Added support for the multiprocess library in all unittest runners

* Adds the pathos_multiprocess plugin which serves only to
    install the multiprocess package.  If installed, it will
    be used by all unittest runners instead of the default
    multiprocessing library.

Change-Id: Id18ee56d3fb1466f038aaa8c6fd9e2d890847f9e

cafe/drivers/unittest/runner.py

@@ -20,7 +20,6 @@ import unittest
 import uuid
 from importlib import import_module
 from inspect import isclass
-from multiprocessing import Process, Manager
 from re import search
 from traceback import print_exc
 from cafe.common.reporting import cclogging
@@ -31,6 +30,16 @@ from cafe.drivers.unittest.decorators import (
 from cafe.drivers.unittest.parsers import SummarizeResults
 from cafe.drivers.unittest.suite import OpenCafeUnittestTestSuite
 
+# Support for the alternate dill-based multiprocessing library 'multiprocess'
+# as an experimental workaround if you're having pickling errors.
+try:
+    from multiprocess import Process, Manager
+    sys.stdout.write(
+        "\n\nUtilizing the pathos multiprocess library. "
+        "This feature is experimental\n\n")
+except:
+    from multiprocessing import Process, Manager
+
 
 def tree(directory, padding, print_files=False):
     """

cafe/drivers/unittest/runner_parallel.py

@@ -12,18 +12,26 @@
 # under the License.
 
 from __future__ import print_function
+import sys
+
+# Support for the alternate dill-based multiprocessing library 'multiprocess'
+# as an experimental workaround if you're having pickling errors.
+try:
+    from multiprocess import Process, Queue
+    sys.stdout.write(
+        "\n\nUtilizing the pathos multiprocess library. "
+        "This feature is experimental\n\n")
+except:
+    from multiprocessing import Process, Queue
 
-from multiprocessing import Process, Queue
 from StringIO import StringIO
 from unittest.runner import _WritelnDecorator
 import importlib
 import logging
 import os
-import sys
 import time
 import traceback
 import unittest
-
 from cafe.common.reporting import cclogging
 from cafe.common.reporting.reporter import Reporter
 from cafe.configurator.managers import TestEnvManager

cafe/plugins/pathos_multiprocess/setup.py

@@ -0,0 +1,30 @@
+# Copyright 2015 Rackspace
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+"""
+This plugin installs the pathos multiprocess package.
+Since pathos multiprocess is still in Beta, this plugin is considered
+experimental.
+
+If installed, the cafe unittest runners will use multiprocess instead of
+python's default multiprocessing library.
+"""
+from setuptools import setup
+
+setup(
+    name='cafe_pathos_multiprocess_plugin',
+    version='0.0.1',
+    description='The Common Automation Framework Engine',
+    author='Rackspace Cloud QE',
+    author_email='cloud-cafe@lists.rackspace.com',
+    url='http://rackspace.com',
+    install_requires=['multiprocess'])