tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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ManifestMessagesChild.sys.mjs (3229B)

      1 /* This Source Code Form is subject to the terms of the Mozilla Public
      2 * License, v. 2.0. If a copy of the MPL was not distributed with this
      3 * file, You can obtain one at http://mozilla.org/MPL/2.0/.*/
      4 /*
      5 * Manifest obtainer frame script implementation of:
      6 * http://www.w3.org/TR/appmanifest/#obtaining
      7 *
      8 * It searches a top-level browsing context for
      9 * a <link rel=manifest> element. Then fetches
     10 * and processes the linked manifest.
     11 *
     12 * BUG: https://bugzilla.mozilla.org/show_bug.cgi?id=1083410
     13 */
     14 
     15 const lazy = {};
     16 
     17 ChromeUtils.defineESModuleGetters(lazy, {
     18  ManifestFinder: "resource://gre/modules/ManifestFinder.sys.mjs",
     19  ManifestIcons: "resource://gre/modules/ManifestIcons.sys.mjs",
     20  ManifestObtainer: "resource://gre/modules/ManifestObtainer.sys.mjs",
     21 });
     22 
     23 export class ManifestMessagesChild extends JSWindowActorChild {
     24  receiveMessage(message) {
     25    switch (message.name) {
     26      case "DOM:WebManifest:hasManifestLink":
     27        return this.hasManifestLink();
     28      case "DOM:ManifestObtainer:Obtain":
     29        return this.obtainManifest(message.data);
     30      case "DOM:WebManifest:fetchIcon":
     31        return this.fetchIcon(message);
     32    }
     33    return undefined;
     34  }
     35 
     36  /**
     37   * Check if the document includes a link to a web manifest.
     38   */
     39  hasManifestLink() {
     40    const response = makeMsgResponse();
     41    response.result = lazy.ManifestFinder.contentHasManifestLink(
     42      this.contentWindow
     43    );
     44    response.success = true;
     45    return response;
     46  }
     47 
     48  /**
     49   * Asynchronously obtains a web manifest from this window by using the
     50   * ManifestObtainer and returns the result.
     51   *
     52   * @param {object} checkConformance True if spec conformance messages should be collected.
     53   */
     54  async obtainManifest(options) {
     55    const { checkConformance } = options;
     56    const response = makeMsgResponse();
     57    try {
     58      response.result = await lazy.ManifestObtainer.contentObtainManifest(
     59        this.contentWindow,
     60        { checkConformance }
     61      );
     62      response.success = true;
     63    } catch (err) {
     64      response.result = serializeError(err);
     65    }
     66    return response;
     67  }
     68 
     69  /**
     70   * Given a manifest and an expected icon size, ask ManifestIcons
     71   * to fetch the appropriate icon and send along result
     72   */
     73  async fetchIcon({ data: { manifest, iconSize } }) {
     74    const response = makeMsgResponse();
     75    try {
     76      response.result = await lazy.ManifestIcons.contentFetchIcon(
     77        this.contentWindow,
     78        manifest,
     79        iconSize
     80      );
     81      response.success = true;
     82    } catch (err) {
     83      response.result = serializeError(err);
     84    }
     85    return response;
     86  }
     87 }
     88 
     89 /**
     90 * Utility function to Serializes an JS Error, so it can be transferred over
     91 * the message channel.
     92 * FIX ME: https://bugzilla.mozilla.org/show_bug.cgi?id=1172586
     93 *
     94 * @param  {Error} aError The error to serialize.
     95 * @return {object} The serialized object.
     96 */
     97 function serializeError(aError) {
     98  const clone = {
     99    fileName: aError.fileName,
    100    lineNumber: aError.lineNumber,
    101    columnNumber: aError.columnNumber,
    102    stack: aError.stack,
    103    message: aError.message,
    104    name: aError.name,
    105  };
    106  return clone;
    107 }
    108 
    109 function makeMsgResponse() {
    110  return {
    111    success: false,
    112    result: undefined,
    113  };
    114 }