Google Reader Subscribers Count mod

grsc.user.js

// ==UserScript==
// @name           Google Reader Subscribers Count mod
// @description    Show how many subscribers to the feed with google reader.
// @include        http:*
// @exclude        http://www.google.tld/reader/view/*
// @charset        utf-8
// @compatibility  Firefox
// @namespace      http://twitter.com/xulapp
// @author         xulapp
// @license        MIT License
// @version        2010/12/25 13:00 +09:00
// ==/UserScript==
// @version        2009/11/22 07:26 +09:00


setTimeout(function() {
	const READER_BASE_URI = 'https://www.google.com/reader/view/feed/';
	const CACHE_EXPIRES = 24 * 60 * 60 * 1000;

	var feeds = document.evaluate('descendant::link[@rel="alternate" and (@type="application/rss+xml" or @type="application/atom+xml")]', document, null, 7, null);
	var len = feeds.snapshotLength;
	if (!len) return;

	var cache = JSON.parse(GM_getValue('cache', '{}'));
	var limit = Date.now() - CACHE_EXPIRES;
	for (let [url, [time]] in Iterator(cache)) {
		if (time < limit)
			delete cache[url];
	}
	GM_setValue('cache', JSON.stringify(cache));

	GM_addStyle('' + <><![CDATA[
		#grsc-container {
			position: fixed !important;
			right: 4px !important;
			bottom: 0 !important;
			padding: 0 4px !important;
			border-radius: 4px 4px 0 0 !important;
			-moz-border-radius: 4px 4px 0 0 !important;
			background: #99ccff !important;
			color: #666666 !important;
			font: 8pt normal !important;
			z-index: 2147483647 !important;
		}
		#grsc-container > a {
			color: #0000ff !important;
			font-weight: bold !important;
		}
		#grsc-container > a.failed {
			color: #ff0000 !important;
		}
	]]></>);

	var container = document.createElement('div');
	container.id = 'grsc-container';
	for (let i = 0; i < len; i++) {
		if (i)
			container.appendChild(document.createTextNode(' + '));
		let feed = feeds.snapshotItem(i);
		let anchor = document.createElement('a');
		anchor.href = READER_BASE_URI + encodeURIComponent(feed.href);
		anchor.title = feed.title;
		anchor.textContent = '-'
		container.appendChild(anchor);
		loadDetails(feed.href, function(data) {
			if (data) {
				var {subscribers, velocity} = data;
				anchor.textContent = subscribers < 0 ? 0 : subscribers;
				anchor.title += ' (vel: ' + velocity + ')';
			} else {
				anchor.classList.add('failed');
			}
		});
	}
	container.appendChild(document.createTextNode(' subscriber'));
	document.body.appendChild(container);

	function loadDetails(url, callback) {
		if (url in cache) {
			setTimeout(function() callback(cache[url][1]), 0);
			return;
		}
		GM_xmlhttpRequest({
			method: 'GET',
			url: 'https://www.google.com/reader/api/0/stream/details?fetchTrends=false&output=json&s=' + encodeURIComponent('feed/' + url),
			onload: function onLoad(response) {
				if (response.status !== 200) {
					callback();
					return;
				}
				var details = JSON.parse(response.responseText);
				var data = {
					subscribers: +details.subscribers.replace(/,/g, ''),
					velocity: +details.velocity,
				};
				cache[url] = [Date.now(), data];
				GM_setValue('cache', JSON.stringify(cache));
				callback(data);
			},
		});
		
	}
}, 0);

Useful, do you know what the velocity parameter stands for?

Maybe it means "Posts per week".

Could be, 10x for the clarification. But still... in my case it should be 0,something, while it is 2.1 Interestingly there is not much information about it online.