I often attend open source activities offline, but remembering the date and location of those activities is not easy. In China, I just collect those information from mailing list, WeChat or Telegram, then add them to Calendar.app on my iPhone manually.

There is a method to publish your activities on Internet, and it is called iCalendar, which is defined by RFC 2445. I can easily publish a public calendar using my iPhone via iCloud or via Google Calendar. Though it is not very GNU, but so far so good, at least it works.

Then I want to display it on my blog or website.

After a few google clicks, I found out that there is already an ugly service called 'zetabee'.

You simply add a few lines of javascript, then you can render a public iCalendar subscription in your web page:

<link rel="stylesheet" type="text/css" href="https://zetabee.com/icaljs/res/embed.css" />
<div id="icjs"></div>
<script>(function() {
 // Customize these as you wish
 var pastdays   = 0;       // # of past days to show (0 to 30)
 var futuredays = 60;      // # of future days to show (0 to 365)
 var cachemins  = 10;      // # of minutes to wait before refreshing calendar data (2 to 1440)
 var container  = "icjs";  // ID of div to embed calendar into
 // Do not change anything below this
 var s = document.createElement("script"); s.type = "text/javascript"; s.async = true; s.src = "https://zetabee.com/icaljs/embed?calid=RDU1a2ZIWlVyY0xzRDh0dHdWR1oxQT09&offset=-8&cachemins=" + cachemins + "&futuredays=" + futuredays + "&pastdays=" + pastdays + "&container=" + container;
 (document.getElementsByTagName("head")[0] || document.getElementsByTagName("body")[0]).appendChild(s);
})();</script>

But still you have to rely on the service provided by zetabee, and it is far from simple and beautiful.

What I propose is that we create a standalone javascript iCalendar render library to display published iCalendar links.