Python code coverage for Doc/includes/mp_workers.py

#	count	content
1	n/a	import time
2	n/a	import random
3	n/a
4	n/a	from multiprocessing import Process, Queue, current_process, freeze_support
5	n/a
6	n/a	#
7	n/a	# Function run by worker processes
8	n/a	#
9	n/a
10	n/a	def worker(input, output):
11	n/a	for func, args in iter(input.get, 'STOP'):
12	n/a	result = calculate(func, args)
13	n/a	output.put(result)
14	n/a
15	n/a	#
16	n/a	# Function used to calculate result
17	n/a	#
18	n/a
19	n/a	def calculate(func, args):
20	n/a	result = func(*args)
21	n/a	return '%s says that %s%s = %s' % \
22	n/a	(current_process().name, func.__name__, args, result)
23	n/a
24	n/a	#
25	n/a	# Functions referenced by tasks
26	n/a	#
27	n/a
28	n/a	def mul(a, b):
29	n/a	time.sleep(0.5*random.random())
30	n/a	return a * b
31	n/a
32	n/a	def plus(a, b):
33	n/a	time.sleep(0.5*random.random())
34	n/a	return a + b
35	n/a
36	n/a	#
37	n/a	#
38	n/a	#
39	n/a
40	n/a	def test():
41	n/a	NUMBER_OF_PROCESSES = 4
42	n/a	TASKS1 = [(mul, (i, 7)) for i in range(20)]
43	n/a	TASKS2 = [(plus, (i, 8)) for i in range(10)]
44	n/a
45	n/a	# Create queues
46	n/a	task_queue = Queue()
47	n/a	done_queue = Queue()
48	n/a
49	n/a	# Submit tasks
50	n/a	for task in TASKS1:
51	n/a	task_queue.put(task)
52	n/a
53	n/a	# Start worker processes
54	n/a	for i in range(NUMBER_OF_PROCESSES):
55	n/a	Process(target=worker, args=(task_queue, done_queue)).start()
56	n/a
57	n/a	# Get and print results
58	n/a	print('Unordered results:')
59	n/a	for i in range(len(TASKS1)):
60	n/a	print('\t', done_queue.get())
61	n/a
62	n/a	# Add more tasks using `put()`
63	n/a	for task in TASKS2:
64	n/a	task_queue.put(task)
65	n/a
66	n/a	# Get and print some more results
67	n/a	for i in range(len(TASKS2)):
68	n/a	print('\t', done_queue.get())
69	n/a
70	n/a	# Tell child processes to stop
71	n/a	for i in range(NUMBER_OF_PROCESSES):
72	n/a	task_queue.put('STOP')
73	n/a
74	n/a
75	n/a	if __name__ == '__main__':
76	n/a	freeze_support()
77	n/a	test()