coach-core
Version:
Core package for the Coach.
230 lines (211 loc) • 6.87 kB
JavaScript
;
const util = {
/**
* Make your URL absolute.
* @memberof util
* @param {String} url The URL to convert to absolute.
* @returns {String} the absolute URL including host/protocol.
*/
getAbsoluteURL: function (url) {
const a = window.document.createElement('a');
a.href = url;
return a.href;
},
/**
* Get the hostname from a URL
* @memberof util
* @param {String} url The URL.
* @returns {String} the hostname from the URL.
*/
getHostname: function (url) {
const a = window.document.createElement('a');
a.href = url;
return a.hostname;
},
/**
* Checks if an element exist in an array.
*
* @memberof util
* @param {String} element the element.
* @param {Array} array the array.
* @returns {Boolean} true if the element exist.
*/
exists: function (element, array) {
return array.some(function (e) {
return e === element;
});
},
/**
* Returns an array filter function for finding tags with an attribute specified value, matching case insensitive.
* @param attributeName the name of the attribute to look for (html attribute values are always case insensitive).
* @param attributeValue the value to match against, ignoring case.
* @returns {Function} function that can be passed to Array#filter
*/
caseInsensitiveAttributeValueFilter: function (
attributeName,
attributeValue
) {
return function (item) {
const attribute = item.getAttribute(attributeName) || '';
if (attribute.toLowerCase() === attributeValue.toLowerCase()) {
return item;
}
return undefined;
};
},
/**
* Is the connection used for the main document using HTTP/2?
* Works in Chrome, Firefox, Edge and other browsers that supports Resource Timing
* API v2 (not Safari yet).
* @memberof util
* @returns {Boolean} true if the connection is HTTP/2
*/
isHTTP2: function () {
const type = util.getConnectionType().toLowerCase();
return type === 'h2' || type.startsWith('spdy');
},
/**
* Is the connection used for the main document using HTTP/3?
* @memberof util
* @returns {Boolean} true if the connection is HTTP/3
*/
isHTTP3: function () {
const type = util.getConnectionType().toLowerCase();
return type.startsWith('h3');
},
/**
* Get the connection type used for the main document. Works in Chrome, Firefox,
* Edge and + browsers that support Resource Timing
* API v2.
* @memberof util
* @returns {String} http/1 or h2 for http 1 and 2 respectively. 'unknown' if browser lacks api to determine it.
*/
getConnectionType: function () {
// it's easy in Chrome
if (
window.performance.getEntriesByType('navigation') &&
window.performance.getEntriesByType('navigation')[0] &&
window.performance.getEntriesByType('navigation')[0].nextHopProtocol
) {
return window.performance.getEntriesByType('navigation')[0]
.nextHopProtocol;
} else if (
window.performance &&
window.performance.getEntriesByType &&
window.performance.getEntriesByType('resource')
) {
// if you support resource timing v2
// it's kind of easy too
const resources = window.performance.getEntriesByType('resource');
// now we "only" need to know if it is v2
if (resources.length > 1 && resources[0].nextHopProtocol) {
// if it's the same domain, say it's OK
const host = document.domain;
for (let i = 0, len = resources.length; i < len; i++) {
if (host === util.getHostname(resources[i].name)) {
return resources[i].nextHopProtocol;
}
}
}
}
return 'unknown';
},
/**
* Get JavaScript requests that are loaded synchronously. All URLs are absolute.
* @memberof util
* @param {Object} parentElement the parent element that has all the scripts.
* @returns {Array} an array with the URL to each JavaScript file that is loaded synchronously.
*/
getSynchJSFiles: function (parentElement) {
const scripts = Array.prototype.slice.call(
parentElement.getElementsByTagName('script')
);
return scripts
.filter(function (s) {
return !s.async && s.src && !s.defer;
})
.map(function (s) {
return util.getAbsoluteURL(s.src);
});
},
/**
* Get JavaScript requests that are loaded asynchronously. All URLs are absolute.
* @memberof util
* @param {Object} parentElement the parent element that has all the scripts.
* @returns {Array} an array with the URL to each JavaScript file that are loaded asynchronously.
*/
getAsynchJSFiles: function (parentElement) {
const scripts = Array.prototype.slice.call(
parentElement.getElementsByTagName('script')
);
return scripts
.filter(function (s) {
return s.async && s.src;
})
.map(function (s) {
return util.getAbsoluteURL(s.src);
});
},
/**
* Get Resource Hints hrefs by type
* @memberof util
* @param {String} type the name of the Resources hint: dns-prefetch, preconnect, prefetch, prerender
* @returns {Array} an array of matching hrefs
*/
getResourceHintsHrefs: function (type) {
const links = Array.prototype.slice.call(
window.document.head.getElementsByTagName('link')
);
return links
.filter(function (link) {
return link.rel === type;
})
.map(function (link) {
return link.href;
});
},
/**
* Get CSS requests. All URLs are absolute.
* @memberof util
* @param {Object} parentElement the parent element that has all the scripts.
* @returns {Array} an array with the URL to each CSS file that is loaded synchronously.
*/
getCSSFiles: function (parentElement) {
const links = Array.prototype.slice.call(
parentElement.getElementsByTagName('link')
);
return links
.filter(function (link) {
// make sure we skip data:
return link.rel === 'stylesheet' && !link.href.startsWith('data:');
})
.map(function (link) {
return util.getAbsoluteURL(link.href);
});
},
plural: function (number, text) {
if (number > 1) {
text += 's';
}
return `${number} ${text}`;
},
/**
* Get the size of an asset. Will try to use the Resource Timing V2. If that's
* not available or the asset size is unknown we report 0.
**/
getTransferSize: function (url) {
const entries = window.performance.getEntriesByName(url, 'resource');
if (entries.length === 1 && typeof entries[0].transferSize === 'number') {
return entries[0].transferSize;
} else {
return 0;
}
},
ms(ms) {
if (ms < 1000) {
return ms + ' ms';
} else {
return Number(ms / 1000).toFixed(3) + ' s';
}
}
};