Since we're going to open registration for OpenCF Summit before long and launch what I'm calling our "Engage" application for OpenCF Summit (the name may change), I decided to dig into the Facebook API a bit so we can let people sign in using their Facebook account. We'll also be supporting Twitter and Google sign-ons, but Facebook seemed as good a place as any to start since I saw The Social Network last night (which was completely amazing by the way).
Since the vast majority of my apps at work are behind a firewall this is my first foray into integrating any of the social networks' logins into my own applications. Facebook makes it dead simple to get going, but once I registered my application and tried the login button, I was getting the following error:
API Error Code: 100
API Error Description: Invalid parameter
Error Message: next is not owned by the application.
I did some searching and came up with a bunch of potential solutions that didn't seem to be relevant any longer since the settings they suggested changing don't exist anymore. After a bit of poking around on my application settings on Facebook I noticed my site domain on the Web Site settings tab was blank. I put opencfsummit.org in there (since I'll want the login to apply to all subdomains on that domain), and that resolved the problem for me (see screenshot).
The other thing I was testing with this was to make sure everything worked from Google App Engine, since we may incorporate the Engage app with the main web site, which runs on Open BlueDragon for Google App Engine. I was pleased to see everything worked perfectly, at least so far.
I'm sure some of the other solutions I found will work in other situations, but since none of them seemed to apply for me and this was a fresh application with Facebook's own sample code, I thought someone else might run into this same issue and figured I'd share.