gecko-dev/dom/ipc/ManifestMessagesChild.jsm

128 строки
4.2 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.*/
/*
* Manifest obtainer frame script implementation of:
* http://www.w3.org/TR/appmanifest/#obtaining
*
* It searches a top-level browsing context for
* a <link rel=manifest> element. Then fetches
* and processes the linked manifest.
*
* BUG: https://bugzilla.mozilla.org/show_bug.cgi?id=1083410
*/
"use strict";
var EXPORTED_SYMBOLS = ["ManifestMessagesChild"];
ChromeUtils.import("resource://gre/modules/ActorChild.jsm");
ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm");
ChromeUtils.defineModuleGetter(this, "ManifestObtainer",
"resource://gre/modules/ManifestObtainer.jsm");
ChromeUtils.defineModuleGetter(this, "ManifestFinder",
"resource://gre/modules/ManifestFinder.jsm");
ChromeUtils.defineModuleGetter(this, "ManifestIcons",
"resource://gre/modules/ManifestIcons.jsm");
class ManifestMessagesChild extends ActorChild {
receiveMessage(message) {
switch (message.name) {
case "DOM:WebManifest:hasManifestLink":
return this.hasManifestLink(message);
case "DOM:ManifestObtainer:Obtain":
return this.obtainManifest(message);
case "DOM:Manifest:FireAppInstalledEvent":
return this.fireAppInstalledEvent(message);
case "DOM:WebManifest:fetchIcon":
return this.fetchIcon(message);
}
return undefined;
}
/**
* Check if the this.mm.content document includes a link to a web manifest.
* @param {Object} aMsg The IPC message, which is destructured to just
* get the id.
*/
hasManifestLink({data: {id}}) {
const response = makeMsgResponse(id);
response.result = ManifestFinder.contentHasManifestLink(this.mm.content);
response.success = true;
this.mm.sendAsyncMessage("DOM:WebManifest:hasManifestLink", response);
}
/**
* Asynchronously obtains a web manifest from this.mm.content by using the
* ManifestObtainer and messages back the result.
* @param {Object} aMsg The IPC message, which is destructured to just
* get the id.
*/
async obtainManifest({data: {id}}) {
const response = makeMsgResponse(id);
try {
response.result = await ManifestObtainer.contentObtainManifest(this.mm.content);
response.success = true;
} catch (err) {
response.result = serializeError(err);
}
this.mm.sendAsyncMessage("DOM:ManifestObtainer:Obtain", response);
}
fireAppInstalledEvent({data: {id}}) {
const ev = new Event("appinstalled");
const response = makeMsgResponse(id);
if (!this.mm.content || this.mm.content.top !== this.mm.content) {
const msg = "Can only dispatch install event on top-level browsing contexts.";
response.result = serializeError(new Error(msg));
} else {
response.success = true;
this.mm.content.dispatchEvent(ev);
}
this.mm.sendAsyncMessage("DOM:Manifest:FireAppInstalledEvent", response);
}
/**
* Given a manifest and an expected icon size, ask ManifestIcons
* to fetch the appropriate icon and send along result
*/
async fetchIcon({data: {id, manifest, iconSize}}) {
const response = makeMsgResponse(id);
try {
response.result =
await ManifestIcons.contentFetchIcon(this.mm.content, manifest, iconSize);
response.success = true;
} catch (err) {
response.result = serializeError(err);
}
this.mm.sendAsyncMessage("DOM:WebManifest:fetchIcon", response);
}
}
/**
* Utility function to Serializes an JS Error, so it can be transferred over
* the message channel.
* FIX ME: https://bugzilla.mozilla.org/show_bug.cgi?id=1172586
* @param {Error} aError The error to serialize.
* @return {Object} The serialized object.
*/
function serializeError(aError) {
const clone = {
"fileName": aError.fileName,
"lineNumber": aError.lineNumber,
"columnNumber": aError.columnNumber,
"stack": aError.stack,
"message": aError.message,
"name": aError.name
};
return clone;
}
function makeMsgResponse(aId) {
return {
id: aId,
success: false,
result: undefined
};
}