Merge remote-tracking branch 'wmhilton/window.fetch'

package.json

@@ -23,7 +23,7 @@
     "node": ">= 0.10"
   },
   "bin": {
-    "make_xhrfs_index": "./dist/scripts/make_xhrfs_index.js"
+    "make_http_index": "./dist/scripts/make_http_index.js"
   },
   "devDependencies": {
     "@types/archiver": "^2.0.0",
@@ -32,6 +32,7 @@
     "@types/express": "^4.0.36",
     "@types/filesystem": "0.0.28",
     "@types/mocha": "^2.2.41",
+    "@types/isomorphic-fetch": "^0.0.34",
     "@types/node": "~7.0",
     "@types/rimraf": "~0.0.28",
     "archiver": "^2.0.0",
@@ -100,9 +101,9 @@
     "script:make_fixture_loader": "node build/scripts/make_fixture_loader.js",
     "script:make_test_launcher": "node build/scripts/make_test_launcher.js",
     "script:make_zip_fixtures": "node build/scripts/make_zip_fixtures",
-    "script:make_xhrfs_index": "node build/scripts/make_xhrfs_index.js test/fixtures/xhrfs/listings.json",
+    "script:make_http_index": "node build/scripts/make_http_index.js test/fixtures/xhrfs/listings.json",
     "test:karma": "karma start karma.config.js",
-    "test:prepare": "npm-run-all build:scripts script:make_fixture_loader script:make_test_launcher test:build script:make_zip_fixtures script:make_xhrfs_index",
+    "test:prepare": "npm-run-all build:scripts script:make_fixture_loader script:make_test_launcher test:build script:make_zip_fixtures script:make_http_index",
     "test": "npm-run-all test:prepare test:karma",
     "watch-test": "npm-run-all test:prepare --parallel watch:scripts test:watch test:karma",
     "prepublish": "npm run dist",

src/backend/XmlHttpRequest.ts

@@ -5,7 +5,8 @@ import {copyingSlice} from '../core/util';
 import {File} from '../core/file';
 import Stats from '../core/node_fs_stats';
 import {NoSyncFile} from '../generic/preload_file';
-import {asyncDownloadFile, syncDownloadFile, getFileSizeAsync, getFileSizeSync} from '../generic/xhr';
+import {xhrIsAvailable, asyncDownloadFile, syncDownloadFile, getFileSizeAsync, getFileSizeSync} from '../generic/xhr';
+import {fetchIsAvailable, fetchFileAsync, fetchFileSizeAsync} from '../generic/fetch';
 import {FileIndex, isFileInode, isDirInode} from '../generic/file_index';
 
 /**
@@ -26,23 +27,42 @@ function tryToString(buff: Buffer, encoding: string, cb: BFSCallback<string>) {
  * Configuration options for an XmlHttpRequest file system.
  */
 export interface XmlHttpRequestOptions {
-  // URL to a file index as a JSON file or the file index object itself, generated with the make_xhrfs_index script.
+  // URL to a file index as a JSON file or the file index object itself, generated with the make_http_index script.
   // Defaults to `index.json`.
   index?: string | object;
   // Used as the URL prefix for fetched files.
   // Default: Fetch files relative to the index.
   baseUrl?: string;
+  // Whether to prefer XmlHttpRequest or fetch for async operations if both are available.
+  // Default: false
+  preferXHR?: boolean;
+}
+
+interface AsyncDownloadFileMethod {
+  (p: string, type: 'buffer', cb: BFSCallback<Buffer>): void;
+  (p: string, type: 'json', cb: BFSCallback<any>): void;
+  (p: string, type: string, cb: BFSCallback<any>): void;
+}
+
+interface SyncDownloadFileMethod {
+  (p: string, type: 'buffer'): Buffer;
+  (p: string, type: 'json'): any;
+  (p: string, type: string): any;
+}
+
+function syncNotAvailableError(): never {
+  throw new ApiError(ErrorCode.ENOTSUP, `Synchronous HTTP download methods are not available in this environment.`);
 }
 
