Support publishing as Docker Engine managed plugin

Signed-off-by: Olli Janatuinen <olli.janatuinen@gmail.com>

Author: olljanat

.circleci/config.yml

@@ -8,3 +8,4 @@ jobs:
       - checkout
       - run: make circleci
       - run: sudo make test
+      - run: make -f plugin/Makefile create

.dockerignore

@@ -0,0 +1,3 @@
+*
+!/plugin/
+!/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 git@github.com: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

plugin/Dockerfile

@@ -0,0 +1,4 @@
+FROM alpine
+RUN apk update && apk add lvm2 xfsprogs cryptsetup thin-provisioning-tools
+RUN mkdir -p /var/lib/docker-lvm-plugin
+COPY docker-lvm-plugin /

plugin/Makefile

@@ -0,0 +1,39 @@
+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:latest 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) --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
+
+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"
+}