I am trying to add a Google+ button to all my domains but when the button is clicked, I get an error back from google (Red exclamation mark in warning triangle)
I have tried a number of things and have worked out the following.
Google+ will try to access my site when the button is clicked to verify the site. My site fails at this point.
The reason for this is that we have multiple domains and a cross-site session script in place that requires us to forward a user to our sessions server on their first visit to a new domain, then forward the user back to the domain they were trying to access.
To forward the user I am using the PHP function header(“Location: ” . SESSION_SERVER);
When Google gets the header asking for the redirect it fails and therefore makes my site unable to be +1’d.
The stuff I know about the Google+ verification bot is that it doesn’t have cookies enabled and that it uses a standard google chrome user agent (correct me if I’m wrong on this one)
I think the solution is to be able to detect the google+ bot and not redirect it or have a way of redirecting it without it interfering with the site passing the bot’s verification process.
(Oh, and the site I am testing on is http://www.taxicode.com)
We solved this problem a while ago now so I thought it would be appropriate to post the solution.
We discovered the Google+ bot set the server property HTTP_X_GOOG_SOURCE. That allowed us to detect it and stop the redirection.
In PHP:
if (isset($_SERVER[‘HTTP_X_GOOG_SOURCE’])) {
}