Some minor API updates.

archive/decompress.js

@@ -0,0 +1,84 @@
+/**
+ * decompress.js
+ *
+ * Provides base functionality for unarchiving/decompression.
+ *
+ * Licensed under the MIT License
+ *
+ * Copyright(c) 2021 Google Inc.
+ */
+
+ import { UnarchiveAppendEvent, UnarchiveErrorEvent, UnarchiveEvent, UnarchiveEventType,
+  UnarchiveExtractEvent, UnarchiveFinishEvent, UnarchiveInfoEvent,
+  UnarchiveProgressEvent, UnarchiveStartEvent, Unarchiver,
+  UnrarrerInternal, UntarrerInternal, UnzipperInternal,
+  getUnarchiverInternal } from './decompress-internal.js';
+
+export {
+  UnarchiveAppendEvent,
+  UnarchiveErrorEvent,
+  UnarchiveEvent,
+  UnarchiveEventType,
+  UnarchiveExtractEvent,
+  UnarchiveFinishEvent,
+  UnarchiveInfoEvent,
+  UnarchiveProgressEvent,
+  UnarchiveStartEvent,
+  Unarchiver,
+} 
+
+/**
+* All extracted files returned by an Unarchiver will implement
+* the following interface:
+*/
+
+/**
+* @typedef UnarchivedFile
+* @property {string} filename
+* @property {Uint8Array} fileData
+*/
+
+/**
+* The goal is to make this testable - send getUnarchiver() an array buffer of
+* an archive, call start on the unarchiver, expect the returned result.
+*
+* Problem: It relies on Web Workers, and that won't work in a nodejs context.
+* Solution: Make archive.js very thin, have it feed web-specific things into
+*           an internal module that is isomorphic JavaScript.
+*
+* TODO:
+* - write unit tests for archive-internal.js that use the nodejs Worker
+*   equivalent.
+* - maybe use @pgriess/node-webworker or @audreyt/node-webworker-threads or
+*   just node's worker_threads ?
+*/
+
+const createWorkerFn = (scriptFilename) => new Worker(scriptFilename);
+
+// Thin wrappers of compressors for clients who want to construct a specific
+// unarchiver themselves rather than use getUnarchiver().
+export class Unzipper extends UnzipperInternal {
+  constructor(ab, options) { super(ab, createWorkerFn, options); }
+}
+
+export class Unrarrer extends UnrarrerInternal {
+  constructor(ab, options) { super(ab, createWorkerFn, options); }
+}
+
+export class Untarrer extends UntarrerInternal {
+  constructor(ab, options) { super(ab, createWorkerFn, options); }
+}
+
+/**
+* Factory method that creates an unarchiver based on the byte signature found
+* in the arrayBuffer.
+* @param {ArrayBuffer} ab The ArrayBuffer to unarchive. Note that this ArrayBuffer
+*     must not be referenced after calling this method, as the ArrayBuffer is marked
+*     as Transferable and sent to a Worker thread once start() is called.
+* @param {Object|string} options An optional object of options, or a string
+*     representing where the path to the unarchiver script files.
+* @return {Unarchiver}
+*/
+export function getUnarchiver(ab, options = {}) {
+  return getUnarchiverInternal(ab, createWorkerFn, options);
+}