Awasu passes a string to plugins via the AppPluginServerUrl parameter in the INI file that might look like this:
[System] AppPluginServerUrl = http://127.0.0.1:12345
Plugins can then use this value to generate and insert URL's into a page that would then look like this:
Awasu will be listening on the appropriate port and receives the HTTP request when the user clicks on the link. It figures out which plugin to send the request to (using the plugin ID embedded in the URL) and inserts the request name and parameters into the plugin's INI file, like this:
[System] Command = ProcessRequest PluginRequest = foo/bar ParamString = p1=Hello&p2=World
The plugin can then use this information to process the request appropriately.