test(logging): add kokoro build script for environment tests (#3812)

* test(logging): add kokoro build script for environment tests

internal/kokoro/environment.sh

@@ -0,0 +1,75 @@
+#!/bin/bash
+# Copyright 2021 Google LLC
+#
+# 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.
+
+# A suite of tests offered by https://github.com/googleapis/env-tests-logging
+# That allows deploying and testing features in live GCP services.
+# Currently only configured to test logging & error reporting
+
+set -eo pipefail
+
+# Test prechecks
+if [[ -z "${ENVIRONMENT:-}" ]]; then
+  echo "ENVIRONMENT not set. Exiting"
+  exit 1
+fi
+
+if [[ -z "${PROJECT_ROOT:-}"  ]]; then
+    PROJECT_ROOT="github/google-cloud-go"
+fi
+
+# Add the test module as a submodule to the repo.
+cd "${KOKORO_ARTIFACTS_DIR}/github/google-cloud-go/internal/"
+git submodule add https://github.com/googleapis/env-tests-logging
+cd "env-tests-logging/"
+
+# Disable buffering, so that the logs stream through.
+export PYTHONUNBUFFERED=1
+
+# Debug: show build environment
+env | grep KOKORO
+
+# Set up service account credentials
+export GOOGLE_APPLICATION_CREDENTIALS=$KOKORO_KEYSTORE_DIR/72523_go_integration_service_account
+gcloud auth activate-service-account --key-file=$GOOGLE_APPLICATION_CREDENTIALS
+
+set -x
+export PROJECT_ID="dulcet-port-762"
+gcloud config set project $PROJECT_ID
+gcloud config set compute/zone us-central1-b
+
+# Authenticate docker
+gcloud auth configure-docker -q
+
+# Install nox
+python3 -m pip uninstall --yes --quiet nox-automation
+python3 -m pip install --upgrade --quiet nox
+python3 -m nox --version
+
+# create a unique id for this run
+UUID=$(python  -c 'import uuid; print(uuid.uuid1())' | head -c 7)
+export ENVCTL_ID=ci-$UUID
+echo $ENVCTL_ID
+
+# Run the specified environment test
+set +e
+nox --python 3.7 --session "tests(language='go', platform='$ENVIRONMENT')"
+TEST_STATUS_CODE=$?
+
+# destroy resources
+echo "cleaning up..."
+./envctl/envctl go $ENVIRONMENT destroy
+
+# exit with proper status code
+exit $TEST_STATUS_CODE