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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 | 20x 20x 20x 32x 32x 9x 9x 32x 10x 10x 10x 1x 9x 9x 25x 25x 3x 1x 1x 2x 11x 11x 1x 1x 19x 19x 19x 19x 19x 20x 20x 20x 20x 20x 19x 19x 18x 4x 4x 20x 20x 20x 20x 4x 4x 59x 35x 9x 9x 9x 9x 9x 9x 5x 36x 36x | import $ from 'jquery'; /** * Instances of SmartInterval extend the functionality of `setInterval`, make it configurable * and controllable by a public API. * * This component has two intervals: * * - current interval - when the page is visible - defined by `startingInterval`, `maxInterval`, and `incrementByFactorOf` * - Example: * - `startingInterval: 10000`, `maxInterval: 240000`, `incrementByFactorOf: 2` * - results in `10s, 20s, 40s, 80s, ..., 240s`, it stops increasing at `240s` and keeps this interval indefinitely. * - hidden interval - when the page is not visible * * Visibility transitions: * * - `visible -> not visible` * - `document.addEventListener('visibilitychange', () => ...)` * * > This event fires with a visibilityState of hidden when a user navigates to a new page, switches tabs, closes the tab, minimizes or closes the browser, or, on mobile, switches from the browser to a different app. * * Source [Document: visibilitychange event - Web APIs | MDN](https://developer.mozilla.org/en-US/docs/Web/API/Document/visibilitychange_event) * * - `window.addEventListener('blur', () => ...)` - every time user clicks somewhere else then in the browser page * - `not visible -> visible` * - `document.addEventListener('visibilitychange', () => ...)` same as the transition `visible -> not visible` * - `window.addEventListener('focus', () => ...)` * * The combination of these two listeners can result in an unexpected resumption of polling: * * - switch to a different window (causes `blur`) * - switch to a different desktop (causes `visibilitychange` (not visible)) * - switch back to the original desktop (causes `visibilitychange` (visible)) * - *now the polling happens even in window that user doesn't work in* */ export default class SmartInterval { /** * @param { function } opts.callback Function that returns a promise, called on each iteration * unless still in progress (required) * @param { milliseconds } opts.startingInterval `currentInterval` is set to this initially * @param { milliseconds } opts.maxInterval `currentInterval` will be incremented to this * @param { milliseconds } opts.hiddenInterval `currentInterval` is set to this * when the page is hidden * @param { integer } opts.incrementByFactorOf `currentInterval` is incremented by this factor * @param { boolean } opts.lazyStart Configure if timer is initialized on * instantiation or lazily * @param { boolean } opts.immediateExecution Configure if callback should * be executed before the first interval. */ constructor(opts = {}) { this.cfg = { callback: opts.callback, startingInterval: opts.startingInterval, maxInterval: opts.maxInterval, hiddenInterval: opts.hiddenInterval, incrementByFactorOf: opts.incrementByFactorOf, lazyStart: opts.lazyStart, immediateExecution: opts.immediateExecution, }; this.state = { intervalId: null, currentInterval: this.cfg.startingInterval, pagevisibile: true, }; this.initInterval(); } /* public */ start() { const { cfg, state } = this; if (cfg.immediateExecution && !this.isLoading) { cfg.immediateExecution = false; this.triggerCallback(); } state.intervalId = window.setInterval(() => { Iif (this.isLoading) { return; } this.triggerCallback(); if (this.getCurrentInterval() === cfg.maxInterval) { return; } this.incrementInterval(); this.resume(); }, this.getCurrentInterval()); } // cancel the existing timer, setting the currentInterval back to startingInterval cancel() { this.setCurrentInterval(this.cfg.startingInterval); this.stopTimer(); } onVisibilityHidden() { if (this.cfg.hiddenInterval) { this.setCurrentInterval(this.cfg.hiddenInterval); this.resume(); } else { this.cancel(); } } // start a timer, using the existing interval resume() { this.stopTimer(); // stop existing timer, in case timer was not previously stopped this.start(); } onVisibilityVisible() { this.cancel(); this.start(); } destroy() { document.removeEventListener('visibilitychange', this.onVisibilityChange); window.removeEventListener('blur', this.onWindowVisibilityChange); window.removeEventListener('focus', this.onWindowVisibilityChange); this.cancel(); // eslint-disable-next-line @gitlab/no-global-event-off $(document).off('visibilitychange').off('beforeunload'); } /* private */ initInterval() { const { cfg } = this; Eif (!cfg.lazyStart) { this.start(); } this.initVisibilityChangeHandling(); this.initPageUnloadHandling(); } triggerCallback() { this.isLoading = true; this.cfg .callback() .then(() => { this.isLoading = false; }) .catch((err) => { this.isLoading = false; throw err; }); } onWindowVisibilityChange(e) { this.state.pagevisibile = e.type === 'focus'; this.handleVisibilityChange(); } onVisibilityChange(e) { this.state.pagevisibile = e.target.visibilityState === 'visible'; this.handleVisibilityChange(); } initVisibilityChangeHandling() { // cancel interval when tab or window is no longer shown (prevents cached pages from polling) document.addEventListener('visibilitychange', this.onVisibilityChange.bind(this)); window.addEventListener('blur', this.onWindowVisibilityChange.bind(this)); window.addEventListener('focus', this.onWindowVisibilityChange.bind(this)); } initPageUnloadHandling() { // TODO: Consider refactoring in light of turbolinks removal. // prevent interval continuing after page change, when kept in cache by Turbolinks $(document).on('beforeunload', () => this.cancel()); } handleVisibilityChange() { const intervalAction = this.isPageVisible() ? this.onVisibilityVisible : this.onVisibilityHidden; intervalAction.apply(this); } getCurrentInterval() { return this.state.currentInterval; } setCurrentInterval(newInterval) { this.state.currentInterval = newInterval; } incrementInterval() { const { cfg } = this; const currentInterval = this.getCurrentInterval(); Iif (cfg.hiddenInterval && !this.isPageVisible()) return; let nextInterval = currentInterval * cfg.incrementByFactorOf; Iif (nextInterval > cfg.maxInterval) { nextInterval = cfg.maxInterval; } this.setCurrentInterval(nextInterval); } isPageVisible() { return this.state.pagevisibile; } stopTimer() { const { state } = this; state.intervalId = window.clearInterval(state.intervalId); } } |