shaka-player
Version:
DASH/EME video player library
316 lines (278 loc) • 8.59 kB
JavaScript
/*! @license
* Shaka Player
* Copyright 2016 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
goog.provide('shaka.util.Platform');
goog.require('shaka.util.Timer');
/**
* A wrapper for platform-specific functions.
*
* @final
*/
shaka.util.Platform = class {
/**
* Check if the current platform supports media source. We assume that if
* the current platform supports media source, then we can use media source
* as per its design.
*
* @return {boolean}
*/
static supportsMediaSource() {
// Browsers that lack a media source implementation will have no reference
// to |window.MediaSource|. Platforms that we see having problematic media
// source implementations will have this reference removed via a polyfill.
if (!window.MediaSource) {
return false;
}
// Some very old MediaSource implementations didn't have isTypeSupported.
if (!MediaSource.isTypeSupported) {
return false;
}
return true;
}
/**
* Returns true if the media type is supported natively by the platform.
*
* @param {string} mimeType
* @return {boolean}
*/
static supportsMediaType(mimeType) {
const video = shaka.util.Platform.anyMediaElement();
return video.canPlayType(mimeType) != '';
}
/**
* Check if the current platform is MS Edge.
*
* @return {boolean}
*/
static isEdge() {
// Legacy Edge contains "Edge/version".
// Chromium-based Edge contains "Edg/version" (no "e").
if (navigator.userAgent.match(/Edge?\//)) {
return true;
}
return false;
}
/**
* Check if the current platform is Legacy Edge.
*
* @return {boolean}
*/
static isLegacyEdge() {
// Legacy Edge contains "Edge/version".
// Chromium-based Edge contains "Edg/version" (no "e").
if (navigator.userAgent.match(/Edge\//)) {
return true;
}
return false;
}
/**
* Check if the current platform is MS IE.
*
* @return {boolean}
*/
static isIE() {
return shaka.util.Platform.userAgentContains_('Trident/');
}
/**
* Check if the current platform is an Xbox One.
*
* @return {boolean}
*/
static isXboxOne() {
return shaka.util.Platform.userAgentContains_('Xbox One');
}
/**
* Check if the current platform is a Tizen TV.
*
* @return {boolean}
*/
static isTizen() {
return shaka.util.Platform.userAgentContains_('Tizen');
}
/**
* Check if the current platform is a Tizen 4 TV.
*
* @return {boolean}
*/
static isTizen4() {
return shaka.util.Platform.userAgentContains_('Tizen 4');
}
/**
* Check if the current platform is a Tizen 3 TV.
*
* @return {boolean}
*/
static isTizen3() {
return shaka.util.Platform.userAgentContains_('Tizen 3');
}
/**
* Check if the current platform is a Tizen 2 TV.
*
* @return {boolean}
*/
static isTizen2() {
return shaka.util.Platform.userAgentContains_('Tizen 2');
}
/**
* Check if the current platform is a WebOS.
*
* @return {boolean}
*/
static isWebOS() {
return shaka.util.Platform.userAgentContains_('Web0S');
}
/**
* Check if the current platform is a Google Chromecast.
*
* @return {boolean}
*/
static isChromecast() {
return shaka.util.Platform.userAgentContains_('CrKey');
}
/**
* Check if the current platform is Google Chrome.
*
* @return {boolean}
*/
static isChrome() {
// The Edge user agent will also contain the "Chrome" keyword, so we need
// to make sure this is not Edge.
return shaka.util.Platform.userAgentContains_('Chrome') &&
!shaka.util.Platform.isEdge();
}
/**
* Check if the current platform is from Apple.
*
* Returns true on all iOS browsers and on desktop Safari.
*
* Returns false for non-Safari browsers on macOS, which are independent of
* Apple.
*
* @return {boolean}
*/
static isApple() {
return !!navigator.vendor && navigator.vendor.includes('Apple')
&& !shaka.util.Platform.isTizen();
}
/**
* Returns a major version number for Safari, or Safari-based iOS browsers.
*
* For example:
* - Safari 13.0.4 on macOS returns 13.
