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
|
class Master < Concurrent::Actor::RestartingContext
def initialize
# create listener a supervised child of master
@listener = Listener.spawn(name: 'listener1', supervise: true)
end
def on_message(msg)
command, *args = msg
case command
when :listener
@listener
when :reset, :terminated, :resumed, :paused
log(DEBUG) { " got #{msg} from #{envelope.sender}"}
else
pass
end
end
# TODO this should be a part of a behaviour, it ensures that children are restarted/paused etc. when theirs parents are
def on_event(event)
event_name, _ = event
case event_name
when :resetting, :restarting
@listener << :terminate!
when Exception, :paused
@listener << :pause!
when :resumed
@listener << :resume!
end
end
end
class Listener < Concurrent::Actor::RestartingContext
def initialize
@number = (rand() * 100).to_i
end
def on_message(msg)
case msg
when :number
@number
else
pass
end
end
end
master = Master.spawn(name: 'master', supervise: true)
# => #<Concurrent::Actor::Reference:0x7fbedc05e5e0 /master (Master)>
listener = master.ask!(:listener)
# => #<Concurrent::Actor::Reference:0x7fbedd86b840 /master/listener1 (Listener)>
listener.ask!(:number) # => 39
# crash the listener which is supervised by master, it's restarted automatically reporting a different number
listener.tell(:crash)
# => #<Concurrent::Actor::Reference:0x7fbedd86b840 /master/listener1 (Listener)>
listener.ask!(:number) # => 73
master << :crash
# => #<Concurrent::Actor::Reference:0x7fbedc05e5e0 /master (Master)>
sleep 0.1 # => 0
# ask for listener again, old one is terminated with master and replaced with new one
listener.ask!(:terminated?) # => true
listener = master.ask!(:listener)
# => #<Concurrent::Actor::Reference:0x7fbedb929090 /master/listener1 (Listener)>
listener.ask!(:number) # => 72
master.ask!(:terminate!) # => true
sleep 0.1 # => 0
|
