Facebook® Application Development For Dummies®

Chapter 8

Knowing What Information You Have Access To

In This Chapter

• Acquiring publicly accessible information
• Prompting users for permissions
• Determining the users who are visiting your Web site
• Accessing offline data with scripts

With an accessible API and such a broad set of information you can get about each user, it's good to know exactly what information that you, as a developer, have access to. This is a source of frustration for many; notice that many of the calls to Graph API that you make in Chapter 7 give some sort of message about an “access token.” Although Facebook makes this information available to developers, ultimately users decide what elements of information they allow developers access to. Facebook is strict on ensuring its users' privacy, and this bleeds from every piece of the UI on Facebook.com all the way into the applications and Web sites to which users access and provide information through Facebook.

In this chapter, I show you how to prompt the user to get the information you need as a developer. I discuss what you have access to without any permissions (other than an authenticated user), and how to get access to more detailed information when the user gives you the permission you need. In addition, I show you a few ways you can know what users are visiting your site (hint: without authorization this isn't always possible).