open-nomad/client/csi_endpoint.go
2021-04-01 11:16:52 -04:00

506 lines
18 KiB
Go

package client
import (
"context"
"errors"
"fmt"
"time"
metrics "github.com/armon/go-metrics"
grpc_retry "github.com/grpc-ecosystem/go-grpc-middleware/retry"
"github.com/hashicorp/nomad/client/dynamicplugins"
"github.com/hashicorp/nomad/client/pluginmanager/csimanager"
"github.com/hashicorp/nomad/client/structs"
nstructs "github.com/hashicorp/nomad/nomad/structs"
"github.com/hashicorp/nomad/plugins/csi"
)
// CSI endpoint is used for interacting with CSI plugins on a client.
// TODO: Submit metrics with labels to allow debugging per plugin perf problems.
type CSI struct {
c *Client
}
const (
// CSIPluginRequestTimeout is the timeout that should be used when making reqs
// against CSI Plugins. It is copied from Kubernetes as an initial seed value.
// https://github.com/kubernetes/kubernetes/blob/e680ad7156f263a6d8129cc0117fda58602e50ad/pkg/volume/csi/csi_plugin.go#L52
CSIPluginRequestTimeout = 2 * time.Minute
)
var (
ErrPluginTypeError = errors.New("CSI Plugin loaded incorrectly")
)
// ControllerValidateVolume is used during volume registration to validate
// that a volume exists and that the capabilities it was registered with are
// supported by the CSI Plugin and external volume configuration.
func (c *CSI) ControllerValidateVolume(req *structs.ClientCSIControllerValidateVolumeRequest, resp *structs.ClientCSIControllerValidateVolumeResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "validate_volume"}, time.Now())
if req.VolumeID == "" {
return errors.New("CSI.ControllerValidateVolume: VolumeID is required")
}
if req.PluginID == "" {
return errors.New("CSI.ControllerValidateVolume: PluginID is required")
}
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerValidateVolume: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq, err := req.ToCSIRequest()
if err != nil {
return fmt.Errorf("CSI.ControllerValidateVolume: %v", err)
}
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ValidateVolumeCapabilities errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
err = plugin.ControllerValidateCapabilities(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if err != nil {
return fmt.Errorf("CSI.ControllerValidateVolume: %v", err)
}
return nil
}
// ControllerAttachVolume is used to attach a volume from a CSI Cluster to
// the storage node provided in the request.
//
// The controller attachment flow currently works as follows:
// 1. Validate the volume request
// 2. Call ControllerPublishVolume on the CSI Plugin to trigger a remote attachment
//
// In the future this may be expanded to request dynamic secrets for attachment.
func (c *CSI) ControllerAttachVolume(req *structs.ClientCSIControllerAttachVolumeRequest, resp *structs.ClientCSIControllerAttachVolumeResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "publish_volume"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerAttachVolume: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
// The following block of validation checks should not be reached on a
// real Nomad cluster as all of this data should be validated when registering
// volumes with the cluster. They serve as a defensive check before forwarding
// requests to plugins, and to aid with development.
if req.VolumeID == "" {
return errors.New("CSI.ControllerAttachVolume: VolumeID is required")
}
if req.ClientCSINodeID == "" {
return errors.New("CSI.ControllerAttachVolume: ClientCSINodeID is required")
}
csiReq, err := req.ToCSIRequest()
if err != nil {
return fmt.Errorf("CSI.ControllerAttachVolume: %v", err)
}
// Submit the request for a volume to the CSI Plugin.
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerPublishVolume errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
cresp, err := plugin.ControllerPublishVolume(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if err != nil {
return fmt.Errorf("CSI.ControllerAttachVolume: %v", err)
}
resp.PublishContext = cresp.PublishContext
return nil
}
// ControllerDetachVolume is used to detach a volume from a CSI Cluster from
// the storage node provided in the request.
func (c *CSI) ControllerDetachVolume(req *structs.ClientCSIControllerDetachVolumeRequest, resp *structs.ClientCSIControllerDetachVolumeResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "unpublish_volume"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerDetachVolume: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
// The following block of validation checks should not be reached on a
// real Nomad cluster as all of this data should be validated when registering
// volumes with the cluster. They serve as a defensive check before forwarding
// requests to plugins, and to aid with development.
if req.VolumeID == "" {
return errors.New("CSI.ControllerDetachVolume: VolumeID is required")
}
if req.ClientCSINodeID == "" {
return errors.New("CSI.ControllerDetachVolume: ClientCSINodeID is required")
}
csiReq := req.ToCSIRequest()
// Submit the request for a volume to the CSI Plugin.
