Name
 	volumeId := req.SourceVolumeId
 
@@ -333,7 +333,7 @@ func (cs *controllerServer) CreateSnapshot(ctx context.Context, req *csi.CreateS
 	}, nil
 }
 
-func (cs *controllerServer) DeleteSnapshot(ctx context.Context, req *csi.DeleteSnapshotRequest) (*csi.DeleteSnapshotResponse, error) {
+func (cs *ControllerServer) DeleteSnapshot(ctx context.Context, req *csi.DeleteSnapshotRequest) (*csi.DeleteSnapshotResponse, error) {
 
 	id := req.SnapshotId
 
@@ -354,7 +354,7 @@ func (cs *controllerServer) DeleteSnapshot(ctx context.Context, req *csi.DeleteS
 	return &csi.DeleteSnapshotResponse{}, nil
 }
 
-func (cs *controllerServer) ListSnapshots(ctx context.Context, req *csi.ListSnapshotsRequest) (*csi.ListSnapshotsResponse, error) {
+func (cs *ControllerServer) ListSnapshots(ctx context.Context, req *csi.ListSnapshotsRequest) (*csi.ListSnapshotsResponse, error) {
 
 	if len(req.GetSnapshotId()) != 0 {
 		snap, err := cs.Cloud.GetSnapshotByID(req.SnapshotId)
@@ -429,15 +429,15 @@ func (cs *controllerServer) ListSnapshots(ctx context.Context, req *csi.ListSnap
 
 // ControllerGetCapabilities implements the default GRPC callout.
 // Default supports all capabilities
-func (cs *controllerServer) ControllerGetCapabilities(ctx context.Context, req *csi.ControllerGetCapabilitiesRequest) (*csi.ControllerGetCapabilitiesResponse, error) {
+func (cs *ControllerServer) ControllerGetCapabilities(ctx context.Context, req *csi.ControllerGetCapabilitiesRequest) (*csi.ControllerGetCapabilitiesResponse, error) {
 	klog.V(5).Infof("Using default ControllerGetCapabilities")
 
 	return &csi.ControllerGetCapabilitiesResponse{
 		Capabilities: cs.Driver.cscap,
 	}, nil
 }
 
-func (cs *controllerServer) ValidateVolumeCapabilities(ctx context.Context, req *csi.ValidateVolumeCapabilitiesRequest) (*csi.ValidateVolumeCapabilitiesResponse, error) {
+func (cs *ControllerServer) ValidateVolumeCapabilities(ctx context.Context, req *csi.ValidateVolumeCapabilitiesRequest) (*csi.ValidateVolumeCapabilitiesResponse, error) {
 
 	reqVolCap := req.GetVolumeCapabilities()
 
@@ -478,11 +478,11 @@ func (cs *controllerServer) ValidateVolumeCapabilities(ctx context.Context, req
 	return resp, nil
 }
 
-func (cs *controllerServer) GetCapacity(ctx context.Context, req *csi.GetCapacityRequest) (*csi.GetCapacityResponse, error) {
+func (cs *ControllerServer) GetCapacity(ctx context.Context, req *csi.GetCapacityRequest) (*csi.GetCapacityResponse, error) {
 	return nil, status.Error(codes.Unimplemented, fmt.Sprintf("GetCapacity is not yet implemented"))
 }
 
-func (cs *controllerServer) ControllerExpandVolume(ctx context.Context, req *csi.ControllerExpandVolumeRequest) (*csi.ControllerExpandVolumeResponse, error) {
+func (cs *ControllerServer) ControllerExpandVolume(ctx context.Context, req *csi.ControllerExpandVolumeRequest) (*csi.ControllerExpandVolumeResponse, error) {
 	klog.V(4).Infof("ControllerExpandVolume: called with args %+v", *req)
 
 	volumeID := req.GetVolumeId()

diff --git a/pkg/csi/cinder/controllerserver_test.go b/pkg/csi/cinder/controllerserver_test.go
@@ -25,7 +25,7 @@ import (
 	"k8s.io/cloud-provider-openstack/pkg/csi/cinder/openstack"
 )
 
