我可以讓AASM在事件失敗時運行特定的方法嗎？

Question

有沒有一種很好的方法可以告訴AASM，如果在處理任何assm_event時引發異常，我想讓這個錯誤被特定的代碼塊捕獲？

如目前我做這樣的事情

assm_state :state_1 
assm_state :state_2, :before_enter => :validate_something 
assm_state :failed 


assm_event :something_risky do 
    transition :from => :state_1, :to => :state_2 
end 

assm_event :fail do 
    transition :from => [:state_1, :state_2], :to => :failed 
end 

def validate_something 
    begin 
    something_that_might_raise_error 
    rescue 
    self.record_error 
    self.fail 
    end 
end 

什麼，我寧願做是一樣的東西

assm_state :state_1 
assm_state :state_2, :before_enter => :validate_something 
assm_state :failed 


assm_event :something_risky, :on_exception => :log_failure do 
    transition :from => :state_1, :to => :state_2 
end 

assm_event :fail do 
    transition :from => [:state_1, :state_2], :to => :failed 
end 

def validate_something 
    something_that_might_raise_exception 
end 

def log_failure 
    self.record_error 
    self.fail 
end 

，並有如果something_that_might_raise_exception確實提出了一個異常log_failure被調用。理想的情況是我想避免更改AASM所以我很安全的，如果我需要如果你使用它的升級在未來

Answer 1

SimpleStateMachine你可以這樣做：

def something_risky 
    something_that_might_raise_error 
    rescue 
    record_error 
    raise #reraise the error 
    end 
    event :something_risky, :state1 => :state2, 
          RuntimeError => :failed 

Answer 2

我也有這個問題。我有兩件事要做。

1. 按照這個博客的建議http://degenportnoy.blogspot.com/2009/11/event-callbacks-in-aasm.html。
2. 即使您在開發模式下工作，也需要重新啓動應用程序。