Initial Python3 support

Notable Changes:
  -Convert all str types to byte types at cython layer (ascii encoding)
  -Use six for packages that have different names in Python2/Python3
  -By default, unit tests are compiled/run in Python2.7 and Python3.4
  -Ensure MACOSX_BUILD_TARGET is at least 10.7

4 files changed, 37 insertions, 12 deletions

diff --git a/tools/gce/linux_performance_worker_init.sh b/tools/gce/linux_performance_worker_init.sh
index dc4784262e..9b8d1d1eb7 100755
--- a/tools/gce/linux_performance_worker_init.sh
+++ b/tools/gce/linux_performance_worker_init.sh
@@ -69,6 +69,10 @@ sudo apt-get install -y \
   python-pip \
   python-setuptools \
   python-yaml \
+  python3-dev \
+  python3-pip \
+  python3-setuptools \
+  python3-yaml \
   telnet \
   unzip \
   wget \
diff --git a/tools/run_tests/build_python.sh b/tools/run_tests/build_python.sh
index 4cc6881ef5..b1c90df824 100755
--- a/tools/run_tests/build_python.sh
+++ b/tools/run_tests/build_python.sh
@@ -34,6 +34,7 @@ set -ex
 cd $(dirname $0)/../..
 
 TOX_PYTHON_ENV="$1"
+PY_VERSION="${TOX_PYTHON_ENV: -2}"
 
 ROOT=`pwd`
 export LD_LIBRARY_PATH=$ROOT/libs/$CONFIG
@@ -51,11 +52,25 @@ fi
 
 tox -e ${TOX_PYTHON_ENV} --notest
 
+# We force the .so naming convention in PEP 3149 for side by side installation support
+# Note this is the default in Python3, but explicitly disabled for Darwin, so we only
+# use this hack for our testing environment.
+if [ "$PY_VERSION" -gt "27" ]
+then
+  mv $ROOT/src/python/grpcio/grpc/_cython/cygrpc.so $ROOT/src/python/grpcio/grpc/_cython/cygrpc.so.backup || true
+fi
+
 $ROOT/.tox/${TOX_PYTHON_ENV}/bin/python $ROOT/setup.py build
 $ROOT/.tox/${TOX_PYTHON_ENV}/bin/python $ROOT/setup.py build_py
 $ROOT/.tox/${TOX_PYTHON_ENV}/bin/python $ROOT/setup.py build_ext --inplace
 $ROOT/.tox/${TOX_PYTHON_ENV}/bin/python $ROOT/setup.py gather --test
 
+if [ "$PY_VERSION" -gt "27" ]
+then
+  mv $ROOT/src/python/grpcio/grpc/_cython/cygrpc.so $ROOT/src/python/grpcio/grpc/_cython/cygrpc.cpython-${PY_VERSION}m.so || true
+  mv $ROOT/src/python/grpcio/grpc/_cython/cygrpc.so.backup $ROOT/src/python/grpcio/grpc/_cython/cygrpc.so || true
+fi
+
 # Build the health checker
 $ROOT/.tox/${TOX_PYTHON_ENV}/bin/python $ROOT/src/python/grpcio_health_checking/setup.py build
 $ROOT/.tox/${TOX_PYTHON_ENV}/bin/python $ROOT/src/python/grpcio_health_checking/setup.py build_py
diff --git a/tools/run_tests/run_python.sh b/tools/run_tests/run_python.sh
index 7a3ce6b821..8059059d41 100755
--- a/tools/run_tests/run_python.sh
+++ b/tools/run_tests/run_python.sh
@@ -55,3 +55,4 @@ fi
 mkdir -p $ROOT/reports
 rm -rf $ROOT/reports/python-coverage
 (mv -T $ROOT/htmlcov $ROOT/reports/python-coverage) || true
+
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index f7282dddb8..f4582ad3a7 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -374,7 +374,7 @@ class PythonLanguage(object):
   def configure(self, config, args):
     self.config = config
     self.args = args
-    self._tox_env = self._get_tox_env(self.args.compiler)
+    self._tox_envs = self._get_tox_envs(self.args.compiler)
 
   def test_specs(self):
     # load list of known test suites
@@ -386,19 +386,21 @@ class PythonLanguage(object):
       os.path.abspath('src/python/grpcio_health_checking'))
     if self.config.build_config != 'gcov':
       return [self.config.job_spec(
-          ['tools/run_tests/run_python.sh', self._tox_env],
+          ['tools/run_tests/run_python.sh', tox_env],
           None,
           environ=dict(environment.items() +
                        [('GRPC_PYTHON_TESTRUNNER_FILTER', suite_name)]),
-          shortname='py.test.%s' % suite_name,
+          shortname='%s.test.%s' % (tox_env, suite_name),
           timeout_seconds=5*60)
-          for suite_name in tests_json]
+          for suite_name in tests_json
+          for tox_env in self._tox_envs]
     else:
-      return [self.config.job_spec(['tools/run_tests/run_python.sh'],
+      return [self.config.job_spec(['tools/run_tests/run_python.sh', tox_env],
                                    None,
                                    environ=environment,
-                                   shortname='py.test.coverage',
-                                   timeout_seconds=15*60)]
+                                   shortname='%s.test.coverage' % tox_env,
+                                   timeout_seconds=15*60)
+                                   for tox_env in self._tox_envs]
 
 
   def pre_build_steps(self):
@@ -411,7 +413,8 @@ class PythonLanguage(object):
     return []
 
   def build_steps(self):
-    return [['tools/run_tests/build_python.sh', self._tox_env]]
+    return [['tools/run_tests/build_python.sh', tox_env] 
+            for tox_env in self._tox_envs]
 
   def post_tests_steps(self):
     return []
@@ -422,12 +425,14 @@ class PythonLanguage(object):
   def dockerfile_dir(self):
     return 'tools/dockerfile/test/python_jessie_%s' % _docker_arch_suffix(self.args.arch)
 
-  def _get_tox_env(self, compiler):
+  def _get_tox_envs(self, compiler):
     """Returns name of tox environment based on selected compiler."""
-    if compiler == 'python2.7' or compiler == 'default':
-      return 'py27'
+    if compiler == 'default':
+      return ('py27', 'py34')
+    elif compiler == 'python2.7':
+      return ('py27',)
     elif compiler == 'python3.4':
-      return 'py34'
+      return ('py34',)
     else:
       raise Exception('Compiler %s not supported.' % compiler)