nodeserver.go

/*
Copyright 2017 The Kubernetes Authors.

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 s3

import (
	"fmt"
	"os"
	"os/exec"

	"golang.org/x/net/context"
	"k8s.io/klog/v2"

	"github.com/container-storage-interface/spec/lib/go/csi"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"

	csicommon "github.com/kubernetes-csi/drivers/pkg/csi-common"
)

type nodeServer struct {
	*csicommon.DefaultNodeServer
}

func (ns *nodeServer) NodePublishVolume(ctx context.Context, req *csi.NodePublishVolumeRequest) (*csi.NodePublishVolumeResponse, error) {
	volumeID := req.GetVolumeId()
	targetPath := req.GetTargetPath()
	stagingTargetPath := req.GetStagingTargetPath()
	klog.Infof("publish volume volumeId:%v  target:%v staging:%v", volumeID, targetPath, stagingTargetPath)

	// Check arguments
	if req.GetVolumeCapability() == nil {
		return nil, status.Error(codes.InvalidArgument, "Volume capability missing in request")
	}
	if len(volumeID) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Volume ID missing in request")
	}
	if len(stagingTargetPath) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Staging Target path missing in request")
	}
	if len(targetPath) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Target path missing in request")
	}

	if _, err := os.Stat(targetPath); os.IsNotExist(err) {
		klog.Infof("target directory %s does not exist creating...", targetPath)
		err := os.MkdirAll(targetPath, 0777)
		if err != nil {
			return nil, status.Error(codes.Internal, fmt.Sprintf("unable to create mkdir directory for  err:%v", err))
		}
	}

	if _, err := os.Stat(targetPath); os.IsNotExist(err) {
		klog.Infof("staging directory %s does not exist creating...", stagingTargetPath)
		err = os.MkdirAll(stagingTargetPath, 0777)
		if err != nil {
			return nil, status.Error(codes.Internal, fmt.Sprintf("unable to create mkdir directory for  err:%v", err))
		}
	}

	deviceID := ""
	if req.GetPublishContext() != nil {
		deviceID = req.GetPublishContext()[deviceID]
	}

	// TODO: Implement readOnly & mountFlags
	readOnly := req.GetReadonly()
	// TODO: check if attrib is correct with context.
	attrib := req.GetVolumeContext()
	mountFlags := req.GetVolumeCapability().GetMount().GetMountFlags()

	klog.Infof("target:%v device:%v readonly:%v volumeId:%v attributes:%v mountflags:%v",
		targetPath, deviceID, readOnly, volumeID, attrib, mountFlags)

	s3, err := newS3ClientFromSecrets(req.GetSecrets())
	if err != nil {
		return nil, fmt.Errorf("failed to initialize S3 client: %w", err)
	}
	meta, err := s3.getMetadata(volumeID)
	if err != nil {
		return nil, err
	}

	mounter := newMounter(meta, s3.cfg)
	if err := mounter.Mount(stagingTargetPath, targetPath); err != nil {
		return nil, err
	}

	klog.Infof("s3 bucket %q successfully mounted to %q", meta.Name, targetPath)

	return &csi.NodePublishVolumeResponse{}, nil
}

func (ns *nodeServer) NodeUnpublishVolume(ctx context.Context, req *csi.NodeUnpublishVolumeRequest) (*csi.NodeUnpublishVolumeResponse, error) {
	volumeID := req.GetVolumeId()
	targetPath := req.GetTargetPath()
	klog.Infof("unpublish volume volumeId:%v  target:%v", volumeID, targetPath)

	// Check arguments
	if len(volumeID) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Volume ID missing in request")
	}
	if len(targetPath) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Target path missing in request")
	}

	cmd := exec.Command("umount", "--lazy", "--force", targetPath)
	out, err := cmd.CombinedOutput()
	if err != nil {
		return nil, status.Error(codes.Internal, fmt.Sprintf("unable to umount %q output:%s err:%v", targetPath, string(out), err))
	}
	klog.Infof("s3 bucket %q has been unmounted.", volumeID)

	return &csi.NodeUnpublishVolumeResponse{}, nil
}

func (ns *nodeServer) NodeStageVolume(ctx context.Context, req *csi.NodeStageVolumeRequest) (*csi.NodeStageVolumeResponse, error) {
	volumeID := req.GetVolumeId()
	stagingTargetPath := req.GetStagingTargetPath()
	klog.Infof("stage volume volumeId:%v stage:%v", volumeID, stagingTargetPath)

	// Check arguments
	if len(volumeID) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Volume ID missing in request")
	}

	if len(stagingTargetPath) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Target path missing in request")
	}

	if req.VolumeCapability == nil {
		return nil, status.Error(codes.InvalidArgument, "NodeStageVolume Volume Capability must be provided")
	}

	err := os.MkdirAll(stagingTargetPath, 0777)
	if err != nil {
		return nil, status.Error(codes.Internal, fmt.Sprintf("unable to create mkdir directory for %q err:%v", stagingTargetPath, err))
	}
	s3, err := newS3ClientFromSecrets(req.GetSecrets())
	if err != nil {
		return nil, fmt.Errorf("failed to initialize s3 client: %w", err)
	}
	meta, err := s3.getMetadata(volumeID)
	if err != nil {
		return nil, err
	}
	mounter := newMounter(meta, s3.cfg)
	if err := mounter.Stage(stagingTargetPath); err != nil {
		return nil, err
	}

	return &csi.NodeStageVolumeResponse{}, nil
}

func (ns *nodeServer) NodeUnstageVolume(ctx context.Context, req *csi.NodeUnstageVolumeRequest) (*csi.NodeUnstageVolumeResponse, error) {
	volumeID := req.GetVolumeId()
	stagingTargetPath := req.GetStagingTargetPath()
	klog.Infof("unstage volume volumeId:%v stage:%v", volumeID, stagingTargetPath)

	// Check arguments
	if len(volumeID) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Volume ID missing in request")
	}
	if len(stagingTargetPath) == 0 {
		return nil, status.Error(codes.InvalidArgument, "Target path missing in request")
	}

	return &csi.NodeUnstageVolumeResponse{}, nil
}

// NodeGetCapabilities returns the supported capabilities of the node server
func (ns *nodeServer) NodeGetCapabilities(ctx context.Context, req *csi.NodeGetCapabilitiesRequest) (*csi.NodeGetCapabilitiesResponse, error) {
	// currently there is a single NodeServer capability according to the spec
	nscap := &csi.NodeServiceCapability{
		Type: &csi.NodeServiceCapability_Rpc{
			Rpc: &csi.NodeServiceCapability_RPC{
				Type: csi.NodeServiceCapability_RPC_STAGE_UNSTAGE_VOLUME,
			},
		},
	}

	return &csi.NodeGetCapabilitiesResponse{
		Capabilities: []*csi.NodeServiceCapability{
			nscap,
		},
	}, nil
}

func (ns *nodeServer) NodeExpandVolume(ctx context.Context, req *csi.NodeExpandVolumeRequest) (*csi.NodeExpandVolumeResponse, error) {
	return &csi.NodeExpandVolumeResponse{}, status.Error(codes.Unimplemented, "NodeExpandVolume is not implemented")
}