arangodb adapter

.gitignore

@@ -75,6 +75,8 @@ com_crashlytics_export_strings.xml
 crashlytics.properties
 crashlytics-build.properties
 
+workspace/
+
 test_data
 build
 target

go.mod

@@ -42,7 +42,7 @@ require (
 	github.com/go-stack/stack v1.8.0 // indirect
 	github.com/go-zookeeper/zk v1.0.2 // indirect
 	github.com/gocql/gocql v0.0.0-20210707082121-9a3953d1826d
-	github.com/golang-jwt/jwt v3.2.1+incompatible
+	github.com/golang-jwt/jwt v3.2.2+incompatible
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.2
 	github.com/golang/snappy v0.0.4 // indirect
@@ -169,6 +169,8 @@ require (
 require (
 	cloud.google.com/go/kms v1.0.0 // indirect
 	github.com/DataDog/zstd v1.3.6-0.20190409195224-796139022798 // indirect
+	github.com/arangodb/go-driver v1.2.1 // indirect
+	github.com/arangodb/go-velocypack v0.0.0-20200318135517-5af53c29c67e // indirect
 	github.com/d4l3k/messagediff v1.2.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/jcmturner/aescts/v2 v2.0.0 // indirect

go.sum

@@ -124,6 +124,10 @@ github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d/go.mod h1:rBZYJk5
 github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
 github.com/apache/thrift v0.12.0/go.mod h1:cp2SuWMxlEZw2r+iP2GNCdIi4C1qmUzdZFSVb+bacwQ=
 github.com/apache/thrift v0.13.0/go.mod h1:cp2SuWMxlEZw2r+iP2GNCdIi4C1qmUzdZFSVb+bacwQ=
+github.com/arangodb/go-driver v1.2.1 h1:HREDHhDmzdIWxHmfkfTESbYUnRjESjPh4WUuXq7FZa8=
+github.com/arangodb/go-driver v1.2.1/go.mod h1:zdDkJJnCj8DAkfbtIjIXnsTrWIiy6VhP3Vy14p+uQeY=
+github.com/arangodb/go-velocypack v0.0.0-20200318135517-5af53c29c67e h1:Xg+hGrY2LcQBbxd0ZFdbGSyRKTYMZCfBbw/pMJFOk1g=
+github.com/arangodb/go-velocypack v0.0.0-20200318135517-5af53c29c67e/go.mod h1:mq7Shfa/CaixoDxiyAAc5jZ6CVBAyPaNQCGS7mkj4Ho=
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da/go.mod h1:Q73ZrmVTwzkszR9V5SSuryQ31EELlFMUz1kKyl939pY=
@@ -176,6 +180,7 @@ github.com/colinmarc/hdfs/v2 v2.2.0 h1:4AaIlTq+/sWmeqYhI0dX8bD4YrMQM990tRjm636Fk
 github.com/colinmarc/hdfs/v2 v2.2.0/go.mod h1:Wss6n3mtaZyRwWaqtSH+6ge01qT0rw9dJJmvoUnIQ/E=
 github.com/coreos/bbolt v1.3.2/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE559Wcmn+qkEiiKk=
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
+github.com/coreos/go-iptables v0.4.3/go.mod h1:/mVI274lEDI2ns62jHCDnCyBF9Iwsmekav8Dbxlm1MU=
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
@@ -193,6 +198,7 @@ github.com/d4l3k/messagediff v1.2.1/go.mod h1:Oozbb1TVXFac9FtSIxHBMnBCq2qeH/2KkE
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dchest/uniuri v0.0.0-20160212164326-8902c56451e9/go.mod h1:GgB8SF9nRG+GqaDtLcwJZsQFhcogVCJ79j4EdT0c2V4=
 github.com/devigned/tab v0.1.1/go.mod h1:XG9mPq0dFghrYvoBF3xdRrJzSTX1b7IQrvaL9mzjeJY=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
@@ -290,6 +296,8 @@ github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
 github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
 github.com/golang-jwt/jwt v3.2.1+incompatible h1:73Z+4BJcrTC+KczS6WvTPvRGOp1WmfEP4Q1lOd9Z/+c=
 github.com/golang-jwt/jwt v3.2.1+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
+github.com/golang-jwt/jwt v3.2.2+incompatible h1:IfV12K8xAKAnZqdXVzCZ+TOjboZ2keLg81eXfW3O+oY=
+github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/groupcache v0.0.0-20160516000752-02826c3e7903/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/groupcache v0.0.0-20190129154638-5b532d6fd5ef/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
@@ -690,6 +698,8 @@ github.com/remyoudompheng/bigfft v0.0.0-20200410134404-eec4a21b6bb0/go.mod h1:qq
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
 github.com/rogpeppe/fastuuid v1.2.0/go.mod h1:jVj6XXZzXRy/MSR5jhDC/2q6DgLz+nrA6LYCDYWNEvQ=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
+github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
+github.com/rs/zerolog v1.19.0/go.mod h1:IzD0RJ65iWH0w97OQQebJEvTZYvsCUm9WVLWBQrJRjo=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ryanuber/columnize v0.0.0-20160712163229-9b3edd62028f/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/samuel/go-zookeeper v0.0.0-20190923202752-2cc03de413da/go.mod h1:gi+0XIa01GRL2eRQVjQkKGqKF3SF9vZR/HnPullcV2E=
@@ -1092,6 +1102,7 @@ golang.org/x/tools v0.0.0-20190606124116-d0a3d012864b/go.mod h1:/rFqwRUd4F7ZHNgw
 golang.org/x/tools v0.0.0-20190621195816-6e04913cbbac/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190628153133-6cdbf07be9d0/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190816200558-6889da9d5479/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20190828213141-aed303cbaa74/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20190911174233-4f2ddba30aff/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191012152004-8de300cfc20a/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191029041327-9cc4af7d6b2c/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=