* - Safari on iOS 13.3.1 returns 13.
* - Chrome on iOS 13.3.1 returns 13 (since this is based on Safari/WebKit).
* - Chrome on macOS returns null (since this is independent of Apple).
*
* Returns null on Firefox on iOS, where this version information is not
* available.
*
* @return {?number} A major version number or null if not iOS.
*/
static safariVersion() {
// All iOS browsers and desktop Safari will return true for isApple().
if (!shaka.util.Platform.isApple()) {
return null;
}
// This works for iOS Safari and desktop Safari, which contain something
// like "Version/13.0" indicating the major Safari or iOS version.
let match = navigator.userAgent.match(/Version\/(\d+)/);
if (match) {
return parseInt(match[1], /* base= */ 10);
}
// This works for all other browsers on iOS, which contain something like
// "OS 13_3" indicating the major & minor iOS version.
match = navigator.userAgent.match(/OS (\d+)(?:_\d+)?/);
if (match) {
return parseInt(match[1], /* base= */ 10);
}
return null;
}
/**
* Guesses if the platform is a mobile one (iOS or Android).
*
* @return {boolean}
*/
static isMobile() {
if (/(?:iPhone|iPad|iPod|Android)/.test(navigator.userAgent)) {
// This is Android, iOS, or iPad < 13.
return true;
}
// Starting with iOS 13 on iPad, the user agent string no longer has the
// word "iPad" in it. It looks very similar to desktop Safari. This seems
// to be intentional on Apple's part.
// See: https://forums.developer.apple.com/thread/119186
//
// So if it's an Apple device with multi-touch support, assume it's a mobile
// device. If some future iOS version starts masking their user agent on
// both iPhone & iPad, this clause should still work. If a future
// multi-touch desktop Mac is released, this will need some adjustment.
//
// As of January 2020, this is mainly used to adjust the default UI config
// for mobile devices, so it's low risk if something changes to break this
// detection.
return shaka.util.Platform.isApple() && navigator.maxTouchPoints > 1;
}
/**
* Check if the user agent contains a key. This is the best way we know of
* right now to detect platforms. If there is a better way, please send a
* PR.
*
* @param {string} key
* @return {boolean}
* @private
*/
static userAgentContains_(key) {
const userAgent = navigator.userAgent || '';
return userAgent.includes(key);
}
/**
* For canPlayType queries, we just need any instance.
*
* First, use a cached element from a previous query.
* Second, search the page for one.
* Third, create a temporary one.
*
* Cached elements expire in one second so that they can be GC'd or removed.
*
* @return {!HTMLMediaElement}
*/
static anyMediaElement() {
const Platform = shaka.util.Platform;
if (Platform.cachedMediaElement_) {
return Platform.cachedMediaElement_;
}
if (!Platform.cacheExpirationTimer_) {
Platform.cacheExpirationTimer_ = new shaka.util.Timer(() => {
Platform.cachedMediaElement_ = null;
});
}
Platform.cachedMediaElement_ = /** @type {HTMLMediaElement} */(
document.getElementsByTagName('video')[0] ||
document.getElementsByTagName('audio')[0]);
if (!Platform.cachedMediaElement_) {
Platform.cachedMediaElement_ = /** @type {!HTMLMediaElement} */(
document.createElement('video'));
}
Platform.cacheExpirationTimer_.tickAfter(/* seconds= */ 1);
return Platform.cachedMediaElement_;
}
/**
* Returns true if the platform requires encryption information in all init
* segments. For such platforms, MediaSourceEngine will attempt to work
* around a lack of such info by inserting fake encryption information into
* initialization segments.
*
* @return {boolean}
* @see https://github.com/google/shaka-player/issues/2759
*/
static requiresEncryptionInfoInAllInitSegments() {
const Platform = shaka.util.Platform;
return Platform.isTizen() || Platform.isXboxOne();
}
};
/** @private {shaka.util.Timer} */
shaka.util.Platform.cacheExpirationTimer_ = null;
/** @private {HTMLMediaElement} */
shaka.util.Platform.cachedMediaElement_ = null;