Class: LoadTest::Future

Inherits:
Object
  • Object
show all
Defined in:
lib/load_test/future.rb

Overview

Make parallelism by processes manageable.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(&block) ⇒ Future

Execute the processing of the block asynchronously.



23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
 
# File 'lib/load_test/future.rb', line 23

def initialize(&block)
  reader, writer = IO.pipe

  @pid = fork do
    reader.close
    begin
      result = block.call
    rescue => e
      result = e
    end
    Marshal.dump(result, writer)
  end
  writer.close

  @reader = reader
  @is_done = false
end

Instance Attribute Details

#pid ⇒ Object (readonly)

process id



4
5
6
 
# File 'lib/load_test/future.rb', line 4

def pid
  @pid
end

#reader ⇒ Object (readonly)

reader of IO.pipe



6
7
8
 
# File 'lib/load_test/future.rb', line 6

def reader
  @reader
end

Class Method Details

.all(futures) ⇒ Object

Wait until all futures have completed.



17
18
19
 
# File 'lib/load_test/future.rb', line 17

def all(futures)
  futures.each(&:wait)
end

.race(futures) ⇒ Object

Get the first completed future.



10
11
12
13
14
 
# File 'lib/load_test/future.rb', line 10

def race(futures)
  hash = futures.to_h { [_1.reader, _1] }
  readers, = IO.select(futures.map(&:reader))
  hash[readers[0]]
end

Instance Method Details

#abort ⇒ Object

Abort the future.



59
60
61
62
63
 
# File 'lib/load_test/future.rb', line 59

def abort
  Process.kill(:INT, @pid)
  @reader.close
  @is_done = true
end

#take ⇒ Object

Wait until the process is completed and return the result.



50
51
52
53
54
55
56
 
# File 'lib/load_test/future.rb', line 50

def take
  wait
  result = Marshal.load(@reader)
  @reader.close
  raise result if result.is_a?(Exception)
  result
end

#wait ⇒ Object

Wait for the process to complete.



42
43
44
45
46
47
 
# File 'lib/load_test/future.rb', line 42

def wait
  return if @is_done
  Process.waitpid(@pid)
  @is_done = true
  self
end