add Cassandra

weed/filer2/cassandra/README.txt

@@ -0,0 +1,12 @@
+1. create a keyspace
+
+CREATE KEYSPACE seaweedfs WITH replication = {'class':'SimpleStrategy', 'replication_factor' : 1};
+
+2. create filemeta table
+
+ CREATE TABLE filemeta (
+    directory varchar,
+    name varchar,
+    meta blob,
+    PRIMARY KEY (directory, name)
+ ) WITH CLUSTERING ORDER BY (name ASC);

weed/filer2/cassandra/cassandra_store.go

@@ -0,0 +1,136 @@
+package cassandra
+
+import (
+	"fmt"
+	"github.com/gocql/gocql"
+	"github.com/chrislusf/seaweedfs/weed/filer2"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/spf13/viper"
+)
+
+func init() {
+	filer2.Stores = append(filer2.Stores, &CassandraStore{})
+}
+
+type CassandraStore struct {
+	cluster *gocql.ClusterConfig
+	session *gocql.Session
+}
+
+func (store *CassandraStore) GetName() string {
+	return "cassandra"
+}
+
+func (store *CassandraStore) Initialize(viper *viper.Viper) (err error) {
+	return store.initialize(
+		viper.GetString("keyspace"),
+		viper.GetStringSlice("hosts"),
+	)
+}
+
+func (store *CassandraStore) initialize(keyspace string, hosts []string) (err error) {
+	store.cluster = gocql.NewCluster(hosts...)
+	store.cluster.Keyspace = keyspace
+	store.cluster.Consistency = gocql.LocalQuorum
+	store.session, err = store.cluster.CreateSession()
+	if err != nil {
+		glog.V(0).Infof("Failed to open cassandra store, hosts %v, keyspace %s", hosts, keyspace)
+	}
+	return
+}
+
+func (store *CassandraStore) InsertEntry(entry *filer2.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 err := store.session.Query(
+		"INSERT INTO filemeta (directory,name,meta) VALUES(?,?,?)",
+		dir, name, meta).Exec(); err != nil {
+		return fmt.Errorf("insert %s: %s", entry.FullPath, err)
+	}
+
+	return nil
+}
+
+func (store *CassandraStore) UpdateEntry(entry *filer2.Entry) (err error) {
+
+	return store.InsertEntry(entry)
+}
+
+func (store *CassandraStore) FindEntry(fullpath filer2.FullPath) (entry *filer2.Entry, err error) {
+
+	dir, name := fullpath.DirAndName()
+	var data []byte
+	if err := store.session.Query(
+		"SELECT meta FROM filemeta WHERE directory=? AND name=?",
+		dir, name).Consistency(gocql.One).Scan(&data); err != nil {
+		if err != gocql.ErrNotFound {
+			return nil, fmt.Errorf("read entry %s: %v", fullpath, err)
+		}
+	}
+
+	if len(data) == 0 {
+		return nil, fmt.Errorf("not found: %s", fullpath)
+	}
+
+	entry = &filer2.Entry{
+		FullPath: fullpath,
+	}
+	err = entry.DecodeAttributesAndChunks(data)
+	if err != nil {
+		return entry, fmt.Errorf("decode %s : %v", entry.FullPath, err)
+	}
+
+	return entry, nil
+}
+
+func (store *CassandraStore) DeleteEntry(fullpath filer2.FullPath) (entry *filer2.Entry, err error) {
+
+	entry, err = store.FindEntry(fullpath)
+	if err != nil {
+		return nil, nil
+	}
+
+	dir, name := fullpath.DirAndName()
+
+	if err := store.session.Query(
+		"DELETE FROM filemeta WHERE directory=? AND name=?",
+		dir, name).Exec(); err != nil {
+		return entry, fmt.Errorf("delete %s : %v", entry.FullPath, err)
+	}
+
+	return entry, nil
+}
+
+func (store *CassandraStore) ListDirectoryEntries(fullpath filer2.FullPath, startFileName string, inclusive bool,
+	limit int) (entries []*filer2.Entry, err error) {
+
+	cqlStr := "SELECT NAME, meta FROM filemeta WHERE directory=? AND name>? ORDER BY NAME ASC LIMIT ?"
+	if inclusive {
+		cqlStr = "SELECT NAME, meta FROM filemeta WHERE directory=? AND name>=? ORDER BY NAME ASC LIMIT ?"
+	}
+
+	var data []byte
+	var name string
+	iter := store.session.Query(cqlStr, string(fullpath), startFileName, limit).Iter()
+	for iter.Scan(&name, &data) {
+		entry := &filer2.Entry{
+			FullPath: filer2.NewFullPath(string(fullpath), name),
+		}
+		if decodeErr := entry.DecodeAttributesAndChunks(data); decodeErr != nil {
+			err = decodeErr
+			glog.V(0).Infof("list %s : %v", entry.FullPath, err)
+			break
+		}
+		entries = append(entries, entry)
+	}
+	if err := iter.Close(); err != nil {
+		glog.V(0).Infof("list iterator close: %v", err)
+	}
+
+	return entries, err
+}

weed/filer2/configuration.go

@@ -61,6 +61,19 @@ sslmode = "disable"
 connection_max_idle = 100
 connection_max_open = 100
 
+[cassandra]
+# CREATE TABLE filemeta (
+#    directory varchar,
+#    name varchar,
+#    meta blob,
+#    PRIMARY KEY (directory, name)
+# ) WITH CLUSTERING ORDER BY (name ASC);
+enabled = false
+keyspace="seaweedfs"
+hosts=[
+	"localhost:9042",
+]
+
 `
 )
 

weed/server/filer_server.go

@@ -12,6 +12,7 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/storage"
 	"github.com/chrislusf/seaweedfs/weed/util"
 	"github.com/chrislusf/seaweedfs/weed/filer2"
+	_ "github.com/chrislusf/seaweedfs/weed/filer2/cassandra"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/leveldb"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/memdb"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/mysql"