graphdriver: Add generic test framework for graph drivers

This adds daemon/graphdriver/graphtest/graphtest which has a few
generic tests for all graph drivers, and then uses these
from the btrs, devicemapper and vfs backends.

I've not yet added the aufs backend, because i can't test that here
atm. It should work though.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)

daemon/graphdriver/btrfs/btrfs_test.go

@@ -0,0 +1,28 @@
+package btrfs
+
+import (
+	"github.com/dotcloud/docker/daemon/graphdriver/graphtest"
+	"testing"
+)
+
+// This avoids creating a new driver for each test if all tests are run
+// Make sure to put new tests between TestBtrfsSetup and TestBtrfsTeardown
+func TestBtrfsSetup(t *testing.T) {
+	graphtest.GetDriver(t, "btrfs")
+}
+
+func TestBtrfsCreateEmpty(t *testing.T) {
+	graphtest.DriverTestCreateEmpty(t, "btrfs")
+}
+
+func TestBtrfsCreateBase(t *testing.T) {
+	graphtest.DriverTestCreateBase(t, "btrfs")
+}
+
+func TestBtrfsCreateSnap(t *testing.T) {
+	graphtest.DriverTestCreateSnap(t, "btrfs")
+}
+
+func TestBtrfsTeardown(t *testing.T) {
+	graphtest.PutDriver(t)
+}

daemon/graphdriver/devmapper/driver_test.go

@@ -5,6 +5,7 @@ package devmapper
 import (
 	"fmt"
 	"github.com/dotcloud/docker/daemon/graphdriver"
+	"github.com/dotcloud/docker/daemon/graphdriver/graphtest"
 	"io/ioutil"
 	"path"
 	"runtime"
@@ -914,3 +915,25 @@ func assertMap(t *testing.T, m map[string]bool, keys ...string) {
 		t.Fatalf("Unexpected keys: %v", m)
 	}
 }
+
+// This avoids creating a new driver for each test if all tests are run
+// Make sure to put new tests between TestDevmapperSetup and TestDevmapperTeardown
+func TestDevmapperSetup(t *testing.T) {
+	graphtest.GetDriver(t, "devicemapper")
+}
+
+func TestDevmapperCreateEmpty(t *testing.T) {
+	graphtest.DriverTestCreateEmpty(t, "devicemapper")
+}
+
+func TestDevmapperCreateBase(t *testing.T) {
+	graphtest.DriverTestCreateBase(t, "devicemapper")
+}
+
+func TestDevmapperCreateSnap(t *testing.T) {
+	graphtest.DriverTestCreateSnap(t, "devicemapper")
+}
+
+func TestDevmapperTeardown(t *testing.T) {
+	graphtest.PutDriver(t)
+}