weed/command/imports.go

@@ -15,6 +15,7 @@ import (
 	_ "github.com/chrislusf/seaweedfs/weed/replication/sink/localsink"
 	_ "github.com/chrislusf/seaweedfs/weed/replication/sink/s3sink"
 
+	_ "github.com/chrislusf/seaweedfs/weed/filer/arangodb"
 	_ "github.com/chrislusf/seaweedfs/weed/filer/cassandra"
 	_ "github.com/chrislusf/seaweedfs/weed/filer/elastic/v7"
 	_ "github.com/chrislusf/seaweedfs/weed/filer/etcd"

weed/command/scaffold/filer.toml

@@ -285,6 +285,12 @@ healthcheck_enabled = false
 index.max_result_window = 10000
 
 
+[arangodb] # in development dont use it
+enabled = false
+arango_host=["http://localhost:8529"]
+arango_user=""
+arango_pass=""
+
 
 ##########################
 ##########################

weed/filer/arangodb/arangodb_store.go

@@ -0,0 +1,348 @@
+package arangodb
+
+import (
+	"context"
+	"crypto/md5"
+	"crypto/tls"
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/arangodb/go-driver"
+	"github.com/arangodb/go-driver/http"
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+func init() {
+	filer.Stores = append(filer.Stores, &ArangodbStore{})
+}
+
+type ArangodbStore struct {
+	connect    driver.Connection
+	client     driver.Client
+	database   driver.Database
+	collection driver.Collection
+}
+
+type Model struct {
+	Key       string   `json:"_key"`
+	Directory string   `json:"directory"`
+	Name      string   `json:"name"`
+	Meta      []uint64 `json:"meta"`
+}
+
+func (store *ArangodbStore) GetName() string {
+	return "arangodb"
+}
+
+func (store *ArangodbStore) Initialize(configuration util.Configuration, prefix string) (err error) {
+	return store.connection(configuration.GetStringSlice(prefix+"arango_host"),
+		configuration.GetString(prefix+"arango_user"),
+		configuration.GetString(prefix+"arango_pass"),
+	)
+}
+
+func (store *ArangodbStore) connection(uris []string, user string, pass string) (err error) {
+	ctx, _ := context.WithTimeout(context.Background(), 10*time.Second)
+
+	store.connect, err = http.NewConnection(http.ConnectionConfig{
+		Endpoints: uris,
+		TLSConfig: &tls.Config{
+			InsecureSkipVerify: true,
+		},
+	})
+	if err != nil {
+		return err
+	}
+	store.client, err = driver.NewClient(driver.ClientConfig{
+		Connection:     store.connect,
+		Authentication: driver.BasicAuthentication(user, pass),
+	})
+	if err != nil {
+		return err
+	}
+	db_name := "seaweed-filer"
+	ok, err := store.client.DatabaseExists(ctx, db_name)
+	if err != nil {
+		return err
+	}
+	if ok {
+		store.database, err = store.client.Database(ctx, db_name)
+	} else {
+		store.database, err = store.client.CreateDatabase(ctx, db_name, &driver.CreateDatabaseOptions{})
+	}
+	if err != nil {
+		return err
+	}
+
+	coll_name := "files"
+	ok, err = store.database.CollectionExists(ctx, coll_name)
+	if err != nil {
+		return err
+	}
+	if ok {
+		store.collection, err = store.database.Collection(ctx, coll_name)
+	} else {
+		store.collection, err = store.database.CreateCollection(ctx, coll_name, &driver.CreateCollectionOptions{})
+	}
+	if err != nil {
+		return err
+	}
+
+	// ensure indices
+
+	if _, _, err = store.collection.EnsurePersistentIndex(ctx, []string{"directory", "name"}, &driver.EnsurePersistentIndexOptions{
+		Name:   "directory_name_multi",
+		Unique: true,
+	}); err != nil {
+		return err
+	}
+	if _, _, err = store.collection.EnsurePersistentIndex(ctx, []string{"directory"},
