aasm

State Machine for Ruby classes.

TODO: https://github.com/aasm/aasm

Class created:

class StateMachine

include AASM

aasm do

state :sleeping, initial: true

state :running, :cleaning

event :run do

transitions from: :sleeping, to: :running

end

event :clean do

transitions from: :running, to: :cleaning

end

event :sleep do

transitions from: [:running, :cleaning], to: :sleeping

end

end

end

Running may commands in the beginning.

2.6.4 :002 > machine = StateMachine.new

=> #<StateMachine:0x00007fedf0531908>

2.6.4 :003 > machine.sleeping?

=> true

2.6.4 :004 > machine.may_run?

=> true

2.6.4 :005 > machine.may_clean?

=> false

2.6.4 :006 > machine.may_sleep?

=> false

Moving to a different state:

2.6.4 :007 > machine.run

=> true

Checking current state:

2.6.4 :014 > machine.aasm.current_state

=> :running

2.6.4 :015 > machine.aasm.current_event

=> :run

2.6.4 :021 > machine.running?

=> true

2.6.4 :022 > machine.cleaning?

=> false

2.6.4 :023 > machine.sleeping?

=> false

May commands:

• May run the one already running.

2.6.4 :028 > machine.aasm.current_state

=> :running

2.6.4 :026 > machine.may_run?

# False because we can't go from running to running.

=> false

2.6.4 :031 > machine.aasm.current_state

=> :running

2.6.4 :032 > machine.may_sleep?

# true because we have a flow from running to sleeping

=> true

Error when not possible:

2.6.4 :034 > machine.run

Traceback (most recent call last):

1: from (irb):34

AASM::InvalidTransition (Event 'run' cannot transition from 'cleaning'.)