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerUnpublishVolume errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
_, err = plugin.ControllerUnpublishVolume(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if errors.Is(err, nstructs.ErrCSIClientRPCIgnorable) {
// if the controller detach previously happened but the server failed to
// checkpoint, we'll get an error from the plugin but can safely ignore it.
c.c.logger.Debug("could not unpublish volume", "error", err)
return nil
}
if err != nil {
return fmt.Errorf("CSI.ControllerDetachVolume: %v", err)
}
return err
}
func (c *CSI) ControllerCreateVolume(req *structs.ClientCSIControllerCreateVolumeRequest, resp *structs.ClientCSIControllerCreateVolumeResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "create_volume"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerCreateVolume: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq, err := req.ToCSIRequest()
if err != nil {
return fmt.Errorf("CSI.ControllerCreateVolume: %v", err)
}
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerCreateVolume errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
cresp, err := plugin.ControllerCreateVolume(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if err != nil {
return fmt.Errorf("CSI.ControllerCreateVolume: %v", err)
}
if cresp == nil || cresp.Volume == nil {
c.c.logger.Warn("plugin did not return error or volume; this is a bug in the plugin and should be reported to the plugin author")
return fmt.Errorf("CSI.ControllerCreateVolume: plugin did not return error or volume")
}
resp.ExternalVolumeID = cresp.Volume.ExternalVolumeID
resp.CapacityBytes = cresp.Volume.CapacityBytes
resp.VolumeContext = cresp.Volume.VolumeContext
return nil
}
func (c *CSI) ControllerDeleteVolume(req *structs.ClientCSIControllerDeleteVolumeRequest, resp *structs.ClientCSIControllerDeleteVolumeResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "delete_volume"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerDeleteVolume: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq := req.ToCSIRequest()
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerDeleteVolume errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
err = plugin.ControllerDeleteVolume(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if errors.Is(err, nstructs.ErrCSIClientRPCIgnorable) {
// if the volume was deleted out-of-band, we'll get an error from
// the plugin but can safely ignore it
c.c.logger.Debug("could not delete volume", "error", err)
return nil
}
if err != nil {
return fmt.Errorf("CSI.ControllerDeleteVolume: %v", err)
}
return err
}
func (c *CSI) ControllerListVolumes(req *structs.ClientCSIControllerListVolumesRequest, resp *structs.ClientCSIControllerListVolumesResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "list_volumes"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerListVolumes: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq := req.ToCSIRequest()
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerListVolumes errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
cresp, err := plugin.ControllerListVolumes(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if err != nil {
return fmt.Errorf("CSI.ControllerListVolumes: %v", err)
}
resp.NextToken = cresp.NextToken
resp.Entries = []*nstructs.CSIVolumeExternalStub{}
for _, entry := range cresp.Entries {
if entry.Volume == nil {
return fmt.Errorf("CSI.ControllerListVolumes: plugin returned an invalid entry")
}
vol := &nstructs.CSIVolumeExternalStub{
ExternalID: entry.Volume.ExternalVolumeID,
CapacityBytes: entry.Volume.CapacityBytes,
VolumeContext: entry.Volume.VolumeContext,
CloneID: entry.Volume.ContentSource.CloneID,
SnapshotID: entry.Volume.ContentSource.SnapshotID,
}
if entry.Status != nil {
vol.PublishedExternalNodeIDs = entry.Status.PublishedNodeIds
vol.IsAbnormal = entry.Status.VolumeCondition.Abnormal
if entry.Status.VolumeCondition != nil {
vol.Status = entry.Status.VolumeCondition.Message
}
}
resp.Entries = append(resp.Entries, vol)
if req.MaxEntries != 0 && int32(len(resp.Entries)) == req.MaxEntries {
break
}
}
return nil
}
func (c *CSI) ControllerCreateSnapshot(req *structs.ClientCSIControllerCreateSnapshotRequest, resp *structs.ClientCSIControllerCreateSnapshotResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "create_snapshot"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerCreateSnapshot: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq, err := req.ToCSIRequest()
if err != nil {
return fmt.Errorf("CSI.ControllerCreateSnapshot: %v", err)
}
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerCreateSnapshot errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
cresp, err := plugin.ControllerCreateSnapshot(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if err != nil {
return fmt.Errorf("CSI.ControllerCreateSnapshot: %v", err)
}
if cresp == nil || cresp.Snapshot == nil {
c.c.logger.Warn("plugin did not return error or snapshot; this is a bug in the plugin and should be reported to the plugin author")
return fmt.Errorf("CSI.ControllerCreateSnapshot: plugin did not return error or snapshot")
}
resp.ID = cresp.Snapshot.ID
resp.ExternalSourceVolumeID = cresp.Snapshot.SourceVolumeID
resp.SizeBytes = cresp.Snapshot.SizeBytes
resp.CreateTime = cresp.Snapshot.CreateTime
resp.IsReady = cresp.Snapshot.IsReady
return nil
}
func (c *CSI) ControllerDeleteSnapshot(req *structs.ClientCSIControllerDeleteSnapshotRequest, resp *structs.ClientCSIControllerDeleteSnapshotResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "delete_snapshot"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerDeleteSnapshot: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq := req.ToCSIRequest()
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerDeleteSnapshot errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
err = plugin.ControllerDeleteSnapshot(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if errors.Is(err, nstructs.ErrCSIClientRPCIgnorable) {
// if the snapshot was deleted out-of-band, we'll get an error from
// the plugin but can safely ignore it
c.c.logger.Debug("could not delete snapshot", "error", err)
return nil
}
if err != nil {
return fmt.Errorf("CSI.ControllerDeleteSnapshot: %v", err)
}
return err
}
func (c *CSI) ControllerListSnapshots(req *structs.ClientCSIControllerListSnapshotsRequest, resp *structs.ClientCSIControllerListSnapshotsResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_controller", "list_snapshots"}, time.Now())
plugin, err := c.findControllerPlugin(req.PluginID)
if err != nil {
// the server's view of the plugin health is stale, so let it know it
// should retry with another controller instance
return fmt.Errorf("CSI.ControllerListSnapshots: %w: %v",
nstructs.ErrCSIClientRPCRetryable, err)
}
defer plugin.Close()
csiReq := req.ToCSIRequest()
ctx, cancelFn := c.requestContext()
defer cancelFn()
// CSI ControllerListSnapshots errors for timeout, codes.Unavailable and
// codes.ResourceExhausted are retried; all other errors are fatal.
