The hot shoe has developed over time and is different from brand to brand, but fundamentally it is still the same. The main important parts are the big center connector and the chassis of the camera. I think from memory the center connector and chassis are a contacts normally closed switch, when the shutter is opened the contacts open (I am not 100% certain I have this the right way round) but it would be best to check this yourself with a multimeter.
The other smaller contacts on the hotshoe are specific from brand to brand for communication between the camera and the flash for exposure control.