Updated Storage backend to support all Storages

src/backends/Storage.ts

@@ -0,0 +1,93 @@
+import { SyncKeyValueStore, SimpleSyncStore, SyncKeyValueFileSystem, SimpleSyncRWTransaction, SyncKeyValueRWTransaction } from '../generic/key_value_filesystem';
+import { ApiError, ErrorCode } from '../ApiError';
+import { Buffer } from 'buffer';
+import { CreateBackend, type BackendOptions } from './backend';
+
+/**
+ * A synchronous key-value store backed by Storage.
+ */
+export class StorageStore implements SyncKeyValueStore, SimpleSyncStore {
+	public name(): string {
+		return StorageFileSystem.Name;
+	}
+
+	constructor(protected _storage) {}
+
+	public clear(): void {
+		this._storage.clear();
+	}
+
+	public beginTransaction(type: string): SyncKeyValueRWTransaction {
+		// No need to differentiate.
+		return new SimpleSyncRWTransaction(this);
+	}
+
+	public get(key: string): Buffer | undefined {
+		const data = this._storage.getItem(key);
+		if (typeof data != 'string') {
+			return;
+		}
+
+		return Buffer.from(data);
+	}
+
+	public put(key: string, data: Buffer, overwrite: boolean): boolean {
+		try {
+			if (!overwrite && this._storage.getItem(key) !== null) {
+				// Don't want to overwrite the key!
+				return false;
+			}
+			this._storage.setItem(key, data.toString());
+			return true;
+		} catch (e) {
+			throw new ApiError(ErrorCode.ENOSPC, 'Storage is full.');
+		}
+	}
+
+	public del(key: string): void {
+		try {
+			this._storage.removeItem(key);
+		} catch (e) {
+			throw new ApiError(ErrorCode.EIO, 'Unable to delete key ' + key + ': ' + e);
+		}
+	}
+}
+
+export namespace StorageFileSystem {
+	/**
+	 * Options to pass to the StorageFileSystem
+	 */
+	export interface Options {
+		/**
+		 * The Storage to use. Defaults to globalThis.localStorage.
+		 */
+		storage: Storage;
+	}
+}
+
+/**
+ * A synchronous file system backed by a `Storage` (e.g. localStorage).
+ */
+export class StorageFileSystem extends SyncKeyValueFileSystem {
+	public static readonly Name = 'Storage';
+
+	public static Create = CreateBackend.bind(this);
+
+	public static readonly Options: BackendOptions = {
+		storage: {
+			type: 'object',
+			optional: true,
+			description: 'The Storage to use. Defaults to globalThis.localStorage.',
+		},
+	};
+
+	public static isAvailable(storage: Storage = globalThis.localStorage): boolean {
+		return storage instanceof Storage;
+	}
+	/**
+	 * Creates a new Storage file system using the contents of `Storage`.
+	 */
+	constructor({ storage = globalThis.localStorage }: StorageFileSystem.Options) {
+		super({ store: new StorageStore(storage) });
+	}
+}

src/backends/index.ts

@@ -5,7 +5,7 @@ import { FileSystemAccessFileSystem as FileSystemAccess } from './FileSystemAcce
 import { FolderAdapter } from './FolderAdapter';
 import { InMemoryFileSystem as InMemory } from './InMemory';
 import { IndexedDBFileSystem as IndexedDB } from './IndexedDB';
-import { LocalStorageFileSystem as LocalStorage } from './LocalStorage';
+import { StorageFileSystem as Storage } from './Storage';
 import { OverlayFS } from './OverlayFS';
 import { WorkerFS } from './WorkerFS';
 import { HTTPRequest } from './HTTPRequest';
@@ -22,7 +22,7 @@ export const backends: { [backend: string]: BackendConstructor } = {
 	InMemory,
 	IndexedDB,
 	IsoFS,
-	LocalStorage,
+	Storage,
 	OverlayFS,
 	WorkerFS,
 	HTTPRequest,
@@ -39,7 +39,7 @@ export {
 	InMemory,
 	IndexedDB,
 	IsoFS,
-	LocalStorage,
+	Storage,
 	OverlayFS,
 	WorkerFS,
 	HTTPRequest,

src/index.ts

@@ -99,14 +99,14 @@ export function configure(config: Configuration, cb?: BFSOneArgCallback): Promis
  * Individual options can recursively contain FileSystemConfiguration objects for
  * option values that require file systems.
  *
- * For example, to mirror Dropbox to LocalStorage with AsyncMirror, use the following
+ * For example, to mirror Dropbox to Storage with AsyncMirror, use the following
  * object:
  *
  * ```javascript
  * var config = {
  *   fs: "AsyncMirror",
  *   options: {
- *     sync: {fs: "LocalStorage"},
+ *     sync: {fs: "Storage"},
  *     async: {fs: "Dropbox", options: {client: anAuthenticatedDropboxSDKClient }}
  *   }
  * };

test/common.ts

@@ -42,7 +42,7 @@ const tests /*: { [B in keyof typeof Backends]: Parameters<typeof Backends[B]['C
 	InMemory: {},
 	//IndexedDB: {},
 	//IsoFS: {},
-	//LocalStorage: {},
+	//Storage: {},
 	OverlayFS: { readable: { fs: 'InMemory' }, writable: { fs: 'InMemory' } },
 	//WorkerFS: {},
 	//HTTPRequest: {},