+		&driver.EnsurePersistentIndexOptions{Name: "IDX_directory"}); err != nil {
+		return err
+	}
+
+	if _, _, err = store.collection.EnsureFullTextIndex(ctx, []string{"directory_fulltext"},
+		&driver.EnsureFullTextIndexOptions{Name: "IDX_FULLTEXT_directory", MinLength: 1}); err != nil {
+		return err
+	}
+
+	if _, _, err = store.collection.EnsurePersistentIndex(ctx, []string{"name"}, &driver.EnsurePersistentIndexOptions{
+		Name: "IDX_name",
+	}); err != nil {
+		return err
+	}
+
+	return err
+}
+
+type key int
+
+const (
+	transactionKey key = 0
+)
+
+func (store *ArangodbStore) BeginTransaction(ctx context.Context) (context.Context, error) {
+	txn, err := store.database.BeginTransaction(ctx, driver.TransactionCollections{
+		Exclusive: []string{"files"},
+	}, &driver.BeginTransactionOptions{})
+	if err != nil {
+		return nil, err
+	}
+
+	return context.WithValue(ctx, transactionKey, txn), nil
+}
+
+func (store *ArangodbStore) CommitTransaction(ctx context.Context) error {
+	val := ctx.Value(transactionKey)
+	cast, ok := val.(driver.TransactionID)
+	if !ok {
+		return fmt.Errorf("txn cast fail %s:", val)
+	}
+	err := store.database.CommitTransaction(ctx, cast, &driver.CommitTransactionOptions{})
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (store *ArangodbStore) RollbackTransaction(ctx context.Context) error {
+	val := ctx.Value(transactionKey)
+	cast, ok := val.(driver.TransactionID)
+	if !ok {
+		return fmt.Errorf("txn cast fail %s:", val)
+	}
+	err := store.database.AbortTransaction(ctx, cast, &driver.AbortTransactionOptions{})
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (store *ArangodbStore) InsertEntry(ctx context.Context, entry *filer.Entry) (err error) {
+	dir, name := entry.FullPath.DirAndName()
+	meta, err := entry.EncodeAttributesAndChunks()
+	if err != nil {
+		return fmt.Errorf("encode %s: %s", entry.FullPath, err)
+	}
+
+	if len(entry.Chunks) > 50 {
+		meta = util.MaybeGzipData(meta)
+	}
+	model := &Model{
+		Key:       hashString(string(entry.FullPath)),
+		Directory: dir,
+		Name:      name,
+		Meta:      bytesToArray(meta),
+	}
+	_, err = store.collection.CreateDocument(ctx, model)
+
+	if err != nil {
+		return fmt.Errorf("UpdateEntry %s: %v", entry.FullPath, err)
+	}
+
+	return nil
+
+}
+
+func (store *ArangodbStore) UpdateEntry(ctx context.Context, entry *filer.Entry) (err error) {
+	dir, name := entry.FullPath.DirAndName()
+	meta, err := entry.EncodeAttributesAndChunks()
+	if err != nil {
+		return fmt.Errorf("encode %s: %s", entry.FullPath, err)
+	}
+
+	if len(entry.Chunks) > 50 {
+		meta = util.MaybeGzipData(meta)
+	}
+	model := &Model{
+		Key:       hashString(string(entry.FullPath)),
+		Directory: dir,
+		Name:      name,
+		Meta:      bytesToArray(meta),
+	}
+
+	_, err = store.collection.UpdateDocument(ctx, model.Key, model)
+
+	if err != nil {
+		return fmt.Errorf("UpdateEntry %s: %v", entry.FullPath, err)
+	}
+
+	return nil
+}
+
+func (store *ArangodbStore) FindEntry(ctx context.Context, fullpath util.FullPath) (entry *filer.Entry, err error) {
+	var data Model
+	_, err = store.collection.ReadDocument(ctx, hashString(string(fullpath)), &data)
+	if driver.IsNotFound(err) {
+		return nil, filer_pb.ErrNotFound
+	}
+	if err != nil {
+		glog.Errorf("find %s: %v", fullpath, err)
