Having written about AASM in the past, first on Chaining state transitions with Acts As State Machine (aasm), and then again in Conditional state transitions with AASM, I thought I had AASM down rather pat.
However, when I tried adding a callback to the aasm_event, I ran into trouble. Quite simply, the callback never worked. Here's the first code:
Notice that the callback registration is in the aasm_event code block. It seemed reasonable that this would be part of the transition. When I determined that this was not working, I had a colleague review the code and we ended up both scratching our heads.
So, I cracked open the library and poked around. I saw the successful aasm_state call displaying the callback registration in the options portion of the method, but the options of the aasm_event were blank. Hmm!
Here are the method definitions for your edification:
aasm_state(name, options={})
aasm_event(name, options = {}, &block)
Well, it was pretty clear how to fix the problem; move the callback registration after the name argument and before the block. Here's the corrected code:
That's it! Have fun.
