Merge pull request #3 from bakins/k8s-1.6

rewrite for 1.6

attach.go

@@ -0,0 +1,184 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"path"
+	"strconv"
+	"strings"
+
+	zfs "github.com/bakins/go-zfs"
+	units "github.com/docker/go-units"
+	"github.com/spf13/cobra"
+)
+
+var attachCmd = &cobra.Command{
+	Use:   "attach <json params> <nodename>",
+	Short: "Attach the volume specified by the given spec on the given host.",
+	Run:   runAttachCmd,
+}
+
+var isAttachedCmd = &cobra.Command{
+	Use:   "isattached <json options> <node name>",
+	Short: "Check the volume is attached on the node.",
+	Run:   runIsAttached,
+}
+
+var waitForAttachCmd = &cobra.Command{
+	Use:   "waitforattach <mount device> <json params>",
+	Short: "Wait for the volume to be attached on the remote node",
+	Run:   runWaitForAttachCmd,
+}
+
+var detachCmd = &cobra.Command{
+	Use:   "detach <mount device> <node name>",
+	Short: "Detach the volume from the Kubelet node.",
+	Run:   runDetachCmd,
+}
+
+func runWaitForAttachCmd(cmd *cobra.Command, args []string) {
+	r := result{}
+	if len(args) < 2 {
+		r.emit(-2, cmd.Use)
+		return
+	}
+
+	var p params
+	if err := json.Unmarshal([]byte(args[1]), &p); err != nil {
+		r.emit(-1, fmt.Sprintf("unable to unmarshal json: %v", err))
+		return
+	}
+
+	if p.Dataset == "" {
+		r.emit(-2, "dataset is required")
+		return
+	}
+
+	r.Device = path.Join(getParent(), p.Dataset)
+
+	if r.Device != args[0] {
+		r.emit(-6, fmt.Sprintf("devices do not match: %s != %s", args[0], r.Device))
+	}
+
+	// does the volume already exist?
+	ds, err := zfs.GetDataset(r.Device)
+	if err != nil {
+		r.error(err)
+		return
+	}
+
+	if ds.Type != "filesystem" {
+		r.emit(-3, "existing dataset is not a filesystem")
+		return
+	}
+	// XXX: we will not alter existing volumes for now
+	r.emit(0, "found existing filesystem")
+	return
+}
+
+func runAttachCmd(cmd *cobra.Command, args []string) {
+	r := result{}
+
+	// node is second argument, but could be optional?
+	if len(args) < 1 {
+		r.emit(-2, cmd.Use)
+		return
+	}
+
+	var p params
+	if err := json.Unmarshal([]byte(args[0]), &p); err != nil {
+		r.emit(-1, fmt.Sprintf("unable to unmarshal json: %v", err))
+		return
+	}
+
+	if p.Dataset == "" {
+		r.emit(-2, "dataset is required")
+		return
+	}
+
+	if p.Quota == "" {
+		r.emit(-2, "quota is required")
+		return
+	}
+
+	if p.Reservation == "" {
+		p.Reservation = "0"
+	}
+
+	quota, err := units.RAMInBytes(p.Quota)
+	if err != nil {
+		r.emit(-2, fmt.Sprintf("unable to parse quota: %v", err))
+		return
+	}
+	if quota <= 0 {
+		r.emit(-2, "quota must be greater than 0")
+		return
+	}
+
+	reservation, err := units.RAMInBytes(p.Reservation)
+	if err != nil {
+		r.emit(-2, fmt.Sprintf("unable to parse reservation: %v", err))
+		return
+	}
+
+	if quota < reservation {
+		r.emit(-2, "quota must be greater than or equal to reservation")
+		return
+	}
+
+	options := make(map[string]string)
+	options["quota"] = strconv.FormatInt(quota, 10)
+	if reservation > 0 {
+		options["reservation"] = strconv.FormatInt(reservation, 10)
+	}
+
+	if p.Compression != "" {
+		options["compression"] = p.Compression
+	}
+
+	r.Device = path.Join(getParent(), p.Dataset)
+	// does the volume already exist?
+	ds, err := zfs.GetDataset(r.Device)
+	if err == nil {
+		if ds.Type != "filesystem" {
+			r.emit(-3, "existing dataset is not a filesystem")
+			return
+		}
+		// XXX: we will not alter existing volumes for now
+		r.emit(0, "found existing filesystem")
+		return
+	}
+
+	// HACK: zfs package provides no way to check if it not found
+	if !strings.Contains(err.Error(), "does not exist") {
+		r.emit(-3, fmt.Sprintf("failed to check for filesystem: %v", err))
+		return
+	}
+
+	if _, err := zfs.CreateFilesystem(r.Device, options); err != nil {
+		r.emit(-4, fmt.Sprintf("failed to create filesystem: %v", err))
+		return
+	}
+
+	r.emit(0, "created filesystem")
+}
+
+func runDetachCmd(cmd *cobra.Command, args []string) {
+	// XXX: we do not currenlty delete datasets. perhaps
+	// set an option to do so
+	result{}.emit(0, "")
+}
+
+func runIsAttached(cmd *cobra.Command, args []string) {
+	r := result{Attached: true}
+	// https://github.com/kubernetes/kubernetes/blob/master/examples/volumes/flexvolume/lvm
+	// just returns true
+	r.emit(0, "")
+}
+
+func init() {
+	rootCmd.AddCommand(attachCmd)
+	rootCmd.AddCommand(isAttachedCmd)
+	rootCmd.AddCommand(waitForAttachCmd)
+	rootCmd.AddCommand(detachCmd)
+}

glide.yaml

@@ -6,3 +6,4 @@ import:
   version: 13c707182a3c3015b7516d28985d879d67fca763
 - package: github.com/pborman/uuid
   version: ^1.0.0
+- package: github.com/spf13/cobra

init.go

@@ -0,0 +1,15 @@
+package main
+
+import "github.com/spf13/cobra"
+
+var initCmd = &cobra.Command{
+	Use:   "init",
+	Short: "initialize the driver",
+	Run: func(cmd *cobra.Command, args []string) {
+		result{}.emit(0, "")
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(initCmd)
+}