sdk: setup KVStore.

sdk/kvstore/badger/store.go

@@ -0,0 +1,59 @@
+package badger
+
+import (
+	"github.com/dgraph-io/badger/v4"
+	"github.com/nbd-wtf/go-nostr/sdk/kvstore"
+)
+
+var _ kvstore.KVStore = (*Store)(nil)
+
+type Store struct {
+	db *badger.DB
+}
+
+func NewStore(path string) (*Store, error) {
+	opts := badger.DefaultOptions(path)
+	db, err := badger.Open(opts)
+	if err != nil {
+		return nil, err
+	}
+	return &Store{db: db}, nil
+}
+
+func (s *Store) Get(key []byte) ([]byte, error) {
+	var valCopy []byte
+	err := s.db.View(func(txn *badger.Txn) error {
+		item, err := txn.Get(key)
+		if err == badger.ErrKeyNotFound {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+		return item.Value(func(val []byte) error {
+			valCopy = make([]byte, len(val))
+			copy(valCopy, val)
+			return nil
+		})
+	})
+	if err != nil {
+		return nil, err
+	}
+	return valCopy, nil
+}
+
+func (s *Store) Set(key []byte, value []byte) error {
+	return s.db.Update(func(txn *badger.Txn) error {
+		return txn.Set(key, value)
+	})
+}
+
+func (s *Store) Delete(key []byte) error {
+	return s.db.Update(func(txn *badger.Txn) error {
+		return txn.Delete(key)
+	})
+}
+
+func (s *Store) Close() error {
+	return s.db.Close()
+}

sdk/kvstore/interface.go

@@ -0,0 +1,16 @@
+package kvstore
+
+// KVStore is a simple key-value store interface
+type KVStore interface {
+	// Get retrieves a value for a given key. Returns nil if not found.
+	Get(key []byte) ([]byte, error)
+	
+	// Set stores a value for a given key
+	Set(key []byte, value []byte) error
+	
+	// Delete removes a key and its value
+	Delete(key []byte) error
+	
+	// Close releases any resources held by the store
+	Close() error
+}

sdk/kvstore/lmdb/store.go

@@ -0,0 +1,92 @@
+package lmdb
+
+import (
+	"os"
+
+	"github.com/PowerDNS/lmdb-go/lmdb"
+	"github.com/nbd-wtf/go-nostr/sdk/kvstore"
+)
+
+var _ kvstore.KVStore = (*Store)(nil)
+
+type Store struct {
+	env *lmdb.Env
+	dbi lmdb.DBI
+}
+
+func NewStore(path string) (*Store, error) {
+	// create directory if it doesn't exist
+	if err := os.MkdirAll(path, 0755); err != nil {
+		return nil, err
+	}
+
+	// initialize environment
+	env, err := lmdb.NewEnv()
+	if err != nil {
+		return nil, err
+	}
+
+	// set max DBs and map size
+	env.SetMaxDBs(1)
+	env.SetMapSize(1 << 30) // 1GB
+
+	// open the environment
+	if err := env.Open(path, lmdb.NoTLS|lmdb.WriteMap, 0644); err != nil {
+		return nil, err
+	}
+
+	store := &Store{env: env}
+
+	// open the database
+	if err := env.Update(func(txn *lmdb.Txn) error {
+		dbi, err := txn.OpenDBI("store", lmdb.Create)
+		if err != nil {
+			return err
+		}
+		store.dbi = dbi
+		return nil
+	}); err != nil {
+		env.Close()
+		return nil, err
+	}
+
+	return store, nil
+}
+
+func (s *Store) Get(key []byte) ([]byte, error) {
+	var value []byte
+	err := s.env.View(func(txn *lmdb.Txn) error {
+		v, err := txn.Get(s.dbi, key)
+		if lmdb.IsNotFound(err) {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+		// make a copy since v is only valid during the transaction
+		value = make([]byte, len(v))
+		copy(value, v)
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return value, nil
+}
+
+func (s *Store) Set(key []byte, value []byte) error {
+	return s.env.Update(func(txn *lmdb.Txn) error {
+		return txn.Put(s.dbi, key, value, 0)
+	})
+}
+
+func (s *Store) Delete(key []byte) error {
+	return s.env.Update(func(txn *lmdb.Txn) error {
+		return txn.Del(s.dbi, key, nil)
+	})
+}
+
+func (s *Store) Close() error {
+	s.env.Close()
+	return nil
+}

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
+}