 /**
- * A simple filesystem backed by XMLHttpRequests. You must create a directory listing using the
- * `make_xhrfs_index` tool provided by BrowserFS.
+ * A simple filesystem backed by HTTP downloads. You must create a directory listing using the
+ * `make_http_index` tool provided by BrowserFS.
  *
  * If you install BrowserFS globally with `npm i -g browserfs`, you can generate a listing by
- * running `make_xhrfs_index` in your terminal in the directory you would like to index:
+ * running `make_http_index` in your terminal in the directory you would like to index:
  *
  * ```
- * make_xhrfs_index > index.json
+ * make_http_index > index.json
  * ```
  *
  * Listings objects look like the following:
@@ -69,12 +89,17 @@ export default class XmlHttpRequest extends BaseFileSystem implements FileSystem
     index: {
       type: ["string", "object"],
       optional: true,
-      description: "URL to a file index as a JSON file or the file index object itself, generated with the make_xhrfs_index script. Defaults to `index.json`."
+      description: "URL to a file index as a JSON file or the file index object itself, generated with the make_http_index script. Defaults to `index.json`."
     },
     baseUrl: {
       type: "string",
       optional: true,
       description: "Used as the URL prefix for fetched files. Default: Fetch files relative to the index."
+    },
+    preferXHR: {
+      type: "boolean",
+      optional: true,
+      description: "Whether to prefer XmlHttpRequest or fetch for async operations if both are available. Default: false"
     }
   };
 
@@ -97,21 +122,42 @@ export default class XmlHttpRequest extends BaseFileSystem implements FileSystem
       cb(null, new XmlHttpRequest(opts.index, opts.baseUrl));
     }
   }
+
   public static isAvailable(): boolean {
-    return typeof(XMLHttpRequest) !== "undefined" && XMLHttpRequest !== null;
+    return xhrIsAvailable || fetchIsAvailable;
   }
 
   public readonly prefixUrl: string;
   private _index: FileIndex<{}>;
+  private _requestFileAsyncInternal: AsyncDownloadFileMethod;
+  private _requestFileSizeAsyncInternal: (p: string, cb: BFSCallback<number>) => void;
+  private _requestFileSyncInternal: SyncDownloadFileMethod;
+  private _requestFileSizeSyncInternal: (p: string) => number;
 
-  private constructor(index: object, prefixUrl: string = '') {
+  private constructor(index: object, prefixUrl: string = '', preferXHR: boolean = false) {
     super();
     // prefix_url must end in a directory separator.
     if (prefixUrl.length > 0 && prefixUrl.charAt(prefixUrl.length - 1) !== '/') {
       prefixUrl = prefixUrl + '/';
     }
     this.prefixUrl = prefixUrl;
     this._index = FileIndex.fromListing(index);
+
+    if (fetchIsAvailable && (!preferXHR || !xhrIsAvailable)) {
+      this._requestFileAsyncInternal = fetchFileAsync;
+      this._requestFileSizeAsyncInternal = fetchFileSizeAsync;
+    } else {
+      this._requestFileAsyncInternal = asyncDownloadFile;
+      this._requestFileSizeAsyncInternal = getFileSizeAsync;
+    }
+
+    if (xhrIsAvailable) {
+      this._requestFileSyncInternal = syncDownloadFile;
+      this._requestFileSizeSyncInternal = getFileSizeSync;
+    } else {
+      this._requestFileSyncInternal = syncNotAvailableError;
+      this._requestFileSizeSyncInternal = syncNotAvailableError;
+    }
   }
 
   public empty(): void {
@@ -143,11 +189,12 @@ export default class XmlHttpRequest extends BaseFileSystem implements FileSystem
   }
 
   public supportsSynch(): boolean {
-    return true;
+    // Synchronous operations are only available via the XHR interface for now.
+    return xhrIsAvailable;
   }
 
   /**
-   * Special XHR function: Preload the given file into the index.
+   * Special HTTPFS function: Preload the given file into the index.
    * @param [String] path
    * @param [BrowserFS.Buffer] buffer
    */
@@ -358,7 +405,7 @@ export default class XmlHttpRequest extends BaseFileSystem implements FileSystem
     }
   }
 
