How do skype extensions for browsers actually work?

Question

We have plans of developing a web application that will have to communicate with our locally running application. One of the possible options is using browser extensions. I was looking into how Skype add-ons to browsers communicate with Skype client. In Firefox, Skype add-on inserts a piece of HTML when it encounters a phone number. Is this

<span skypeaction="...">

processed by a Skype extension which makes a call using Skype API? Do extensions for other browsers use Skype API or other communications mechanism?

Answer 1

The Skype extension would use regular expressions to search for valid and visible phone numbers displayed on a webpage, and as you say it would wrap a span class around it.

The span class would be defined within the extension code, and would insert the skype icon along with a clickable link that launches the skype application.

You also see similar functionality from iTunes and IRC, they have links in the irc://... format.

Answer 2

I did a bit of research and here's what I found. When the user clicks on the Skype link injected by the extension, the extension creates a new Skype process and passes it the parameters specifying the action and the number. Custom protocol handler is not used.