Humanize filesize

angular-filesize.js

app.filter('bytes', function() {
	return function(bytes, precision) {
		if (isNaN(parseFloat(bytes)) || !isFinite(bytes)) return '-';
		if (typeof precision === 'undefined') precision = 1;
		var units = ['bytes', 'kB', 'MB', 'GB', 'TB', 'PB'];
		var number = Math.floor(Math.log(bytes) / Math.log(1024));
		return (bytes / Math.pow(1024, Math.floor(number))).toFixed(precision) +  ' ' + units[number];
	};
});

filesize.cljs

(ns ...
  (:require [goog.string :as gs])

(def ^:private units ["bytes" "kB" "MB" "GB" "TB" "PB"])
(def ^:private largest-unit (dec (count units)))
(def ^:private system 1000) ; or 1024 for binary sizes

(defn humanize-filesize
  [bytes & [fmt]]
  (let [unit (min largest-unit (js/Math.floor (/ (js/Math.log bytes) (js/Math.log system))))
        size (/ bytes (js/Math.pow system unit))]
    (gs/format (or fmt "%0.1f %s") size (get units unit))))