55 lines
1.5 KiB
JavaScript
55 lines
1.5 KiB
JavaScript
/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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'use strict';
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module.metadata = {
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'stability': 'experimental'
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};
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let { request: hostReq, response: hostRes } = require('./host');
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let { defer: async } = require('../lang/functional');
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let { defer } = require('../core/promise');
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let { emit: emitSync, on, off } = require('../event/core');
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let { uuid } = require('../util/uuid');
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let emit = async(emitSync);
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// Map of IDs to deferreds
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let requests = new Map();
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// May not be necessary to wrap this in `async`
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// once promises are async via bug 881047
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let receive = async(function ({data, id, error}) {
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let request = requests.get(id);
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if (request) {
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if (error) request.reject(error);
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else request.resolve(clone(data));
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requests.delete(id);
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}
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});
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on(hostRes, 'data', receive);
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/*
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* Send is a helper to be used in client APIs to send
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* a request to host
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*/
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function send (eventName, data) {
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let id = uuid();
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let deferred = defer();
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requests.set(id, deferred);
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emit(hostReq, 'data', {
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id: id,
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data: clone(data),
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event: eventName
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});
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return deferred.promise;
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}
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exports.send = send;
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/*
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* Implement internal structured cloning algorithm in the future?
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* http://www.whatwg.org/specs/web-apps/current-work/multipage/common-dom-interfaces.html#internal-structured-cloning-algorithm
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*/
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function clone (obj) JSON.parse(JSON.stringify(obj || {}))
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