Support publishing as Docker Engine managed plugin

.dockerignore

@@ -0,0 +1,4 @@
+*
+!/plugin/
+!/etc/docker/docker-lvm-plugin
+!/docker-lvm-plugin

.gitignore

@@ -24,4 +24,5 @@ _testmain.go
 *.prof
 
 .vagrant/
+plugin/rootfs
 docker-lvm-plugin

README.md

@@ -9,7 +9,10 @@ This plugin can be used to create lvm volumes of specified size, which can
 then be bind mounted into the container using `docker run` command.
 
 ## Setup
+### Using Docker
+    docker plugin install --alias lvm containers/docker-lvm-plugin/docker-lvm-plugin VOLUME_GROUP=vg0
 
+### Manual
     1) git clone [email protected]:projectatomic/docker-lvm-plugin.git (You can also use HTTPS to clone: git clone https://github.com/projectatomic/docker-lvm-plugin.git)
     2) cd docker-lvm-plugin
     3) export GO111MODULE=on

driver.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"fmt"
-	"log/syslog"
+	"log"
 	"os"
 	"os/exec"
 	"sync"
@@ -19,7 +19,7 @@ type lvmDriver struct {
 	volumes  map[string]*vol
 	count    map[string]int
 	mu       sync.RWMutex
-	logger   *syslog.Writer
+	logger   *log.Logger
 }
 
 type vol struct {
@@ -32,10 +32,10 @@ type vol struct {
 }
 
 func newDriver(home, vgConfig string) (*lvmDriver, error) {
-	logger, err := syslog.New(syslog.LOG_ERR, "docker-lvm-plugin")
-	if err != nil {
-		return nil, err
-	}
+	logger := log.New(os.Stdout, "docker-lvm-plugin", 1)
+	//if err != nil {
+	//	return nil, err
+	//}
 
 	return &lvmDriver{
 		home:     home,
@@ -82,7 +82,7 @@ func (l *lvmDriver) Create(req *volume.CreateRequest) error {
 			return fmt.Errorf("Please don't specify --opt keyfile= for snapshots")
 		}
 		if isThinSnap, _, err = isThinlyProvisioned(vgName, snap); err != nil {
-			l.logger.Err(fmt.Sprintf("Create: lvdisplayGrep error: %v", err))
+			l.logger.Print(fmt.Sprintf("Create: lvdisplayGrep error: %v", err))
 			return fmt.Errorf("Error creating volume")
 		}
 	}
@@ -123,7 +123,7 @@ func (l *lvmDriver) Create(req *volume.CreateRequest) error {
 	}
 	cmd := exec.Command("lvcreate", cmdArgs...)
 	if out, err := cmd.CombinedOutput(); err != nil {
-		l.logger.Err(fmt.Sprintf("Create: lvcreate error: %s output %s", err, string(out)))
+		l.logger.Print(fmt.Sprintf("Create: lvcreate error: %s output %s", err, string(out)))
 		return fmt.Errorf("Error creating volume")
 	}
 
@@ -139,19 +139,19 @@ func (l *lvmDriver) Create(req *volume.CreateRequest) error {
 		if hasKeyFile {
 			cmd = exec.Command("cryptsetup", "-q", "-d", keyFile, "luksFormat", device)
 			if out, err := cmd.CombinedOutput(); err != nil {
-				l.logger.Err(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
+				l.logger.Print(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
 				return fmt.Errorf("Error encrypting volume")
 			}
 
 			if out, err := luksOpen(vgName, req.Name, keyFile); err != nil {
-				l.logger.Err(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
+				l.logger.Print(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
 				return fmt.Errorf("Error opening encrypted volume")
 			}
 
 			defer func() {
 				if err != nil {
 					if out, err := luksClose(req.Name); err != nil {
-						l.logger.Err(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
+						l.logger.Print(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
 					}
 				}
 			}()
@@ -161,13 +161,13 @@ func (l *lvmDriver) Create(req *volume.CreateRequest) error {
 
 		cmd = exec.Command("mkfs.xfs", device)
 		if out, err := cmd.CombinedOutput(); err != nil {
-			l.logger.Err(fmt.Sprintf("Create: mkfs.xfs error: %s output %s", err, string(out)))
+			l.logger.Print(fmt.Sprintf("Create: mkfs.xfs error: %s output %s", err, string(out)))
 			return fmt.Errorf("Error partitioning volume")
 		}
 
