43 lines
1.1 KiB
JavaScript
43 lines
1.1 KiB
JavaScript
/* global window */
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// eslint-disable-next-line func-names
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(function() {
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window.libloki = window.libloki || {};
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function consolidateLists(lists, threshold, selector = x => x) {
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if (typeof threshold !== 'number') {
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throw Error('Provided threshold is not a number');
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}
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if (typeof selector !== 'function') {
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throw Error('Provided selector is not a function');
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}
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// calculate list size manually since `Set`
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// does not have a `length` attribute
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let numLists = 0;
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const occurences = {};
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const values = {};
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lists.forEach(list => {
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numLists += 1;
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list.forEach(item => {
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const key = selector(item);
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if (!(key in occurences)) {
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occurences[key] = 1;
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values[key] = item;
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} else {
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occurences[key] += 1;
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}
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});
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});
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const scaledThreshold = numLists * threshold;
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return Object.keys(occurences)
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.filter(key => occurences[key] >= scaledThreshold)
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.map(key => values[key]);
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}
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window.libloki.serviceNodes = {
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consolidateLists,
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};
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})();
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