import os

import sys

from gcloud import datastore

# Defaults from shell environ. May be None.

DATASET_ID = os.getenv('GCLOUD_TESTS_DATASET_ID')

CLIENT_EMAIL = os.getenv('GCLOUD_TESTS_CLIENT_EMAIL')

KEY_FILENAME = os.getenv('GCLOUD_TESTS_KEY_FILE')

DATASETS = {}

ENVIRON_ERROR_MSG = """\

To run the regression tests, you need to set some environment variables.

Please check the Contributing guide for instructions.

"""

def get_environ():

if DATASET_ID is None or CLIENT_EMAIL is None or KEY_FILENAME is None:

print >> sys.stderr, ENVIRON_ERROR_MSG

sys.exit(1)

return {

'dataset_id': DATASET_ID,

'client_email': CLIENT_EMAIL,

'key_filename': KEY_FILENAME,

}

def get_dataset():

environ = get_environ()

get_dataset_args = (environ['dataset_id'], environ['client_email'],

environ['key_filename'])

if get_dataset_args not in DATASETS:

# Cache return value for the environment.

DATASETS[get_dataset_args] = datastore.get_dataset(*get_dataset_args)

return DATASETS[get_dataset_args]