Method

I haven't added my app to the Facebook directory or even told anyone about it yet; nevertheless, I somehow wound up with more than 1000 users in my database! (And oddly, Facebook only mentioned 299 "monthly active users"; I wonder how they got that number?)

The app is nowhere near ready, and I don't anyone seeing my plans, since stealing Facebook app ideas is rampant (just look at anything by Zynga)! So I shut it down.

But I still need to develop. And I'd like to let my friends visit, since they'll give me good feedback without causing me trouble. What to do?

Program them in, of course. Read on for my three-step approach.

I was driving home with my middle daughter and a load of groceries; the windows were down, because I don't have air conditioning. Luckily it was a very pleasant day.

As I pulled away from a light, someone bellowed across four lanes and a median, "HIPPY!"

In a split second I considered my options. I discarded the immediate outrage -- C'mon, people, there's a child in a car, must we resort to name calling? -- because I didn't want to turn it into a big problem. Then I realized: I'm a pony-tailed peace-loving man driving an electric car; "hippy" is pretty accurate.

I put my hand out the window and raised a peace sign high.

It wasn't until I was past the intersection that I realized my car has no electric symbols on it anywhere. Either I had just passed a friend with a sense of humor, or someone really wants me to cut my hair.

As I said before, I've had some trouble with PHP Facebook development.. This time, I couldn't get a user ID because the user came from a non-Facebook page.

An application's drawing page is called it's "canvas page". It's the starting point for the whole app. Unfortunately, when the user jumps there from a bookmark, or enters the URL into the browser directly, Facebook can't supply the user ID. The app can't do anything, because it doesn't know who the heck it's working for. The user must visit your app's canvas page from a Facebook page.

Since your canvas page is a Facebook page, and the user just visited it directly, you'd think that redirecting to the same page would do the job. And it does! But only if the user clicks on a link.

Then there's the additional problem of users who don't allow you to see their user ID. You have to ask them for permission first.

I put together a skeleton that takes care of all these issues for FBML pages (I don't think it'll work for iFrame pages). Read on for the code.