seaweedfs/weed/filer/cassandra/cassandra_store.go
2021-01-14 22:38:34 -08:00

215 lines
6.4 KiB
Go

package cassandra
import (
"context"
"fmt"
"github.com/gocql/gocql"
"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, &CassandraStore{})
}
type CassandraStore struct {
cluster *gocql.ClusterConfig
session *gocql.Session
superLargeDirectoryHash map[string]string
}
func (store *CassandraStore) GetName() string {
return "cassandra"
}
func (store *CassandraStore) Initialize(configuration util.Configuration, prefix string) (err error) {
return store.initialize(
configuration.GetString(prefix+"keyspace"),
configuration.GetStringSlice(prefix+"hosts"),
configuration.GetString(prefix+"username"),
configuration.GetString(prefix+"password"),
configuration.GetStringSlice(prefix+"superLargeDirectories"),
)
}
func (store *CassandraStore) isSuperLargeDirectory(dir string) (dirHash string, isSuperLargeDirectory bool) {
dirHash, isSuperLargeDirectory = store.superLargeDirectoryHash[dir]
return
}
func (store *CassandraStore) initialize(keyspace string, hosts []string, username string, password string, superLargeDirectories []string) (err error) {
store.cluster = gocql.NewCluster(hosts...)
if username != "" && password != "" {
store.cluster.Authenticator = gocql.PasswordAuthenticator{Username: username, Password: password}
}
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)
}
// set directory hash
store.superLargeDirectoryHash = make(map[string]string)
existingHash := make(map[string]string)
for _, dir := range superLargeDirectories {
// adding dir hash to avoid duplicated names
dirHash := util.Md5String([]byte(dir))[:4]
store.superLargeDirectoryHash[dir] = dirHash
if existingDir, found := existingHash[dirHash]; found {
glog.Fatalf("directory %s has the same hash as %s", dir, existingDir)
}
existingHash[dirHash] = dir
}
return
}
func (store *CassandraStore) BeginTransaction(ctx context.Context) (context.Context, error) {
return ctx, nil
}
func (store *CassandraStore) CommitTransaction(ctx context.Context) error {
return nil
}
func (store *CassandraStore) RollbackTransaction(ctx context.Context) error {
return nil
}
func (store *CassandraStore) InsertEntry(ctx context.Context, entry *filer.Entry) (err error) {
dir, name := entry.FullPath.DirAndName()
if dirHash, ok := store.isSuperLargeDirectory(dir); ok {
dir, name = dirHash+name, ""
}
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)
}
if err := store.session.Query(
"INSERT INTO filemeta (directory,name,meta) VALUES(?,?,?) USING TTL ? ",
dir, name, meta, entry.TtlSec).Exec(); err != nil {
return fmt.Errorf("insert %s: %s", entry.FullPath, err)
}
return nil
}
func (store *CassandraStore) UpdateEntry(ctx context.Context, entry *filer.Entry) (err error) {
return store.InsertEntry(ctx, entry)
}
func (store *CassandraStore) FindEntry(ctx context.Context, fullpath util.FullPath) (entry *filer.Entry, err error) {
dir, name := fullpath.DirAndName()
if dirHash, ok := store.isSuperLargeDirectory(dir); ok {
dir, name = dirHash+name, ""
}
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, filer_pb.ErrNotFound
}
}
if len(data) == 0 {
return nil, filer_pb.ErrNotFound
}
entry = &filer.Entry{
FullPath: fullpath,
}
err = entry.DecodeAttributesAndChunks(util.MaybeDecompressData(data))
if err != nil {
return entry, fmt.Errorf("decode %s : %v", entry.FullPath, err)
}
return entry, nil
}
func (store *CassandraStore) DeleteEntry(ctx context.Context, fullpath util.FullPath) error {
dir, name := fullpath.DirAndName()
if dirHash, ok := store.isSuperLargeDirectory(dir); ok {
dir, name = dirHash+name, ""
}
if err := store.session.Query(
"DELETE FROM filemeta WHERE directory=? AND name=?",
dir, name).Exec(); err != nil {
return fmt.Errorf("delete %s : %v", fullpath, err)
}
return nil
}
func (store *CassandraStore) DeleteFolderChildren(ctx context.Context, fullpath util.FullPath) error {
if _, ok := store.isSuperLargeDirectory(string(fullpath)); ok {
return nil // filer.ErrUnsupportedSuperLargeDirectoryListing
}
if err := store.session.Query(
"DELETE FROM filemeta WHERE directory=?",
fullpath).Exec(); err != nil {
return fmt.Errorf("delete %s : %v", fullpath, err)
}
return nil
}
func (store *CassandraStore) ListDirectoryPrefixedEntries(ctx context.Context, dirPath util.FullPath, startFileName string, includeStartFile bool, limit int, prefix string) (entries []*filer.Entry, hasMore bool, err error) {
return nil, false, filer.ErrUnsupportedListDirectoryPrefixed
}
func (store *CassandraStore) ListDirectoryEntries(ctx context.Context, dirPath util.FullPath, startFileName string, includeStartFile bool, limit int) (entries []*filer.Entry, hasMore bool, err error) {
if _, ok := store.isSuperLargeDirectory(string(dirPath)); ok {
return // nil, filer.ErrUnsupportedSuperLargeDirectoryListing
}
cqlStr := "SELECT NAME, meta FROM filemeta WHERE directory=? AND name>? ORDER BY NAME ASC LIMIT ?"
if includeStartFile {
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(dirPath), startFileName, limit+1).Iter()
for iter.Scan(&name, &data) {
entry := &filer.Entry{
FullPath: util.NewFullPath(string(dirPath), name),
}
if decodeErr := entry.DecodeAttributesAndChunks(util.MaybeDecompressData(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)
}
hasMore = len(entries) == limit + 1
if hasMore {
entries = entries[:limit]
}
return entries, hasMore, err
}
func (store *CassandraStore) Shutdown() {
store.session.Close()
}