+		return nil, filer_pb.ErrNotFound
+	}
+	if len(data.Meta) == 0 {
+		return nil, filer_pb.ErrNotFound
+	}
+	entry = &filer.Entry{
+		FullPath: fullpath,
+	}
+	err = entry.DecodeAttributesAndChunks(util.MaybeDecompressData(arrayToBytes(data.Meta)))
+	if err != nil {
+		return entry, fmt.Errorf("decode %s : %v", entry.FullPath, err)
+	}
+
+	return entry, nil
+}
+
+func (store *ArangodbStore) DeleteEntry(ctx context.Context, fullpath util.FullPath) error {
+	_, err := store.collection.RemoveDocument(ctx, hashString(string(fullpath)))
+	if err != nil {
+		glog.Errorf("find %s: %v", fullpath, err)
+		return fmt.Errorf("delete %s : %v", fullpath, err)
+	}
+
+	return nil
+}
+
+func (store *ArangodbStore) DeleteFolderChildren(ctx context.Context, fullpath util.FullPath) error {
+	dir, _ := fullpath.DirAndName()
+	cur, err := store.database.Query(ctx, `
+for d in files
+filter d.directory == @dir
+remove d in files`, map[string]interface{}{"dir": dir})
+	if err != nil {
+		return fmt.Errorf("delete %s : %v", fullpath, err)
+	}
+	defer cur.Close()
+	return nil
+}
+
+func (store *ArangodbStore) ListDirectoryPrefixedEntries(ctx context.Context, dirPath util.FullPath, startFileName string, includeStartFile bool, limit int64, prefix string, eachEntryFunc filer.ListEachEntryFunc) (lastFileName string, err error) {
+	return lastFileName, filer.ErrUnsupportedListDirectoryPrefixed
+}
+
+func (store *ArangodbStore) ListDirectoryEntries(ctx context.Context, dirPath util.FullPath, startFileName string, includeStartFile bool, limit int64, eachEntryFunc filer.ListEachEntryFunc) (lastFileName string, err error) {
+	dir, name := dirPath.DirAndName()
+	eq := ""
+	if includeStartFile {
+		eq = "="
+	}
+	_ = eq
+	_ = name
+
+	cur, err := store.database.Query(ctx, fmt.Sprintf(`
+for d in files
+filter d.directory == @dir
+sort d.name desc
+limit %d
+return d`, limit), map[string]interface{}{
+		"dir": dir,
+	})
+	if err != nil {
+		return lastFileName, fmt.Errorf("failed to list directory entries: find error: %w", err)
+	}
+	defer cur.Close()
+	for cur.HasMore() {
+		var data Model
+		_, err = cur.ReadDocument(ctx, &data)
+		if err != nil {
+			break
+		}
+		entry := &filer.Entry{
+			FullPath: util.NewFullPath(string(dirPath), data.Name),
+		}
+		lastFileName = data.Name
+		converted := arrayToBytes(data.Meta)
+		if decodeErr := entry.DecodeAttributesAndChunks(util.MaybeDecompressData(converted)); decodeErr != nil {
+			err = decodeErr
+			glog.V(0).Infof("list %s : %v", entry.FullPath, err)
+			break
+		}
+
+		if !eachEntryFunc(entry) {
+			break
+		}
+
+	}
+	return lastFileName, err
+}
+
+func (store *ArangodbStore) Shutdown() {
+}
+
+func hashString(dir string) string {
+	h := md5.New()
+	io.WriteString(h, dir)
+	b := h.Sum(nil)
+	return hex.EncodeToString(b)
+}
+
+func bytesToArray(bs []byte) []uint64 {
+	out := make([]uint64, 0, 2+len(bs)/8)
+	out = append(out, uint64(len(bs)))
+	for len(bs)%8 != 0 {
+		bs = append(bs, 0)
+	}
+	for i := 0; i < len(bs); i = i + 8 {
+		out = append(out, binary.BigEndian.Uint64(bs[i:]))
+	}
+	return out
+}
+
+func arrayToBytes(xs []uint64) []byte {
+	if len(xs) < 2 {
+		return []byte{}
+	}
+	first := xs[0]
+	out := make([]byte, len(xs)*8)
+	for i := 1; i < len(xs); i = i + 1 {
+		binary.BigEndian.PutUint64(out[((i-1)*8):], xs[i])
+	}
+	return out[:first]
+}

