class Synco::Controller
Basic event handling and delegation.
Attributes
Public Class Methods
# File lib/synco/controller.rb, line 24 def self.build(*arguments, **options, &block) controller = self.new(*arguments, **options) if block_given? yield(controller) end controller.freeze return controller end
# File lib/synco/controller.rb, line 36 def initialize @events = Hash.new{|hash,key| hash[key] = Array.new} @aborted = false end
Public Instance Methods
Abort the current event handler. Aborting an event handler persistently implies that in the future it will still be aborted; thus calling try
will have no effect.
# File lib/synco/controller.rb, line 106 def abort!(persistent = false) @aborted = true if persistent throw abort_name end
Fire an event which calls all registered event handlers in the order they were defined. The first argument is used to instance_eval any handlers.
# File lib/synco/controller.rb, line 56 def fire(event, *args) return false unless @events.key?(event) handled = false scope = args.shift @events[event].each do |handler| handled = true if scope scope.instance_exec(*args, &handler) else handler.call end end return handled end
# File lib/synco/controller.rb, line 41 def freeze @events.freeze super end
Register an event handler which may be triggered when an event is fired.
# File lib/synco/controller.rb, line 50 def on(event, &block) @events[event] << block end
Try executing a given block of code and fire appropriate events.
The sequence of events (registered via on
) are as follows:
:prepare
-
Fired before the block is executed. May call
abort!
to cancel execution. :success
-
Fired after the block of code has executed without raising an exception.
:failure
-
Fired if an exception is thrown during normal execution.
:finish
-
Fired at the end of execution regardless of failure.
If abort!
has been called in the past, this function returns immediately.
# File lib/synco/controller.rb, line 85 def try(*arguments) return if @aborted begin catch(abort_name) do fire(:prepare, *arguments) yield fire(:success, *arguments) end rescue Exception => exception # Propagage the exception unless it was handled in some specific way. raise unless fire(:failure, *arguments, exception) ensure fire(:finish, *arguments) end end
Private Instance Methods
The name used for throwing abortions.
# File lib/synco/controller.rb, line 115 def abort_name ("abort_" + self.class.name).downcase.to_sym end