1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
require "celluloid/autostart"
class MyActor
include Celluloid
attr_reader :state
def initialize
@state = :clean
end
def broken_method
@state = :dirty
oh_crap_im_totally_broken
end
end
#
# Using the Supervisor API directly
#
puts "*** Demonstrating using the Supervisor API directly"
# Calling supervise directly returns the supervisor
supervisor = MyActor.supervise
# We can get to the current version of an actor by calling
# Celluloid::Supervisor#actors. This prints ':clean'
puts "We should be in a clean state now: #{supervisor.actors.first.state}"
puts "Brace yourself for a crash message..."
# If we call a method that crashes an actor, it will print out a debug message,
# then restart an actor in a clean state
begin
supervisor.actors.first.broken_method
rescue NameError
puts "Uhoh, we crashed the actor..."
end
puts "The supervisor should automatically restart the actor"
# By now we'll be back in a :clean state!
begin
puts "We should now be in a clean state again: #{supervisor.actors.first.state}"
rescue Celluloid::DeadActorError
# Perhaps we got ahold of the actor before the supervisor restarted it
retry
end
#
# Using the Actor Registry
# This is the preferred approach and will make using DCell easier
#
puts "*** Demonstrating using the actor registry"
# We can give our actor a name and thus avoid interacting with the supervisor
MyActor.supervise as: :my_actor
# Same as above, just getting the actor from a different place
puts "We should be in a clean state now: #{Celluloid::Actor[:my_actor].state}"
puts "Brace yourself for a crash message..."
# If we call a method that crashes an actor, it will print out a debug message,
# then restart an actor in a clean state
begin
Celluloid::Actor[:my_actor].broken_method
rescue NameError
puts "Uhoh, we crashed the actor..."
end
puts "The supervisor should automatically restart the actor"
# By now we'll be back in a :clean state!
begin
puts "We should now be in a clean state again: #{Celluloid::Actor[:my_actor].state}"
rescue Celluloid::DeadActorError
# Perhaps we got ahold of the actor before the supervisor restarted it
# Don't want to catch Celluloid::DeadActorError all over the place? If this
# code were in a supervised Celluloid::Actor itself, the supervisor would
# catch Celluloid::DeadActorError and automatically restart this actor
retry
end
|
