sdk: setup KVStore.

sdk/kvstore/memory/store.go

@@ -0,0 +1,58 @@
+package memory
+
+import (
+	"sync"
+
+	"github.com/nbd-wtf/go-nostr/sdk/kvstore"
+)
+
+var _ kvstore.KVStore = (*Store)(nil)
+
+type Store struct {
+	sync.RWMutex
+	data map[string][]byte
+}
+
+func NewStore() *Store {
+	return &Store{
+		data: make(map[string][]byte),
+	}
+}
+
+func (s *Store) Get(key []byte) ([]byte, error) {
+	s.RLock()
+	defer s.RUnlock()
+	
+	if val, ok := s.data[string(key)]; ok {
+		// Return a copy to prevent modification of stored data
+		cp := make([]byte, len(val))
+		copy(cp, val)
+		return cp, nil
+	}
+	return nil, nil
+}
+
+func (s *Store) Set(key []byte, value []byte) error {
+	s.Lock()
+	defer s.Unlock()
+	
+	// Store a copy to prevent modification of stored data
+	cp := make([]byte, len(value))
+	copy(cp, value)
+	s.data[string(key)] = cp
+	return nil
+}
+
+func (s *Store) Delete(key []byte) error {
+	s.Lock()
+	defer s.Unlock()
+	delete(s.data, string(key))
+	return nil
+}
+
+func (s *Store) Close() error {
+	s.Lock()
+	defer s.Unlock()
+	s.data = nil
+	return nil
+}