h5p-php-library/js/request-queue.js

451 lines
12 KiB
JavaScript

/**
* Queue requests and handle them at your convenience
*
* @type {RequestQueue}
*/
H5P.RequestQueue = (function ($, EventDispatcher) {
/**
* A queue for requests, will be automatically processed when regaining connection
*
* @param {boolean} [options.showToast] Show toast when losing or regaining connection
* @constructor
*/
const RequestQueue = function (options) {
EventDispatcher.call(this);
this.processingQueue = false;
options = options || {};
this.showToast = options.showToast;
this.itemName = 'requestQueue';
// Initialize listener for when requests are added to queue
window.addEventListener('offline', this.updateOnlineStatus.bind(this));
window.addEventListener('online', this.updateOnlineStatus.bind(this));
this.on('connectionReestablished', function () {
this.resumeQueue();
}.bind(this));
};
/**
* Add request to queue. Only supports posts currently.
*
* @param {string} url
* @param {Object} data
* @returns {boolean}
*/
RequestQueue.prototype.add = function (url, data) {
if (!window.localStorage) {
return false;
}
let storedStatements = this.getStoredRequests();
if (!storedStatements) {
storedStatements = [];
}
storedStatements.push({
url: url,
data: data,
});
window.localStorage.setItem(this.itemName, JSON.stringify(storedStatements));
this.trigger('requestQueued', {
storedStatements: storedStatements,
processingQueue: this.processingQueue,
});
return true;
};
/**
* Get stored requests
*
* @returns {boolean|Array} Stored requests
*/
RequestQueue.prototype.getStoredRequests = function () {
if (!window.localStorage) {
return false;
}
const item = window.localStorage.getItem(this.itemName);
if (!item) {
return [];
}
return JSON.parse(item);
};
/**
* Clear stored requests
*
* @returns {boolean} True if the storage was successfully cleared
*/
RequestQueue.prototype.clearQueue = function () {
if (!window.localStorage) {
return false;
}
window.localStorage.removeItem(this.itemName);
return true;
};
/**
* Start processing of requests queue
*
* @return {boolean} Returns false if it was not possible to resume processing queue
*/
RequestQueue.prototype.resumeQueue = function () {
// Not supported
if (!H5PIntegration || !window.navigator || !window.localStorage) {
return false;
}
// Already processing
if (this.processingQueue) {
return false;
}
// Attempt to send queued requests
const queue = this.getStoredRequests();
const queueLength = queue.length;
// Clear storage, failed requests will be re-added
this.clearQueue();
// No items left in queue
if (!queueLength) {
this.trigger('emptiedQueue', queue);
return true;
}
// Make sure requests are not changed while they're being handled
this.processingQueue = true;
// Process queue in original order
this.processQueue(queue);
return true
};
/**
* Process first item in the request queue
*
* @param {Array} queue Request queue
*/
RequestQueue.prototype.processQueue = function (queue) {
if (!queue.length) {
return;
}
this.trigger('processingQueue');
// Make sure the requests are processed in a FIFO order
const request = queue.shift();
const self = this;
$.post(request.url, request.data)
.fail(self.onQueuedRequestFail.bind(self, request))
.always(self.onQueuedRequestProcessed.bind(self, queue))
};
/**
* Request fail handler
*
* @param {Object} request
*/
RequestQueue.prototype.onQueuedRequestFail = function (request) {
// Queue the failed request again if we're offline
if (!window.navigator.onLine) {
this.add(request.url, request.data);
}
};
/**
* An item in the queue was processed
*
* @param {Array} queue Queue that was processed
*/
RequestQueue.prototype.onQueuedRequestProcessed = function (queue) {
if (queue.length) {
this.processQueue(queue);
return;
}
// Finished processing this queue
this.processingQueue = false;
// Run empty queue callback with next request queue
const requestQueue = this.getStoredRequests();
this.trigger('queueEmptied', requestQueue);
};
/**
* Display toast message on the first content of current page
*
* @param {string} msg Message to display
* @param {boolean} [forceShow] Force override showing the toast
*/
RequestQueue.prototype.displayToastMessage = function (msg, forceShow) {
if (!this.showToast && !forceShow) {
return;
}
H5P.attachToastTo(
H5P.jQuery('.h5p-content:first')[0],
msg,
{
position: {
horizontal: 'centered',
vertical: 'centered',
noOverflowX: true
}
}
);
};
/**
* Update online status
*/
RequestQueue.prototype.updateOnlineStatus = function () {
// Lost connection
if (!window.navigator.onLine) {
this.displayToastMessage(H5P.t('connectionLost'));
return;
}
// Re-connected, resume processing of queue
let message = H5P.t('connectionReestablished');
const requestQueue = this.getStoredRequests();
if (requestQueue.length) {
message += ' ' + H5P.t('resubmitScores');
this.trigger('connectionReestablished');
}
this.displayToastMessage(message);
};
return RequestQueue;
})(H5P.jQuery, H5P.EventDispatcher);
/**
* Request queue for retrying failing requests, will automatically retry them when you come online
*
* @type {offlineRequestQueue}
*/
H5P.OfflineRequestQueue = (function (RequestQueue, Dialog) {
/**
* Constructor
*
* @param {Object} [options] Options for offline request queue