 		if hasKeyFile {
 			if out, err := luksClose(req.Name); err != nil {
-				l.logger.Err(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
+				l.logger.Print(fmt.Sprintf("Create: cryptsetup error: %s output %s", err, string(out)))
 				return fmt.Errorf("Error closing encrypted volume")
 			}
 		}
@@ -237,7 +237,7 @@ func (l *lvmDriver) Get(req *volume.GetRequest) (*volume.GetResponse, error) {
 
 	createdAt, err := getVolumeCreationDateTime(v.VgName, v.Name)
 	if err != nil {
-		l.logger.Err(fmt.Sprintf("Get: %v", err))
+		l.logger.Print(fmt.Sprintf("Get: %v", err))
 		return nil, err
 	}
 
@@ -287,7 +287,7 @@ func (l *lvmDriver) Remove(req *volume.RemoveRequest) error {
 	}
 
 	if out, err := removeLogicalVolume(req.Name, vol.VgName); err != nil {
-		l.logger.Err(fmt.Sprintf("Remove: removeLogicalVolume error %s output %s", err, string(out)))
+		l.logger.Print(fmt.Sprintf("Remove: removeLogicalVolume error %s output %s", err, string(out)))
 		return fmt.Errorf("error removing volume")
 	}
 
@@ -334,21 +334,21 @@ func (l *lvmDriver) Mount(req *volume.MountRequest) (*volume.MountResponse, erro
 
 		if keyFile != "" {
 			if err := keyFileExists(keyFile); err != nil {
-				l.logger.Err(fmt.Sprintf("Mount: %s", err))
+				l.logger.Print(fmt.Sprintf("Mount: %s", err))
 				return &volume.MountResponse{}, err
 			}
 			if err := cryptsetupInstalled(); err != nil {
-				l.logger.Err(fmt.Sprintf("Mount: %s", err))
+				l.logger.Print(fmt.Sprintf("Mount: %s", err))
 				return &volume.MountResponse{}, err
 			}
 			if out, err := luksOpen(vol.VgName, req.Name, keyFile); err != nil {
-				l.logger.Err(fmt.Sprintf("Mount: cryptsetup error: %s output %s", err, string(out)))
+				l.logger.Print(fmt.Sprintf("Mount: cryptsetup error: %s output %s", err, string(out)))
 				return &volume.MountResponse{}, fmt.Errorf("Error opening encrypted volume")
 			}
 			defer func() {
 				if err != nil {
 					if out, err := luksClose(req.Name); err != nil {
-						l.logger.Err(fmt.Sprintf("Mount: cryptsetup error: %s output %s", err, string(out)))
+						l.logger.Print(fmt.Sprintf("Mount: cryptsetup error: %s output %s", err, string(out)))
 					}
 				}
 			}()
@@ -361,7 +361,7 @@ func (l *lvmDriver) Mount(req *volume.MountRequest) (*volume.MountResponse, erro
 		}
 		cmd := exec.Command("mount", mountArgs...)
 		if out, err := cmd.CombinedOutput(); err != nil {
-			l.logger.Err(fmt.Sprintf("Mount: mount error: %s output %s", err, string(out)))
+			l.logger.Print(fmt.Sprintf("Mount: mount error: %s output %s", err, string(out)))
 			return &volume.MountResponse{}, fmt.Errorf("Error mouting volume")
 		}
 	}
@@ -379,22 +379,22 @@ func (l *lvmDriver) Unmount(req *volume.UnmountRequest) error {
 		mp := getMountpoint(l.home, req.Name)
 		isVolMounted, err := mount.Mounted(mp)
 		if err != nil {
-			l.logger.Err(fmt.Sprintf("Unmount: %s", err))
+			l.logger.Print(fmt.Sprintf("Unmount: %s", err))
 			return fmt.Errorf("error unmounting volume")
 		}
 		if isVolMounted {
 			cmd := exec.Command("umount", mp)
 			if out, err := cmd.CombinedOutput(); err != nil {
-				l.logger.Err(fmt.Sprintf("Unmount: unmount error: %s output %s", err, string(out)))
+				l.logger.Print(fmt.Sprintf("Unmount: unmount error: %s output %s", err, string(out)))
 				return fmt.Errorf("error unmounting volume")
 			}
 			if v, ok := l.volumes[req.Name]; ok && v.KeyFile != "" {
 				if err := cryptsetupInstalled(); err != nil {
-					l.logger.Err(fmt.Sprintf("Unmount: %s", err))
+					l.logger.Print(fmt.Sprintf("Unmount: %s", err))
 					return err
 				}
 				if out, err := luksClose(req.Name); err != nil {
-					l.logger.Err(fmt.Sprintf("Unmount: cryptsetup error: %s output %s", err, string(out)))
+					l.logger.Print(fmt.Sprintf("Unmount: cryptsetup error: %s output %s", err, string(out)))
 					return fmt.Errorf("Error closing encrypted volume")
 				}
 			}

