1. Run Rapise Npm Console and run:

npm install deasync

2. Wrap you call in a function like that (it calls AsyncLibraryCall and returns the result):

function DoSomethingSync()
{
	var deasync = require("deasync");
	var result = undefined;
    var completed = false;
	
	async function asyncOperation()
	{
		result = await AsyncLibraryCall();
		completed = true;
	}
	
	asyncOperation();

	while(!completed)
	{
		deasync.runLoopOnce();
	}

	return result;
}

3. Note: You must use NPM console from Rapise, because Rapise has own runtime.