* @param {Object} [options.instance] The H5P instance which UI components are placed within
*/
const offlineRequestQueue = function (options) {
const requestQueue = new RequestQueue();
// We could handle requests from previous pages here, but instead we throw them away
requestQueue.clearQueue();
let startTime = null;
const retryIntervals = [10, 20, 40, 60, 120, 300, 600];
let intervalIndex = -1;
let currentInterval = null;
let isAttached = false;
let isShowing = false;
let isLoading = false;
const instance = options.instance;
const offlineDialog = new Dialog({
headerText: H5P.t('offlineDialogHeader'),
dialogText: H5P.t('offlineDialogBody'),
confirmText: H5P.t('offlineDialogRetryButtonLabel'),
hideCancel: true,
hideExit: true,
classes: ['offline'],
instance: instance,
});
const dialog = offlineDialog.getElement();
// Add retry text to body
const countDownText = document.createElement('div');
countDownText.classList.add('count-down');
countDownText.innerHTML = H5P.t('offlineDialogRetryMessage')
.replace(':num', '<span class="count-down-num">0</span>');
dialog.querySelector('.h5p-confirmation-dialog-text').appendChild(countDownText);
const countDownNum = countDownText.querySelector('.count-down-num');
// Create throbber
const throbberWrapper = document.createElement('div');
throbberWrapper.classList.add('throbber-wrapper');
const throbber = document.createElement('div');
throbber.classList.add('sending-requests-throbber');
throbberWrapper.appendChild(throbber);
requestQueue.on('requestQueued', function (e) {
// Already processing queue, wait until queue has finished processing before showing dialog
if (e.data && e.data.processingQueue) {
return;
}
if (!isAttached) {
const rootContent = document.body.querySelector('.h5p-content');
if (!rootContent) {
return;
}
offlineDialog.appendTo(rootContent);
rootContent.appendChild(throbberWrapper);
isAttached = true;
}
startCountDown();
}.bind(this));
requestQueue.on('queueEmptied', function (e) {
if (e.data && e.data.length) {
// New requests were added while processing queue or requests failed again. Re-queue requests.
startCountDown(true);
return;
}
// Successfully emptied queue
clearInterval(currentInterval);
toggleThrobber(false);
intervalIndex = -1;
if (isShowing) {
offlineDialog.hide();
isShowing = false;
}
requestQueue.displayToastMessage(H5P.t('offlineSuccessfulSubmit'), true);
}.bind(this));
requestQueue.on('connectionReestablished', function () {
// Skip resuming queue since request queue already does this
retryRequests(true);
}.bind(this));
offlineDialog.on('confirmed', function () {
// Show dialog on next render in case it is being hidden by the 'confirm' button
isShowing = false;
setTimeout(function () {
retryRequests();
}, 100);
}.bind(this));
// Listen for queued requests outside the iframe
window.addEventListener('message', function (event) {
const isValidQueueEvent = window.parent === event.source
&& event.data.context === 'h5p'
&& event.data.action === 'queueRequest';
if (!isValidQueueEvent) {
return;
}
this.add(event.data.url, event.data.data);
}.bind(this));
/**
* Toggle throbber visibility
*
* @param {boolean} [forceShow] Will force throbber visibility if set
*/
const toggleThrobber = function (forceShow) {
isLoading = !isLoading;
if (forceShow !== undefined) {
isLoading = forceShow;
}
if (isLoading && isShowing) {
offlineDialog.hide();
isShowing = false;
}
if (isLoading) {
throbberWrapper.classList.add('show');
} else {
throbberWrapper.classList.remove('show');
}
};
/**
* Retries the failed requests
*
* @param {boolean} [skipResumeQueue] Skip resuming queue (just do the visuals)
*/
const retryRequests = function (skipResumeQueue) {
clearInterval(currentInterval);
toggleThrobber(true);
if (!skipResumeQueue) {
requestQueue.resumeQueue();
}
};
/**
* Increments retry interval
*/
const incrementRetryInterval = function () {
intervalIndex += 1;
if (intervalIndex >= retryIntervals.length) {
intervalIndex = retryIntervals.length - 1;
}
};
/**
* Starts counting down to retrying queued requests.
*
* @param forceDelayedShow
*/
const startCountDown = function (forceDelayedShow) {
// Already showing, wait for retry
if (isShowing) {
return;
}
toggleThrobber(false);
if (!isShowing) {
if (forceDelayedShow) {
// Must force delayed show since dialog may be hiding, and confirmation dialog does not
// support this.
setTimeout(function () {
offlineDialog.show(0);
}, 100);
} else {
offlineDialog.show(0);
}
}
isShowing = true;
startTime = new Date().getTime();
incrementRetryInterval();
clearInterval(currentInterval);
currentInterval = setInterval(updateCountDown, 100);
};
/**
* Updates the count down timer. Retries requests when time expires.
*/
const updateCountDown = function () {
const time = new Date().getTime();
const timeElapsed = Math.floor((time - startTime) / 1000);
const timeLeft = retryIntervals[intervalIndex] - timeElapsed;
countDownNum.textContent = timeLeft.toString();
// Retry interval reached, retry requests
if (timeLeft <= 0) {
retryRequests();
}
};
/**
* Add request to offline request queue. Only supports posts for now.
*
* @param {string} url The request url
* @param {Object} data The request data
*/
this.add = function (url, data) {
requestQueue.add(url, data);
};
};
return offlineRequestQueue;
})(H5P.RequestQueue, H5P.ConfirmationDialog);