etc/docker/docker-lvm-plugin

@@ -4,4 +4,4 @@
 # OR create a new volume group using `vgcreate` command. 
 # e.g. vgcreate volume_group_one /dev/hda where /dev/hda is your partition or
 # whole disk on which physical volumes were created.
-VOLUME_GROUP=
+VOLUME_GROUP=foo

plugin/Dockerfile

@@ -0,0 +1,5 @@
+FROM alpine
+RUN apk update && apk add lvm2 xfsprogs cryptsetup thin-provisioning-tools
+RUN mkdir -p /var/lib/docker-lvm-plugin
+COPY etc/docker/docker-lvm-plugin /etc/docker/docker-lvm-plugin
+COPY docker-lvm-plugin /

plugin/Makefile

@@ -0,0 +1,38 @@
+name := containers/docker-lvm-plugin
+
+.PHONY: build
+build: docker-lvm-plugin
+
+docker-lvm-plugin: main.go driver.go utils.go go.mod go.sum
+	docker run --rm --tmpfs /tmp -v $(shell pwd):/tmp/docker-lvm-plugin -w /tmp/docker-lvm-plugin golang:alpine go build
+
+.PHONY: create
+create: plugin/config.json plugin/rootfs
+	docker plugin rm --force $(name) || true
+	docker plugin create $(name) plugin
+
+.PHONY: install
+install: create
+	docker plugin rm --force $(name) || true
+	docker plugin install $(name) --alias lvm --grant-all-permissions
+
+.PHONY: push
+push: create
+	docker plugin push $(name)
+
+.PHONY: enable
+enable: create
+	docker plugin enable $(name)
+
+.PHONY: clean
+clean:
+	rm -rf plugin/rootfs
+
+plugin/rootfs: .dockerignore plugin/Dockerfile docker-lvm-plugin
+	docker build --tag $(name):rootfs -f plugin/Dockerfile .
+	docker rm --force --volumes rootfs || true
+	docker create --name rootfs $(name):rootfs
+	rm -rf $@
+	mkdir -p $@
+	docker export rootfs | tar -x -C $@
+	docker rm --force --volumes rootfs

plugin/config.json

@@ -0,0 +1,36 @@
+{
+    "Description": "LVM volume plugin for Docker",
+    "Documentation": "https://docs.docker.com/engine/extend/plugins/",
+    "Entrypoint": ["/docker-lvm-plugin"],
+    "Env": [
+      {
+        "Name": "VOLUME_GROUP",
+        "Description": "LVM volume group to create volumes in.",
+        "Settable": ["value"],
+        "Value": null
+      }
+    ],
+    "Interface": {
+      "Socket": "lvm.sock",
+      "Types": ["docker.volumedriver/1.0"]
+    },
+    "Linux": {
+      "Capabilities": ["CAP_SYS_ADMIN"],
+      "AllowAllDevices": true,
+      "Devices": null
+    },
+    "Mounts": [
+      {
+        "description": "Device access for devicemapper (/dev/mapper/*, /dev/*/*)",
+        "destination": "/dev",
+        "options": ["rbind"],
+        "name": "dev",
+        "source": "/dev",
+        "type": "bind"
+      }
+    ],
+    "Network": {
+      "Type": "host"
+    },
+    "PropagatedMount": "/var/lib/docker-lvm-plugin"
+}