weed/filer/arangodb/arangodb_store_kv.go

@@ -0,0 +1,62 @@
+package arangodb
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+)
+
+func (store *ArangodbStore) KvPut(ctx context.Context, key []byte, value []byte) (err error) {
+	dir, name := genDirAndName(key)
+	model := &Model{
+		Key:       hashString(string(key)),
+		Directory: dir,
+		Name:      name,
+		Meta:      bytesToArray(value),
+	}
+
+	exists, err := store.collection.DocumentExists(ctx, model.Key)
+	if err != nil {
+		return fmt.Errorf("kv put: %v", err)
+	}
+	if exists {
+		_, err = store.collection.UpdateDocument(ctx, model.Key, model)
+	} else {
+		_, err = store.collection.CreateDocument(ctx, model)
+	}
+	if err != nil {
+		return fmt.Errorf("kv put: %v", err)
+	}
+
+	return nil
+}
+
+func (store *ArangodbStore) KvGet(ctx context.Context, key []byte) (value []byte, err error) {
+	var model Model
+	_, err = store.collection.ReadDocument(ctx, hashString(string(key)), &model)
+	if err != nil {
+		glog.Errorf("kv get: %v", err)
+		return nil, filer.ErrKvNotFound
+	}
+	return arrayToBytes(model.Meta), nil
+}
+
+func (store *ArangodbStore) KvDelete(ctx context.Context, key []byte) (err error) {
+	_, err = store.collection.RemoveDocument(ctx, hashString(string(key)))
+	if err != nil {
+		glog.Errorf("kv del: %v", err)
+		return filer.ErrKvNotFound
+	}
+	return nil
+}
+
+func genDirAndName(key []byte) (dir string, name string) {
+	for len(key) < 8 {
+		key = append(key, 0)
+	}
+	dir = string(key[:8])
+	name = string(key[8:])
+	return
+}

weed/server/filer_server.go

@@ -21,6 +21,7 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/util"
 
 	"github.com/chrislusf/seaweedfs/weed/filer"
+	_ "github.com/chrislusf/seaweedfs/weed/filer/arangodb"
 	_ "github.com/chrislusf/seaweedfs/weed/filer/cassandra"
 	_ "github.com/chrislusf/seaweedfs/weed/filer/elastic/v7"
 	_ "github.com/chrislusf/seaweedfs/weed/filer/etcd"