On the 1st February this year, JanRain decided to shut down the myOpenID service which I'd been using up until recently for logging into OpenID-enabled sites such as Stack Overflow and others using my own domain. Because of this, I've now switched to using my Google apps account to replace myOpenID.

It was surprisingly difficult to find out how to do this, but I found a post by Danny Tuppeny which gave me almost exactly what I needed. However, his example is back from before the days of custom Google+ URLs, which do change things: I found that the openid2.local_id value needed to be tweaked as below to ensure the relying party (in this case, Stack Overflow) received my URL rather than a Google one.

<link rel="openid2.provider" href="https://www.google.com/accounts/o8/ud?source=profiles">
<link rel="openid2.local_id" href="http://profiles.google.com/114245777374210891319">

If you're wondering how to find your big long number, there are two approaches:

1. Log into Google+ and copy the URL for the "profile" menu option. This will have a URL which looks like https://plus.google.com/u/0/114245777374210891319. Just take the final segment and add it to http://profiles.google.com/.
2. Use only the openid2.provider tag on your site and try logging into Stack Overflow. You'll get asked if you want to create a new account using the given URL, which will be displayed. Of course, you'll want to hit the cancel option, but you'll now have seen what you're being identified as. This is what you'll need for your openid2.local_id value.

This resulted in everything working exactly as before (I still use my own URL to log into Stack Overflow and so on) and the only difference is that it's Google now verifying my identity. Perfect.