Restructure workspace and driver packages

Author: Harvey Lowndes

pkg/oci/driver/block/block_driver.go

@@ -0,0 +1,247 @@
+// Copyright 2017 Oracle and/or its affiliates. All rights reserved.
+//
+// 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 block
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/oracle/oci-flexvolume-driver/pkg/flexvolume"
+	"github.com/oracle/oci-flexvolume-driver/pkg/iscsi"
+	"github.com/oracle/oci-flexvolume-driver/pkg/oci/client"
+	"github.com/oracle/oci-flexvolume-driver/pkg/oci/driver"
+
+	"github.com/oracle/oci-go-sdk/core"
+)
+
+const (
+	// FIXME: Assume lun 1 for now?? Can we get the LUN via the API?
+	diskIDByPathTemplate = "/dev/disk/by-path/ip-%s:%d-iscsi-%s-lun-1"
+)
+
+// OCIFlexvolumeDriver implements the flexvolume.Driver interface for OCI.
+type OCIFlexvolumeDriver struct{}
+
+func init() {
+	driver.RegisterDriver("oci-bvs", &OCIFlexvolumeDriver{})
+}
+
+// Init checks that we have the appropriate credentials and metadata API access
+// on driver initialisation.
+func (d OCIFlexvolumeDriver) Init() flexvolume.DriverStatus {
+	configPath := driver.GetConfigPath()
+
+	if _, err := os.Stat(configPath); !os.IsNotExist(err) {
+		_, err = client.New(configPath)
+		if err != nil {
+			return flexvolume.Fail(err)
+		}
+	} else {
+		log.Printf("Config file %q does not exist. Assuming worker node.", configPath)
+	}
+
+	return flexvolume.Succeed()
+}
+
+// Attach initiates the attachment of the given OCI volume to the k8s worker
+// node.
+func (d OCIFlexvolumeDriver) Attach(opts flexvolume.Options, nodeName string) flexvolume.DriverStatus {
+	c, err := client.New(driver.GetConfigPath())
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	instance, err := c.GetInstanceByNodeName(nodeName)
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	volumeOCID := driver.DeriveVolumeOCID(c.GetConfig().Auth.RegionKey, opts["kubernetes.io/pvOrVolumeName"])
+
+	log.Printf("Attaching volume %s -> instance %s", volumeOCID, *instance.Id)
+
+	attachment, statusCode, err := c.AttachVolume(*instance.Id, volumeOCID)
+	if err != nil {
+		if statusCode != 409 {
+			log.Printf("AttachVolume: %+v", err)
+			return flexvolume.Fail(err)
+		}
+		// If we get a 409 conflict response when attaching we
+		// presume that the device is already attached.
+		log.Printf("Attach(): Volume %q already attached.", volumeOCID)
+		attachment, err = c.FindVolumeAttachment(volumeOCID)
+		if err != nil {
+			return flexvolume.Fail(err)
+		}
+		if *attachment.GetInstanceId() != *instance.Id {
+			return flexvolume.Fail("Already attached to instance: ", *instance.Id)
+		}
+	}
+
+	attachment, err = c.WaitForVolumeAttached(*attachment.GetId())
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	log.Printf("attach: %s attached", *attachment.GetId())
+	iscsiAttachment, ok := attachment.(core.IScsiVolumeAttachment)
+	if !ok {
+		return flexvolume.Fail("Only ISCSI volume attachments are currently supported")
+	}
+
+	return flexvolume.DriverStatus{
+		Status: flexvolume.StatusSuccess,
+		Device: fmt.Sprintf(diskIDByPathTemplate, *iscsiAttachment.Ipv4, *iscsiAttachment.Port, *iscsiAttachment.Iqn),
+	}
+}
+
+// Detach detaches the volume from the worker node.
+func (d OCIFlexvolumeDriver) Detach(pvOrVolumeName, nodeName string) flexvolume.DriverStatus {
+	c, err := client.New(driver.GetConfigPath())
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	volumeOCID := driver.DeriveVolumeOCID(c.GetConfig().Auth.RegionKey, pvOrVolumeName)
+	attachment, err := c.FindVolumeAttachment(volumeOCID)
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	err = c.DetachVolume(*attachment.GetId())
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	err = c.WaitForVolumeDetached(*attachment.GetId())
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+	return flexvolume.Succeed()
+}
+
+// WaitForAttach searches for the the volume attachment created by Attach() and
