session-desktop/js/expiring_messages.js
lilia 25ee61d3cb Fix timers after suspend/resume/pause
We use timers to decide when to query and delete expired messages or
when to perform signed key rotations.

Internally, timers are counters that get updated when the CPU ticks, so
if the CPU sleeps, the timer will stop counting, and start again after
it wakes up, ignoring the intervening passage of wall clock time.

To fix this, without having to query the database or other potentially
high overhead operations too often, use an interval to frequently check
the wall clock time. If time jumps forward, trigger a global event so
other listeners can update their possibly-inaccurate timers.

https://stackoverflow.com/questions/6346849/what-happens-to-settimeout-when-the-computer-goes-to-sleep
https://stackoverflow.com/questions/4079115/can-any-desktop-browsers-detect-when-the-computer-resumes-from-sleep

// FREEBIE
2017-03-01 14:36:40 -08:00

103 lines
3 KiB
JavaScript

/*
* vim: ts=4:sw=4:expandtab
*/
;(function() {
'use strict';
window.Whisper = window.Whisper || {};
function destroyExpiredMessages() {
// Load messages that have expired and destroy them
var expired = new Whisper.MessageCollection();
expired.on('add', function(message) {
console.log('message', message.get('sent_at'), 'expired');
message.destroy();
message.getConversation().trigger('expired', message);
});
expired.on('reset', checkExpiringMessages);
expired.fetchExpired();
}
var timeout;
function checkExpiringMessages() {
// Look up the next expiring message and set a timer to destroy it
var expiring = new Whisper.MessageCollection();
expiring.once('add', function(next) {
var expires_at = next.get('expires_at');
console.log('next message expires', new Date(expires_at));
var wait = expires_at - Date.now();
if (wait < 0) { wait = 0; }
clearTimeout(timeout);
timeout = setTimeout(destroyExpiredMessages, wait);
});
expiring.fetchNextExpiring();
}
window.ExpiringMessagesListener = {
init: function() {
checkExpiringMessages();
window.events.on('timetravel', checkExpiringMessages);
},
update: checkExpiringMessages
};
var TimerOption = Backbone.Model.extend({
getName: function() {
return i18n([
'timerOption', this.get('time'), this.get('unit'),
].join('_')) || moment.duration(this.get('time'), this.get('unit')).humanize();
},
getAbbreviated: function() {
return i18n([
'timerOption', this.get('time'), this.get('unit'), 'abbreviated'
].join('_'));
}
});
Whisper.ExpirationTimerOptions = new (Backbone.Collection.extend({
model: TimerOption,
getName: function(seconds) {
if (!seconds) {
seconds = 0;
}
var o = this.findWhere({seconds: seconds});
if (o) { return o.getName(); }
else {
return [seconds, 'seconds'].join(' ');
}
},
getAbbreviated: function(seconds) {
if (!seconds) {
seconds = 0;
}
var o = this.findWhere({seconds: seconds});
if (o) { return o.getAbbreviated(); }
else {
return [seconds, 's'].join('');
}
}
}))([
[ 0, 'seconds' ],
[ 5, 'seconds' ],
[ 10, 'seconds' ],
[ 30, 'seconds' ],
[ 1, 'minute' ],
[ 5, 'minutes' ],
[ 30, 'minutes' ],
[ 1, 'hour' ],
[ 6, 'hours' ],
[ 12, 'hours' ],
[ 1, 'day' ],
[ 1, 'week' ],
].map(function(o) {
var duration = moment.duration(o[0], o[1]); // 5, 'seconds'
return {
time: o[0],
unit: o[1],
seconds: duration.asSeconds()
};
}));
})();