add rclone

db_test.go

@@ -156,6 +156,23 @@ func TestImplementations(t *testing.T) {
 		t.Log("$MINIO not set. Skipping")
 	}
 
+	f, err := ioutil.TempFile(os.TempDir(), "rclone.conf.*")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(f.Name())
+	f.Write([]byte(`
+[local]
+type = local
+   `))
+	f.Close()
+	rclone, err := NewRClone(f.Name(), "local:/tmp")
+	if err != nil {
+		t.Errorf("cannot make rclone: %v", err)
+	} else {
+		cases = append(cases, rclone)
+	}
+
 	validKey := "key"
 	validValue := []byte("value")
 

rclone.go

@@ -0,0 +1,118 @@
+package storage
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"path"
+	"time"
+
+	"github.com/ncw/rclone/fs"
+	"github.com/ncw/rclone/fs/config"
+	"github.com/ncw/rclone/fs/object"
+
+	_ "github.com/ncw/rclone/backend/drive"
+	_ "github.com/ncw/rclone/backend/local"
+	_ "github.com/ncw/rclone/backend/s3"
+)
+
+type RClone struct {
+	ns string
+}
+
+func NewRClone(rclone string, ns ...string) (*RClone, error) {
+	namespace := path.Join(ns...)
+	_, err := os.Stat(rclone)
+	if err == nil {
+		os.Setenv("RCLONE_CONFIG", rclone)
+		config.ConfigPath = rclone
+		config.LoadConfig()
+	}
+	return &RClone{
+		ns: namespace,
+	}, err
+}
+
+func (rc *RClone) Get(key string, ns ...string) ([]byte, error) {
+	namespace := resolveNamespace(ns)
+	namespace = path.Join(rc.ns, namespace)
+	key = path.Join(namespace, key)
+	f, err := fs.NewFs(path.Dir(key))
+	if err != nil {
+		return nil, err
+	}
+	obj, err := f.NewObject(path.Base(key))
+	if err != nil {
+		return nil, err
+	}
+	r, err := obj.Open()
+	if err != nil {
+		return nil, err
+	}
+	return ioutil.ReadAll(r)
+}
+
+func (rc *RClone) Set(key string, value []byte, ns ...string) error {
+	if len(value) == 0 {
+		return rc.Del(key, ns...)
+	}
+	namespace := resolveNamespace(ns)
+	namespace = path.Join(rc.ns, namespace)
+	key = path.Join(namespace, key)
+	f, err := fs.NewFs(path.Dir(key))
+	if err != nil {
+		return err
+	}
+	obj := object.NewStaticObjectInfo(path.Base(key), time.Now(), 0, true, nil, f)
+	_, err = f.Put(bytes.NewReader(value), obj)
+	return err
+}
+
+func (rc *RClone) Del(key string, ns ...string) error {
+	namespace := resolveNamespace(ns)
+	namespace = path.Join(rc.ns, namespace)
+	key = path.Join(namespace, key)
+	f, err := fs.NewFs(path.Dir(key))
+	if err != nil {
+		return err
+	}
+	obj, err := f.NewObject(path.Base(key))
+	if err == fs.ErrorObjectNotFound {
+		return nil
+	}
+	if err != nil {
+		return nil
+	}
+	return obj.Remove()
+}
+
+func (rc *RClone) Close() error {
+	return nil
+}
+
+func (rc *RClone) List(ns []string, limits ...string) ([]string, error) {
+	namespace := path.Join(resolveNamespace(ns))
+	namespace = path.Join(rc.ns, namespace)
+	limits = resolveLimits(limits)
+
+	f, err := fs.NewFs(namespace)
+	if err != nil {
+		return nil, err
+	}
+	entries, err := f.List("")
+	if err != nil {
+		return nil, err
+	}
+	names := make([]string, 0)
+	for _, entry := range entries {
+		name := entry.Remote()
+		if rc.inRange(name, limits[0], limits[1]) {
+			names = append(names, name)
+		}
+	}
+	return names, nil
+}
+
+func (rc *RClone) inRange(k, start, stop string) bool {
+	return k != "" && k >= start && k <= stop
+}