+// waits for its life cycle state to reach ATTACHED.
+func (d OCIFlexvolumeDriver) WaitForAttach(mountDevice string, _ flexvolume.Options) flexvolume.DriverStatus {
+	return flexvolume.DriverStatus{
+		Status: flexvolume.StatusSuccess,
+		Device: mountDevice,
+	}
+}
+
+// IsAttached checks whether the volume is attached to the host.
+// TODO(apryde): The documentation states that this is called from the Kubelet
+// and KCM. Implementation requries credentials which won't be present on nodes
+// but I've only ever seen it called by the KCM.
+func (d OCIFlexvolumeDriver) IsAttached(opts flexvolume.Options, nodeName string) flexvolume.DriverStatus {
+	c, err := client.New(driver.GetConfigPath())
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	volumeOCID := driver.DeriveVolumeOCID(c.GetConfig().Auth.RegionKey, opts["kubernetes.io/pvOrVolumeName"])
+	attachment, err := c.FindVolumeAttachment(volumeOCID)
+	if err != nil {
+		return flexvolume.DriverStatus{
+			Status:   flexvolume.StatusSuccess,
+			Message:  err.Error(),
+			Attached: false,
+		}
+	}
+
+	log.Printf("attach: found volume attachment %s", *attachment.GetId())
+
+	return flexvolume.DriverStatus{
+		Status:   flexvolume.StatusSuccess,
+		Attached: true,
+	}
+}
+
+// MountDevice connects the iSCSI target on the k8s worker node before mounting
+// and (if necessary) formatting the disk.
+func (d OCIFlexvolumeDriver) MountDevice(mountDir, mountDevice string, opts flexvolume.Options) flexvolume.DriverStatus {
+	iSCSIMounter, err := iscsi.NewFromDevicePath(mountDevice)
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	if isMounted, oErr := iSCSIMounter.DeviceOpened(mountDevice); oErr != nil {
+		return flexvolume.Fail(oErr)
+	} else if isMounted {
+		return flexvolume.Succeed("Device already mounted. Nothing to do.")
+	}
+
+	if err = iSCSIMounter.AddToDB(); err != nil {
+		return flexvolume.Fail(err)
+	}
+	if err = iSCSIMounter.SetAutomaticLogin(); err != nil {
+		return flexvolume.Fail(err)
+	}
+	if err = iSCSIMounter.Login(); err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	if !waitForPathToExist(mountDevice, 20) {
+		return flexvolume.Fail("Failed waiting for device to exist: ", mountDevice)
+	}
+
+	options := []string{}
+	if opts[flexvolume.OptionReadWrite] == "ro" {
+		options = []string{"ro"}
+	}
+	err = iSCSIMounter.FormatAndMount(mountDevice, mountDir, opts[flexvolume.OptionFSType], options)
+	if err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	return flexvolume.Succeed()
+}
+
+// UnmountDevice unmounts the disk, logs out the iscsi target, and deletes the
+// iscsi node record.
+func (d OCIFlexvolumeDriver) UnmountDevice(mountPath string) flexvolume.DriverStatus {
+	iSCSIMounter, err := iscsi.NewFromMountPointPath(mountPath)
+	if err != nil {
+		if err == iscsi.ErrMountPointNotFound {
+			return flexvolume.Succeed("Mount point not found. Nothing to do.")
+		}
+		return flexvolume.Fail(err)
+	}
+
+	if err = iSCSIMounter.UnmountPath(mountPath); err != nil {
+		return flexvolume.Fail(err)
+	}
+	if err = iSCSIMounter.Logout(); err != nil {
+		return flexvolume.Fail(err)
+	}
+	if err = iSCSIMounter.RemoveFromDB(); err != nil {
+		return flexvolume.Fail(err)
+	}
+
+	return flexvolume.Succeed()
+}
+
+// Mount is unimplemented as we use the --enable-controller-attach-detach flow
+// and as such mount the drive in MountDevice().
+func (d OCIFlexvolumeDriver) Mount(mountDir string, opts flexvolume.Options) flexvolume.DriverStatus {
+	return flexvolume.NotSupported()
+}
+
+// Unmount is unimplemented as we use the --enable-controller-attach-detach flow
+// and as such unmount the drive in UnmountDevice().
+func (d OCIFlexvolumeDriver) Unmount(mountDir string) flexvolume.DriverStatus {
+	return flexvolume.NotSupported()
+}

pkg/oci/driver/utils.go renamed to pkg/oci/driver/block/utils.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package driver
+package block
 
 import (
 	"os"