-var fakeCs *controllerServer
+var fakeCs *ControllerServer
 var osmock *openstack.OpenStackMock
 
 // Init Controller Server

diff --git a/pkg/csi/cinder/driver.go b/pkg/csi/cinder/driver.go
@@ -22,8 +22,6 @@ import (
 	"github.com/container-storage-interface/spec/lib/go/csi"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
-	"k8s.io/cloud-provider-openstack/pkg/csi/cinder/openstack"
-	"k8s.io/cloud-provider-openstack/pkg/util/mount"
 	"k8s.io/klog"
 )
 
@@ -44,9 +42,9 @@ type CinderDriver struct {
 	cloudconfig string
 	cluster     string
 
-	ids *identityServer
-	cs  *controllerServer
-	ns  *nodeServer
+	ids *IdentityServer
+	cs  *ControllerServer
+	ns  *NodeServer
 
 	vcap  []*csi.VolumeCapability_AccessMode
 	cscap []*csi.ControllerServiceCapability
@@ -135,15 +133,12 @@ func (d *CinderDriver) GetVolumeCapabilityAccessModes() []*csi.VolumeCapability_
 	return d.vcap
 }
 
-func (d *CinderDriver) SetupDriver(cloud openstack.IOpenStack, mount mount.IMount, metadata openstack.IMetadata) {
-
-	d.ids = NewIdentityServer(d)
-	d.cs = NewControllerServer(d, cloud)
-	d.ns = NewNodeServer(d, mount, metadata, cloud)
-
+func (d *CinderDriver) SetupDriver(ids *IdentityServer, cs *ControllerServer, ns *NodeServer) {
+	d.ids = ids
+	d.cs = cs
+	d.ns = ns
 }
 
 func (d *CinderDriver) Run() {
-
-	RunControllerandNodePublishServer(d.endpoint, d.ids, d.cs, d.ns)
+	RunControllerAndNodePublishServer(d.endpoint, d.ids, d.cs, d.ns)
 }
diff --git a/pkg/csi/cinder/identityserver.go b/pkg/csi/cinder/identityserver.go
@@ -25,11 +25,11 @@ import (
 	"k8s.io/klog"
 )
 
-type identityServer struct {
+type IdentityServer struct {
 	Driver *CinderDriver
 }
 
-func (ids *identityServer) GetPluginInfo(ctx context.Context, req *csi.GetPluginInfoRequest) (*csi.GetPluginInfoResponse, error) {
+func (ids *IdentityServer) GetPluginInfo(ctx context.Context, req *csi.GetPluginInfoRequest) (*csi.GetPluginInfoResponse, error) {
 	klog.V(5).Infof("Using default GetPluginInfo")
 
 	if ids.Driver.name == "" {
@@ -46,7 +46,7 @@ func (ids *identityServer) GetPluginInfo(ctx context.Context, req *csi.GetPlugin
 	}, nil
 }
 
-func (ids *identityServer) Probe(ctx context.Context, req *csi.ProbeRequest) (*csi.ProbeResponse, error) {
+func (ids *IdentityServer) Probe(ctx context.Context, req *csi.ProbeRequest) (*csi.ProbeResponse, error) {
 	klog.V(5).Infof("Probe() called with req %+v", req)
 	oProvider, err := openstack.GetOpenStackProvider()
 	if err != nil {
@@ -60,7 +60,7 @@ func (ids *identityServer) Probe(ctx context.Context, req *csi.ProbeRequest) (*c
 	return &csi.ProbeResponse{}, nil
 }
 
-func (ids *identityServer) GetPluginCapabilities(ctx context.Context, req *csi.GetPluginCapabilitiesRequest) (*csi.GetPluginCapabilitiesResponse, error) {
+func (ids *IdentityServer) GetPluginCapabilities(ctx context.Context, req *csi.GetPluginCapabilitiesRequest) (*csi.GetPluginCapabilitiesResponse, error) {
 	klog.V(5).Infof("GetPluginCapabilities called with req %+v", req)
 	return &csi.GetPluginCapabilitiesResponse{
 		Capabilities: []*csi.PluginCapability{