@aws-amplify/core
Version:
Core category of aws-amplify
184 lines • 6.63 kB
JavaScript
;
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
Object.defineProperty(exports, "__esModule", { value: true });
var tslib_1 = require("tslib");
var Logger_1 = require("./Logger");
var logger = new Logger_1.ConsoleLogger('Hub');
var AMPLIFY_SYMBOL = (typeof Symbol !== 'undefined' && typeof Symbol.for === 'function'
? Symbol.for('amplify_default')
: '@@amplify_default');
function isLegacyCallback(callback) {
return callback.onHubCapsule !== undefined;
}
var HubClass = /** @class */ (function () {
function HubClass(name) {
this.listeners = [];
this.patterns = [];
this.protectedChannels = [
'core',
'auth',
'api',
'analytics',
'interactions',
'pubsub',
'storage',
'ui',
'xr',
];
this.name = name;
}
/**
* Used internally to remove a Hub listener.
*
* @remarks
* This private method is for internal use only. Instead of calling Hub.remove, call the result of Hub.listen.
*/
HubClass.prototype._remove = function (channel, listener) {
if (channel instanceof RegExp) {
var pattern_1 = this.patterns.find(function (_a) {
var pattern = _a.pattern;
return pattern.source === channel.source;
});
if (!pattern_1) {
logger.warn("No listeners for " + channel);
return;
}
this.patterns = tslib_1.__spread(this.patterns.filter(function (x) { return x !== pattern_1; }));
}
else {
var holder = this.listeners[channel];
if (!holder) {
logger.warn("No listeners for " + channel);
return;
}
this.listeners[channel] = tslib_1.__spread(holder.filter(function (_a) {
var callback = _a.callback;
return callback !== listener;
}));
}
};
/**
* @deprecated Instead of calling Hub.remove, call the result of Hub.listen.
*/
HubClass.prototype.remove = function (channel, listener) {
this._remove(channel, listener);
};
/**
* Used to send a Hub event.
*
* @param channel - The channel on which the event will be broadcast
* @param payload - The HubPayload
* @param source - The source of the event; defaults to ''
* @param ampSymbol - Symbol used to determine if the event is dispatched internally on a protected channel
*
*/
HubClass.prototype.dispatch = function (channel, payload, source, ampSymbol) {
if (source === void 0) { source = ''; }
if (this.protectedChannels.indexOf(channel) > -1) {
var hasAccess = ampSymbol === AMPLIFY_SYMBOL;
if (!hasAccess) {
logger.warn("WARNING: " + channel + " is protected and dispatching on it can have unintended consequences");
}
}
var capsule = {
channel: channel,
payload: tslib_1.__assign({}, payload),
source: source,
patternInfo: [],
};
try {
this._toListeners(capsule);
}
catch (e) {
logger.error(e);
}
};
/**
* Used to listen for Hub events.
*
* @param channel - The channel on which to listen
* @param callback - The callback to execute when an event is received on the specified channel
* @param listenerName - The name of the listener; defaults to 'noname'
* @returns A function which can be called to cancel the listener.
*
*/
HubClass.prototype.listen = function (channel, callback, listenerName) {
var _this = this;
if (listenerName === void 0) { listenerName = 'noname'; }
var cb;
// Check for legacy onHubCapsule callback for backwards compatability
if (isLegacyCallback(callback)) {
logger.warn("WARNING onHubCapsule is Deprecated. Please pass in a callback.");
cb = callback.onHubCapsule.bind(callback);
}
else if (typeof callback !== 'function') {
throw new Error('No callback supplied to Hub');
}
else {
cb = callback;
}
if (channel instanceof RegExp) {
this.patterns.push({
pattern: channel,
callback: cb,
});
}
else {
var holder = this.listeners[channel];
if (!holder) {
holder = [];
this.listeners[channel] = holder;
}
holder.push({
name: listenerName,
callback: cb,
});
}
return function () {
_this._remove(channel, cb);
};
};
HubClass.prototype._toListeners = function (capsule) {
var channel = capsule.channel, payload = capsule.payload;
var holder = this.listeners[channel];
if (holder) {
holder.forEach(function (listener) {
logger.debug("Dispatching to " + channel + " with ", payload);
try {
listener.callback(capsule);
}
catch (e) {
logger.error(e);
}
});
}
if (this.patterns.length > 0) {
if (!payload.message) {
logger.warn("Cannot perform pattern matching without a message key");
return;
}
var payloadStr_1 = payload.message;
this.patterns.forEach(function (pattern) {
var match = payloadStr_1.match(pattern.pattern);
if (match) {
var _a = tslib_1.__read(match), groups = _a.slice(1);
var dispatchingCapsule = tslib_1.__assign(tslib_1.__assign({}, capsule), { patternInfo: groups });
try {
pattern.callback(dispatchingCapsule);
}
catch (e) {
logger.error(e);
}
}
});
}
};
return HubClass;
}());
exports.HubClass = HubClass;
/*We export a __default__ instance of HubClass to use it as a
pseudo Singleton for the main messaging bus, however you can still create
your own instance of HubClass() for a separate "private bus" of events.*/
exports.Hub = new HubClass('__default__');
//# sourceMappingURL=Hub.js.map