-  private getXhrPath(filePath: string): string {
+  private _getHTTPPath(filePath: string): string {
     if (filePath.charAt(0) === '/') {
       filePath = filePath.slice(1);
     }
@@ -372,7 +419,7 @@ export default class XmlHttpRequest extends BaseFileSystem implements FileSystem
   private _requestFileAsync(p: string, type: 'json', cb: BFSCallback<any>): void;
   private _requestFileAsync(p: string, type: string, cb: BFSCallback<any>): void;
   private _requestFileAsync(p: string, type: string, cb: BFSCallback<any>): void {
-    asyncDownloadFile(this.getXhrPath(p), type, cb);
+    this._requestFileAsyncInternal(this._getHTTPPath(p), type, cb);
   }
 
   /**
@@ -382,16 +429,17 @@ export default class XmlHttpRequest extends BaseFileSystem implements FileSystem
   private _requestFileSync(p: string, type: 'json'): any;
   private _requestFileSync(p: string, type: string): any;
   private _requestFileSync(p: string, type: string): any {
-    return syncDownloadFile(this.getXhrPath(p), type);
+    return this._requestFileSyncInternal(this._getHTTPPath(p), type);
   }
 
   /**
    * Only requests the HEAD content, for the file size.
    */
   private _requestFileSizeAsync(path: string, cb: BFSCallback<number>): void {
-    getFileSizeAsync(this.getXhrPath(path), cb);
+    this._requestFileSizeAsyncInternal(this._getHTTPPath(path), cb);
   }
+
   private _requestFileSizeSync(path: string): number {
-    return getFileSizeSync(this.getXhrPath(path));
+    return this._requestFileSizeSyncInternal(this._getHTTPPath(path));
   }
 }

src/generic/fetch.ts

@@ -0,0 +1,66 @@
+/**
+ * Contains utility methods using 'fetch'.
+ */
+
+import {ApiError, ErrorCode} from '../core/api_error';
+import {BFSCallback} from '../core/file_system';
+
+export const fetchIsAvailable = (typeof(fetch) !== "undefined" && fetch !== null);
+
+/**
+ * Asynchronously download a file as a buffer or a JSON object.
+ * Note that the third function signature with a non-specialized type is
+ * invalid, but TypeScript requires it when you specialize string arguments to
+ * constants.
+ * @hidden
+ */
+export function fetchFileAsync(p: string, type: 'buffer', cb: BFSCallback<Buffer>): void;
+export function fetchFileAsync(p: string, type: 'json', cb: BFSCallback<any>): void;
+export function fetchFileAsync(p: string, type: string, cb: BFSCallback<any>): void;
+export function fetchFileAsync(p: string, type: string, cb: BFSCallback<any>): void {
+  let request;
+  try {
+    request = fetch(p);
+  } catch (e) {
+    // XXX: fetch will throw a TypeError if the URL has credentials in it
+    return cb(new ApiError(ErrorCode.EINVAL, e.message));
+  }
+  request
+  .then((res) => {
+    if (!res.ok) {
+      return cb(new ApiError(ErrorCode.EIO, `fetch error: response returned code ${res.status}`));
+    } else {
+      switch (type) {
+        case 'buffer':
+          res.arrayBuffer()
+            .then((buf) => cb(null, Buffer.from(buf)))
+            .catch((err) => cb(new ApiError(ErrorCode.EIO, err.message)));
+          break;
+        case 'json':
+          res.json()
+            .then((json) => cb(null, json))
+            .catch((err) => cb(new ApiError(ErrorCode.EIO, err.message)));
+          break;
+        default:
+          cb(new ApiError(ErrorCode.EINVAL, "Invalid download type: " + type));
+      }
+    }
+  })
+  .catch((err) => cb(new ApiError(ErrorCode.EIO, err.message)));
+}
+
+/**
+ * Asynchronously retrieves the size of the given file in bytes.
+ * @hidden
+ */
+export function fetchFileSizeAsync(p: string, cb: BFSCallback<number>): void {
+  fetch(p, { method: 'HEAD' })
+    .then((res) => {
+      if (!res.ok) {
+        return cb(new ApiError(ErrorCode.EIO, `fetch HEAD error: response returned code ${res.status}`));
+      } else {
+        return cb(null, parseInt(res.headers.get('Content-Length') || '-1', 10));
+      }
+    })
+    .catch((err) => cb(new ApiError(ErrorCode.EIO, err.message)));
+}

src/generic/xhr.ts

@@ -7,6 +7,8 @@ import {isIE, emptyBuffer} from '../core/util';
 import {ApiError, ErrorCode} from '../core/api_error';
 import {BFSCallback} from '../core/file_system';
 
