Add kokoro config

.kokoro/common.cfg

@@ -0,0 +1,13 @@
+# Format: //devtools/kokoro/config/proto/build.proto
+
+# Download trampoline resources. These will be in ${KOKORO_GFILE_DIR}
+gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/trampoline"
+
+# All builds use the trampoline script to run in docker.
+build_file: "google-auth-library-python/.kokoro/trampoline.sh"
+
+# Use the Python worker docker iamge.
+env_vars: {
+    key: "TRAMPOLINE_IMAGE"
+    value: "gcr.io/silver-python2/python-worker"
+}

.kokoro/system_tests.cfg

@@ -0,0 +1,16 @@
+# Format: //devtools/kokoro/config/proto/build.proto
+
+# Download secrets from Cloud Storage.
+gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/google-auth-library-python"
+
+# Tell the trampoline which build file to use.
+env_vars: {
+    key: "TRAMPOLINE_BUILD_FILE"
+    value: "github/google-auth-library-python/.kokoro/system_tests.sh"
+}
+
+# Tell the system tests which Google Cloud project to use.
+env_vars: {
+    key: "TEST_PROJECT"
+    value: "python-docs-samples-tests"
+}

.kokoro/system_tests.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# Copyright 2017 Google Inc.
+#
+# 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.
+
+set -eo pipefail
+
+export PATH=${PATH}:${HOME}/gcloud/google-cloud-sdk/bin
+
+cd github/google-auth-library-python
+
+# Unencrypt and extract secrets
+SECRETS_PASSWORD=$(cat "${KOKORO_GFILE_DIR}/secrets-password.txt")
+./scripts/decrypt-secrets.sh "${SECRETS_PASSWORD}"
+
+# Setup gcloud, this is needed for the App Engine system test.
+gcloud auth activate-service-account --key-file system_tests/data/service_account.json
+gcloud config set project "${TEST_PROJECT}"
+
+# Run tests
+tox -e py27-system
+tox -e py36-system

.kokoro/trampoline.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+# Copyright 2017 Google Inc.
+#
+# 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.
+
+python3 "${KOKORO_GFILE_DIR}/trampoline_v1.py"

system_tests/test_compute_engine.py

@@ -17,12 +17,15 @@
 import google.auth
 from google.auth import _helpers
 from google.auth import compute_engine
+from google.auth import exceptions
 from google.auth.compute_engine import _metadata
 
 
 @pytest.fixture(autouse=True)
 def check_gce_environment(http_request):
-    if not _metadata.ping(http_request, timeout=1):
+    try:
+        _metadata.get_service_account_info(http_request)
+    except exceptions.TransportError:
         pytest.skip('Compute Engine metadata service is not available.')