Add a LevelDB database

model/database.go

@@ -0,0 +1,90 @@
+package reveil
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"math/rand"
+
+	"github.com/syndtr/goleveldb/leveldb"
+	"github.com/syndtr/goleveldb/leveldb/errors"
+	"github.com/syndtr/goleveldb/leveldb/iterator"
+	"github.com/syndtr/goleveldb/leveldb/util"
+)
+
+type LevelDBStorage struct {
+	db *leveldb.DB
+}
+
+// NewMySQLStorage establishes the connection to the database
+func NewLevelDBStorage(path string) (s *LevelDBStorage, err error) {
+	var db *leveldb.DB
+
+	db, err = leveldb.OpenFile(path, nil)
+	if err != nil {
+		if _, ok := err.(*errors.ErrCorrupted); ok {
+			log.Println("LevelDB was corrupted; attempting recovery (%s)", err.Error())
+			_, err = leveldb.RecoverFile(path, nil)
+			if err != nil {
+				return
+			}
+			log.Println("LevelDB recovery succeeded!")
+		} else {
+			return
+		}
+	}
+
+	s = &LevelDBStorage{db}
+	return
+}
+
+func (s *LevelDBStorage) Close() error {
+	return s.db.Close()
+}
+
+func decodeData(data []byte, v interface{}) error {
+	return json.Unmarshal(data, v)
+}
+
+func (s *LevelDBStorage) get(key string, v interface{}) error {
+	data, err := s.db.Get([]byte(key), nil)
+	if err != nil {
+		return err
+	}
+
+	return decodeData(data, v)
+}
+
+func (s *LevelDBStorage) put(key string, v interface{}) error {
+	data, err := json.Marshal(v)
+	if err != nil {
+		return err
+	}
+
+	return s.db.Put([]byte(key), data, nil)
+}
+
+func (s *LevelDBStorage) findBytesKey(prefix string, len int) (key string, id Identifier, err error) {
+	id = make([]byte, len)
+	found := true
+	for found {
+		if _, err = rand.Read(id); err != nil {
+			return
+		}
+		key = fmt.Sprintf("%s%s", prefix, id.ToString())
+
+		found, err = s.db.Has([]byte(key), nil)
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+func (s *LevelDBStorage) delete(key string) error {
+	return s.db.Delete([]byte(key), nil)
+}
+
+func (s *LevelDBStorage) search(prefix string) iterator.Iterator {
+	return s.db.NewIterator(util.BytesPrefix([]byte(prefix)), nil)
+}