+export const xhrIsAvailable = (typeof(XMLHttpRequest) !== "undefined" && XMLHttpRequest !== null);
+
 /**
  * @hidden
  */
@@ -50,7 +52,7 @@ function asyncDownloadFileModern(p: string, type: string, cb: BFSCallback<any>):
             }
         }
       } else {
-        return cb(new ApiError(req.status, "XHR error."));
+        return cb(new ApiError(ErrorCode.EIO, `XHR error: response returned code ${req.status}`));
       }
     }
   };
@@ -93,7 +95,7 @@ function syncDownloadFileModern(p: string, type: string): any {
             return;
         }
       } else {
-        err = new ApiError(req.status, "XHR error.");
+        err = new ApiError(ErrorCode.EIO, `XHR error: response returned code ${req.status}`);
         return;
       }
     }
@@ -140,7 +142,7 @@ function syncDownloadFileIE10(p: string, type: string): any {
             break;
         }
       } else {
-        err = new ApiError(req.status, "XHR error.");
+        err = new ApiError(ErrorCode.EIO, `XHR error: response returned code ${req.status}`);
       }
     }
   };
@@ -167,7 +169,7 @@ function getFileSize(async: boolean, p: string, cb: BFSCallback<number>): void {
           return cb(new ApiError(ErrorCode.EIO, "XHR HEAD error: Could not read content-length."));
         }
       } else {
-        return cb(new ApiError(req.status, "XHR HEAD error."));
+        return cb(new ApiError(ErrorCode.EIO, `XHR HEAD error: response returned code ${req.status}`));
       }
     }
   };

test/harness/factories/xhrfs_factory.ts

@@ -5,13 +5,20 @@ export default function XHRFSFactory(cb: (name: string, objs: FileSystem[]) => v
   if (XmlHttpRequestFS.isAvailable()) {
     XmlHttpRequestFS.Create({
       index: 'test/fixtures/xhrfs/listings.json',
-      baseUrl: '../'
-    }, (e, fs) => {
-      if (e) {
-        cb('XmlHttpRequest', []);
-      } else {
-        cb('XmlHttpRequest', [fs]);
-      }
+      baseUrl: '../',
+      preferXHR: true
+    }, (e1, xhrFS) => {
+      XmlHttpRequestFS.Create({
+        index: 'test/fixtures/xhrfs/listings.json',
+        baseUrl: '../',
+        preferXHR: false
+      }, (e2, fetchFS) => {
+        if (e1 || e2) {
+          throw e1 || e2;
+        } else {
+          cb('XmlHttpRequest', [xhrFS, fetchFS]);
+        }
+      });
     });
   } else {
     cb('XmlHttpRequest', []);

yarn.lock

@@ -63,6 +63,10 @@
   version "9.1.9"
   resolved "https://registry.yarnpkg.com/@types/highlight.js/-/highlight.js-9.1.9.tgz#ed6336955eaf233b75eb7923b9b1f373d045ef01"
 
+"@types/isomorphic-fetch@^0.0.34":
+  version "0.0.34"
+  resolved "https://registry.yarnpkg.com/@types/isomorphic-fetch/-/isomorphic-fetch-0.0.34.tgz#3c3483e606c041378438e951464f00e4e60706d6"
+
 "@types/lodash@^4.14.37":
   version "4.14.71"
   resolved "https://registry.yarnpkg.com/@types/lodash/-/lodash-4.14.71.tgz#0dc383f78981216ac76e2f2c3afd998e0450e4c1"