Improved directory storage

README.md

@@ -44,6 +44,10 @@ for user := range users.All() {
 
 ## Storage systems
 
+### nil
+
+You can specify `nil` as the storage system which will keep data in RAM only.
+
 ### storage.File
 
 `storage.File` uses a single file to store all records.
@@ -59,6 +63,10 @@ You should use `storage.File` if you have a permanently running process such as
 
 Make sure you `defer collection.Sync()` to ensure that queued writes will be handled when the process ends.
 
+### storage.Directory
+
+`storage.Directory` creates a directory for your records and saves each record in a separate file. The performance of this method heavily depends on the file system you are using.
+
 ## Benchmarks
 
 ```

storage/Directory.go

@@ -20,7 +20,7 @@ func (ds *Directory[T]) Init(c ocean.StorageData) error {
 	ds.directory = filepath.Join(c.Root(), c.Name())
 	err := os.Mkdir(ds.directory, 0700)
 
-	if err != nil {
+	if err != nil && !os.IsExist(err) {
 		return err
 	}
 
@@ -70,8 +70,8 @@ func (ds *Directory[T]) read() error {
 
 // readFile loads a single file from the disk.
 func (ds *Directory[T]) readFile(fileName string) error {
-	fileName = filepath.Join(ds.directory, fileName)
-	file, err := os.Open(fileName)
+	filePath := filepath.Join(ds.directory, fileName)
+	file, err := os.Open(filePath)
 
 	if err != nil {
 		return err

storage/Directory_test.go

@@ -0,0 +1,42 @@
+package storage_test
+
+import (
+	"testing"
+
+	"git.akyoto.dev/go/assert"
+	"git.akyoto.dev/go/ocean"
+	"git.akyoto.dev/go/ocean/storage"
+)
+
+var _ ocean.Storage[string] = (*storage.Directory[string])(nil)
+
+func TestDirectoryPersistence(t *testing.T) {
+	users, err := ocean.New[User]("test", &storage.Directory[User]{})
+	assert.Nil(t, err)
+
+	defer users.Sync()
+	defer users.Clear()
+
+	users.Set("1", &User{Name: "User 1"})
+	users.Set("2", &User{Name: "User 2"})
+	users.Set("3", &User{Name: "User 3"})
+	users.Sync()
+
+	reload, err := ocean.New[User]("test", &storage.Directory[User]{})
+	assert.Nil(t, err)
+
+	user, err := reload.Get("1")
+	assert.Nil(t, err)
+	assert.NotNil(t, user)
+	assert.Equal(t, user.Name, "User 1")
+
+	user, err = reload.Get("2")
+	assert.Nil(t, err)
+	assert.NotNil(t, user)
+	assert.Equal(t, user.Name, "User 2")
+
+	user, err = reload.Get("3")
+	assert.Nil(t, err)
+	assert.NotNil(t, user)
+	assert.Equal(t, user.Name, "User 3")
+}

storage/File_test.go

@@ -8,16 +8,13 @@ import (
 	"git.akyoto.dev/go/ocean/storage"
 )
 
+var _ ocean.Storage[string] = (*storage.File[string])(nil)
+
 type User struct {
 	Name string `json:"name"`
 }
 
-func TestInterface(t *testing.T) {
-	var _ ocean.Storage[string] = (*storage.File[string])(nil)
-	var _ ocean.Storage[string] = (*storage.Directory[string])(nil)
-}
-
-func TestPersistence(t *testing.T) {
+func TestFilePersistence(t *testing.T) {
 	users, err := ocean.New[User]("test", &storage.File[User]{})
 	assert.Nil(t, err)