init

database/kv/pebble.go

@@ -0,0 +1,66 @@
+package kv
+
+import (
+	"github.com/cockroachdb/pebble"
+)
+
+var Impl *KvImpl
+
+type KvImpl struct {
+	PebbleDB *pebble.DB
+}
+
+func NewPebble(datadir string) *KvImpl {
+	db, err := pebble.Open(datadir, &pebble.Options{})
+	if err != nil {
+		panic(err)
+	}
+	return &KvImpl{
+		PebbleDB: db,
+	}
+}
+
+func (db *KvImpl) PebbleSet(key, val string) error {
+	return db.PebbleDB.Set([]byte(key), []byte(val), pebble.Sync)
+}
+
+func (db *KvImpl) PebbleGet(key string) ([]byte, error) {
+	value, _, err := db.PebbleDB.Get([]byte(key))
+	if err != nil {
+		return nil, err
+	}
+
+	return value, nil
+}
+
+func (db *KvImpl) PebbleFetch(prefixKey string) (result map[string]string, err error) {
+	keyUpperBound := func(b []byte) []byte {
+		end := make([]byte, len(b))
+		copy(end, b)
+		for i := len(end) - 1; i >= 0; i-- {
+			end[i] = end[i] + 1
+			if end[i] != 0 {
+				return end[:i+1]
+			}
+		}
+		return nil // no upper-bound
+	}
+
+	prefixIterOptions := func(prefix []byte) *pebble.IterOptions {
+		return &pebble.IterOptions{
+			LowerBound: prefix,
+			UpperBound: keyUpperBound(prefix),
+		}
+	}
+
+	iter, err := db.PebbleDB.NewIter(prefixIterOptions([]byte(prefixKey)))
+
+	if err != nil {
+		return nil, err
+	}
+
+	for iter.First(); iter.Valid(); iter.Next() {
+		result[string(iter.Key())] = string(iter.Value())
+	}
+	return
+}