daemon/graphdriver/graphtest/graphtest.go

@@ -0,0 +1,225 @@
+package graphtest
+
+import (
+	"github.com/dotcloud/docker/daemon/graphdriver"
+	"io/ioutil"
+	"os"
+	"path"
+	"syscall"
+	"testing"
+)
+
+var (
+	drv *Driver
+)
+
+type Driver struct {
+	graphdriver.Driver
+	root     string
+	refCount int
+}
+
+func newDriver(t *testing.T, name string) *Driver {
+	root, err := ioutil.TempDir("/var/tmp", "docker-graphtest-")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := os.MkdirAll(root, 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	d, err := graphdriver.GetDriver(name, root)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return &Driver{d, root, 1}
+}
+
+func cleanup(t *testing.T, d *Driver) {
+	if err := drv.Cleanup(); err != nil {
+		t.Fatal(err)
+	}
+	os.RemoveAll(d.root)
+}
+
+func GetDriver(t *testing.T, name string) graphdriver.Driver {
+	if drv == nil {
+		drv = newDriver(t, name)
+	} else {
+		drv.refCount++
+	}
+	return drv
+}
+
+func PutDriver(t *testing.T) {
+	if drv == nil {
+		t.Fatal("No driver to put!")
+	}
+	drv.refCount--
+	if drv.refCount == 0 {
+		cleanup(t, drv)
+		drv = nil
+	}
+}
+
+func verifyFile(t *testing.T, path string, mode os.FileMode, uid, gid uint32) {
+	fi, err := os.Stat(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if fi.Mode()&os.ModeType != mode&os.ModeType {
+		t.Fatalf("Expected %s type 0x%x, got 0x%x", path, mode&os.ModeType, fi.Mode()&os.ModeType)
+	}
+
+	if fi.Mode()&os.ModePerm != mode&os.ModePerm {
+		t.Fatalf("Expected %s mode %o, got %o", path, mode&os.ModePerm, fi.Mode()&os.ModePerm)
+	}
+
+	if fi.Mode()&os.ModeSticky != mode&os.ModeSticky {
+		t.Fatalf("Expected %s sticky 0x%x, got 0x%x", path, mode&os.ModeSticky, fi.Mode()&os.ModeSticky)
+	}
+
+	if fi.Mode()&os.ModeSetuid != mode&os.ModeSetuid {
+		t.Fatalf("Expected %s setuid 0x%x, got 0x%x", path, mode&os.ModeSetuid, fi.Mode()&os.ModeSetuid)
+	}
+
+	if fi.Mode()&os.ModeSetgid != mode&os.ModeSetgid {
+		t.Fatalf("Expected %s setgid 0x%x, got 0x%x", path, mode&os.ModeSetgid, fi.Mode()&os.ModeSetgid)
+	}
+
+	if stat, ok := fi.Sys().(*syscall.Stat_t); ok {
+		if stat.Uid != uid {
+			t.Fatal("%s no owned by uid %d", path, uid)
+		}
+		if stat.Gid != gid {
+			t.Fatal("%s not owned by gid %d", path, gid)
+		}
+	}
+
+}
+
+// Creates an new image and verifies it is empty and the right metadata
+func DriverTestCreateEmpty(t *testing.T, drivername string) {
+	driver := GetDriver(t, drivername)
+	defer PutDriver(t)
+
+	if err := driver.Create("empty", ""); err != nil {
+		t.Fatal(err)
+	}
+
+	if !driver.Exists("empty") {
+		t.Fatal("Newly created image doesn't exist")
+	}
+
+	dir, err := driver.Get("empty", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	verifyFile(t, dir, 0755|os.ModeDir, 0, 0)
+
+	// Verify that the directory is empty
+	fis, err := ioutil.ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(fis) != 0 {
+		t.Fatal("New directory not empty")
+	}
+
+	driver.Put("empty")
+
+	if err := driver.Remove("empty"); err != nil {
+		t.Fatal(err)
+	}
+
+}
+
+func createBase(t *testing.T, driver graphdriver.Driver, name string) {
+	// We need to be able to set any perms
+	oldmask := syscall.Umask(0)
+	defer syscall.Umask(oldmask)
+
+	if err := driver.Create(name, ""); err != nil {
+		t.Fatal(err)
+	}
+
+	dir, err := driver.Get(name, "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer driver.Put(name)
+
+	subdir := path.Join(dir, "a subdir")
+	if err := os.Mkdir(subdir, 0705|os.ModeSticky); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Chown(subdir, 1, 2); err != nil {
+		t.Fatal(err)
+	}
+
+	file := path.Join(dir, "a file")
+	if err := ioutil.WriteFile(file, []byte("Some data"), 0222|os.ModeSetuid); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func verifyBase(t *testing.T, driver graphdriver.Driver, name string) {
+	dir, err := driver.Get(name, "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer driver.Put(name)
+
+	subdir := path.Join(dir, "a subdir")
+	verifyFile(t, subdir, 0705|os.ModeDir|os.ModeSticky, 1, 2)
+
+	file := path.Join(dir, "a file")
+	verifyFile(t, file, 0222|os.ModeSetuid, 0, 0)
+
+	fis, err := ioutil.ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(fis) != 2 {
+		t.Fatal("Unexpected files in base image")
+	}
+
+}
+
+func DriverTestCreateBase(t *testing.T, drivername string) {
+	driver := GetDriver(t, drivername)
+	defer PutDriver(t)
+
+	createBase(t, driver, "Base")
+	verifyBase(t, driver, "Base")
+
+	if err := driver.Remove("Base"); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func DriverTestCreateSnap(t *testing.T, drivername string) {
+	driver := GetDriver(t, drivername)
+	defer PutDriver(t)
+
+	createBase(t, driver, "Base")
+
+	if err := driver.Create("Snap", "Base"); err != nil {
+		t.Fatal(err)
+	}
+
+	verifyBase(t, driver, "Snap")
+
+	if err := driver.Remove("Snap"); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := driver.Remove("Base"); err != nil {
+		t.Fatal(err)
+	}
+}

daemon/graphdriver/vfs/vfs_test.go

@@ -0,0 +1,28 @@
+package vfs
+
+import (
+	"github.com/dotcloud/docker/daemon/graphdriver/graphtest"
+	"testing"
+)
+
+// This avoids creating a new driver for each test if all tests are run
+// Make sure to put new tests between TestVfsSetup and TestVfsTeardown
+func TestVfsSetup(t *testing.T) {
+	graphtest.GetDriver(t, "vfs")
+}
+
+func TestVfsCreateEmpty(t *testing.T) {
+	graphtest.DriverTestCreateEmpty(t, "vfs")
+}
+
+func TestVfsCreateBase(t *testing.T) {
+	graphtest.DriverTestCreateBase(t, "vfs")
+}
+
+func TestVfsCreateSnap(t *testing.T) {
+	graphtest.DriverTestCreateSnap(t, "vfs")
+}
+
+func TestVfsTeardown(t *testing.T) {
+	graphtest.PutDriver(t)
+}