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Ok, so where does it work, and where doesnt it work?

You say if I hit my app URL directly it wont work, then what exactly is the point?

I have an app that requires nothing but the uid of a user to make sure they dont do any action more than once. This is perfect for this model since I never, ever need any more information from them. However if I cant get their UID without them logging in, then its as good as useless.

As an example, I have a link on a group page to my app, when I ported everything o the new code it worked perfectly checking for the canvas_user parameter. the next day that parameter was not being delivered for any reason, from any link, anywhere. Please clarify this before everything goes live and my app still doesnt work.

Did this not make it to the live new Facebook profile? 563113017 11:49, 22 August 2008 (PDT)

Doesn't look like it to me. Of course, my app is still in Developer mode... maybe you don't get it there? --559054607 21:01, 11 October 2008 (PDT)

"Automatic authentication means that if a user visits an application canvas page (whether it's an FBML- or iframe-based canvas page), Facebook will pass that visitor's user ID to the application, even if the user has not agreed to the application's terms of use. With this ID, the application can access the name, friends, and profile picture for most users (except for users who have chosen to not display a public search listing)" You've got be kidding me.. if I haven't agreed to the application's terms of use then it has no right to access ANY of my information. This is blatant data mining without user permission.160800197 09:01, 2 December 2008 (PST)

It's only accessing public search data. If you hide your public search listing, then nothing will be rendered. -- Pete (563683308 10:58, 2 December 2008 (PST))

[edit] So does it work or not?

I read the discussion for Automatic Authentication, and then started debugging. What I seem to be finding is that:

$_REQUEST["fb_sig_canvas_user"] and $fb->get_canvas_user();

both return null unless the user has added my application, even when they are logged in. Am I doing something wrong, or does this simply not work? --1147035171 15:16, 4 February 2009 (PST)

I've brought this up with the engineers. Thanks, Pete (563683308 12:30, 23 February 2009 (PST))

[edit] Does Not Work?

I think this don't work as expected.

If you can specify the problem you're having, I can bring it to the engineers' attention and help troubleshoot your problem. Pete (563683308 12:30, 23 February 2009 (PST))

[edit] Sample code?

I don't get it. This is a little too concise for my liking. I Want to prompt the user to publish results to his feed. And Possibly invite friends. And all this in an iFrame. Can this be done with Automatic Authentication?

No, you can't do these things until the user authorizes your application. Once the user authorizes, you can prompt for extended permissions. Read the Platform Principles and Policies around invites. Pete (563683308 12:04, 28 September 2009 (PDT))

I tried using get_canvas_user() but it resulted in:

  Fatal error: Call to a member function get_canvas_user() on a non-object

I probably have to pass it something, but what? Is there an example code somewhere?

Regards, Florian 1784247695