FBGroupInvitations.js

function GroupInvitations() {
  this.event_id = 517949684905901;
	this.member_ids = [];
	this.semaphore = 0;
}

GroupInvitations.prototype = {
	unlock: function() {
		if (++(this.semaphore) === 3) {
			resultStr = this.member_ids.join(',');
			invitationURL = '/' + this.event_id + '/invited?users=' + resultStr; 
			console.log(this.member_ids.length);
			console.log(invitationURL);
			FB.api(invitationURL, 'post', function(response) {
				console.log(response);
			});
		}
		return this.semaphore;
	}
};

FB.getLoginStatus(function(response) {
	gi = new GroupInvitations();

	if (response.status != 'connected')
		return;
	
	// DATspace
	FB.api('/141673622569388/members', function(result) {
		for (var i = 0; i < result.data.length; i++)
			gi.member_ids.push(result.data[i].id);
		gi.unlock();
	});

	// WICS
	FB.api('/2200392077/members', function(result) {
		for (var i = 0; i < result.data.length; i++)
			gi.member_ids.push(result.data[i].id);
		gi.unlock();
	});

	// ACM
	FB.api('/228954137162541/members', function(result) {
		for (var i = 0; i < result.data.length; i++)
			gi.member_ids.push(result.data[i].id);
		gi.unlock();
	});
});