refactor: storage interface

pkg/storage/fs/fs.go

@@ -1,30 +1,75 @@
 // fs implements galaxy/storage.Storage with filesystem
 package fs
 
+/*
+
+Общие правила:
+
+1. Все хранимые объекты сериализуются / десериализуются как JSON.
+
+2. Структура хранения файлов:
+
+- storageRoot \
+			  |
+			  +-- state.dat
+			  |
+			  +-- {GameID} \
+			  |	           |
+			  |			   +-- {Turn}.dat (client.GameData)
+			  |			   +-- {Turn}.dat (client.GameData)
+			  |			   +-- ...
+			  |
+			  +-- {GameID} \
+			  			   |
+						   +-- ...
+
+*/
+
 import (
 	"fmt"
 	"galaxy/util"
+	"path/filepath"
 )
 
-type fsStorage struct {
-	path string
+const (
+	// Name of the file under the storage's root where [model.State] is stored.
+	stateFileName = "state.dat"
+
+	// Suffix of a Game's file inder the storage's root where [model.GameData] is stored.
+	gameDataFileSuffix = ".dat"
+)
+
+// StateFilePath returns client's state file path relative to the root,
+// file name and extension are pre-defined constant.
+func StateFilePath(root string) string {
+	return filepath.Join(root, stateFileName)
 }
 
-// NewFS returns on-filesystem implementation of the "galaxy/storage.Storage" with root located at rootPath.
-// rootPath must me a directory and has write access to the current user. If initial checks failed, return nil and non-nil error.
-func NewStorage(path string) (*fsStorage, error) {
-	if ok, err := util.PathExists(path, true); err != nil {
-		return nil, fmt.Errorf("new storage: check path %q exists: %w", path, err)
+// GameDataPath returns game's data file path relative to the root,
+// data file name is GameID string representation and extension is a pre-defined constant.
+func GameDataFilePath(root string, id fmt.Stringer) string {
+	return filepath.Join(root, id.String()) + gameDataFileSuffix
+}
+
+type fsStorage struct {
+	storageRoot string
+}
+
+// NewFS returns on-filesystem implementation of the "galaxy/storage.Storage" with root located at storageRoot.
+// storageRoot must me a directory and has write access to the current user. If initial checks failed, return nil and non-nil error.
+func NewStorage(storageRoot string) (*fsStorage, error) {
+	if ok, err := util.PathExists(storageRoot, true); err != nil {
+		return nil, fmt.Errorf("new storage: check path %q exists: %w", storageRoot, err)
 	} else if !ok {
-		return nil, fmt.Errorf("new storage: path %q does not exists", path)
+		return nil, fmt.Errorf("new storage: path %q does not exists", storageRoot)
 	}
-	if ok, err := util.Writable(path); err != nil {
-		return nil, fmt.Errorf("new storage: check path %q writable: %w", path, err)
+	if ok, err := util.Writable(storageRoot); err != nil {
+		return nil, fmt.Errorf("new storage: check path %q writable: %w", storageRoot, err)
 	} else if !ok {
-		return nil, fmt.Errorf("new storage: path %q is not writable", path)
+		return nil, fmt.Errorf("new storage: path %q is not writable", storageRoot)
 	}
 	s := &fsStorage{
-		path: path,
+		storageRoot: storageRoot,
 	}
 	return s, nil
 }

pkg/storage/storage.go

@@ -37,16 +37,16 @@ type UIStorage interface {
 	// otherwise callback func accepts loaded [report.Report].
 	LoadReport(client.GameID, uint, func(report.Report, error))
 
-	// PutReport stores given [report.Report] for a given [model.GameID] and turn number at the filesystem asynchronously.
+	// SaveReport stores given [report.Report] for a given [model.GameID] and turn number at the filesystem asynchronously.
 	// I/O or encoding error may occur, it that case callback func will be called with non-nil error.
-	PutReport(client.GameID, uint, report.Report, func(error))
+	SaveReport(client.GameID, uint, report.Report, func(error))
 
 	// LoadOrder loads a [order.Order] for a given [model.GameID] and turn number from filesystem asynchronously.
 	// Passed callback func will will accept non-nil error in case of I/O or decoding errors occuried,
 	// otherwise callback func accepts loaded [order.Order].
 	LoadOrder(client.GameID, uint, func(order.Order, error))
 
-	// PutOrder stores given [order.Order] for a given [model.GameID] and turn number at the filesystem asynchronously.
+	// SaveOrder stores given [order.Order] for a given [model.GameID] and turn number at the filesystem asynchronously.
 	// I/O or encoding error may occur, it that case callback func will be called with non-nil error.
-	PutOrder(client.GameID, uint, order.Order, func(error))
+	SaveOrder(client.GameID, uint, order.Order, func(error))
 }