cresp, err := plugin.ControllerListSnapshots(ctx, csiReq,
grpc_retry.WithPerRetryTimeout(CSIPluginRequestTimeout),
grpc_retry.WithMax(3),
grpc_retry.WithBackoff(grpc_retry.BackoffExponential(100*time.Millisecond)))
if err != nil {
return fmt.Errorf("CSI.ControllerListSnapshots: %v", err)
}
resp.NextToken = cresp.NextToken
resp.Entries = []*nstructs.CSISnapshot{}
for _, entry := range cresp.Entries {
if entry.Snapshot == nil {
return fmt.Errorf("CSI.ControllerListSnapshot: plugin returned an invalid entry")
}
snap := &nstructs.CSISnapshot{
ID: entry.Snapshot.ID,
ExternalSourceVolumeID: entry.Snapshot.SourceVolumeID,
SizeBytes: entry.Snapshot.SizeBytes,
CreateTime: entry.Snapshot.CreateTime,
IsReady: entry.Snapshot.IsReady,
PluginID: req.PluginID,
}
resp.Entries = append(resp.Entries, snap)
if req.MaxEntries != 0 && int32(len(resp.Entries)) == req.MaxEntries {
break
}
}
return nil
}
// NodeDetachVolume is used to detach a volume from a CSI Cluster from
// the storage node provided in the request.
func (c *CSI) NodeDetachVolume(req *structs.ClientCSINodeDetachVolumeRequest, resp *structs.ClientCSINodeDetachVolumeResponse) error {
defer metrics.MeasureSince([]string{"client", "csi_node", "detach_volume"}, time.Now())
// The following block of validation checks should not be reached on a
// real Nomad cluster. They serve as a defensive check before forwarding
// requests to plugins, and to aid with development.
if req.PluginID == "" {
return errors.New("CSI.NodeDetachVolume: PluginID is required")
}
if req.VolumeID == "" {
return errors.New("CSI.NodeDetachVolume: VolumeID is required")
}
if req.AllocID == "" {
return errors.New("CSI.NodeDetachVolume: AllocID is required")
}
ctx, cancelFn := c.requestContext()
defer cancelFn()
mounter, err := c.c.csimanager.MounterForPlugin(ctx, req.PluginID)
if err != nil {
return fmt.Errorf("CSI.NodeDetachVolume: %v", err)
}
usageOpts := &csimanager.UsageOptions{
ReadOnly: req.ReadOnly,
AttachmentMode: string(req.AttachmentMode),
AccessMode: string(req.AccessMode),
}
err = mounter.UnmountVolume(ctx, req.VolumeID, req.ExternalID, req.AllocID, usageOpts)
if err != nil && !errors.Is(err, nstructs.ErrCSIClientRPCIgnorable) {
// if the unmounting previously happened but the server failed to
// checkpoint, we'll get an error from Unmount but can safely
// ignore it.
return fmt.Errorf("CSI.NodeDetachVolume: %v", err)
}
return nil
}
func (c *CSI) findControllerPlugin(name string) (csi.CSIPlugin, error) {
return c.findPlugin(dynamicplugins.PluginTypeCSIController, name)
}
func (c *CSI) findPlugin(ptype, name string) (csi.CSIPlugin, error) {
pIface, err := c.c.dynamicRegistry.DispensePlugin(ptype, name)
if err != nil {
return nil, err
}
plugin, ok := pIface.(csi.CSIPlugin)
if !ok {
return nil, ErrPluginTypeError
}
return plugin, nil
}
func (c *CSI) requestContext() (context.Context, context.CancelFunc) {
return context.WithTimeout(context.Background(), CSIPluginRequestTimeout)
}