python-jenkins/tests/helper.py
Darragh Bailey a8655eaccc Fix timeout function and add capturing of messages on failure
Ensure process terminate is only called after checking whether the
process is still running so as not to accidentally set an exitcode.
Additionally include improved message exchange and capturing to allow
for easier debug should the expected exceptions not appear on socket
timeouts.

Change-Id: Ic51745ffa67570e9a3ca4574d2bfc54d0cd6724b
2015-08-17 18:09:19 +01:00

76 lines
2.4 KiB
Python

import functools
from multiprocessing import Process
from multiprocessing import Queue
import traceback
from six.moves import socketserver
class TestsTimeoutException(Exception):
pass
def time_limit(seconds, fp, func, *args, **kwargs):
if fp:
if not hasattr(fp, 'write'):
raise TypeError("Expected 'file-like' object, got '%s'" % fp)
else:
def record(msg):
fp.write(msg)
else:
def record(msg):
return
def capture_results(msg_queue, func, *args, **kwargs):
try:
result = func(*args, **kwargs)
except Exception as e:
msg_queue.put(
"Running function '%s' resulted in exception '%s' with "
"message: '%s'\n" % (func.__name__, e.__class__.__name__, e))
# no point re-raising an exception from the subprocess, instead
# return False
return False
else:
msg_queue.put(
"Running function '%s' finished with result '%s', and"
"stack:\n%s\n" % (func.__name__, result,
traceback.format_stack()))
return result
messages = Queue()
# although creating a separate process is expensive it's the only way to
# ensure cross platform that we can cleanly terminate after timeout
p = Process(target=functools.partial(capture_results, messages, func),
args=args, kwargs=kwargs)
p.start()
p.join(seconds)
if p.is_alive():
p.terminate()
while not messages.empty():
record(messages.get())
record("Running function '%s' did not finish\n" % func.__name__)
raise TestsTimeoutException
else:
while not messages.empty():
record(messages.get())
record("Running function '%s' finished with exit code '%s'\n"
% (func.__name__, p.exitcode))
class NullServer(socketserver.TCPServer):
request_queue_size = 1
def __init__(self, server_address, *args, **kwargs):
# TCPServer is old style in python 2.x so cannot use
# super() correctly, explicitly call __init__.
# simply init'ing is sufficient to open the port, which
# with the server not started creates a black hole server
socketserver.TCPServer.__init__(
self, server_address, socketserver.BaseRequestHandler,
*args, **kwargs)