Unit testing Google's Cloud Storage API

Question

I have an API endpoint I\'m trying to write unit tests for and I can\'t seem to figure out how to unit test the Python Google Cloud Storage client library calls (https://cloud.g

Answer 1

The list of available unit test does not list GCS. You can file a feature request on their GitHub to add that functionality.

In the mean time using the setUp for your tests to create files is probably your best bet.

Answer 2

Since we have been bitten by severalGoogle API transistions so far (blobstore, blobstore with gs:/, cloudstorage, google-clound-storage) we have long created our own thin wrapper around all GCS access. This also includes stubbing for tests, like this:

def open(path, mode='w', bucket=None, content_type=None):
    if not bucket:
        bucket = app_identity.get_default_gcs_bucket_name()
    jsonpath = '/{}'.format(os.path.join(bucket, path))
    jsonpath = jsonpath.replace('*', str(datetime.date.today()))

    if os.environ.get(b'GAETK2_UNITTEST'):
        LOGGER.info('running unittest, GCS disabled')
        return StringIO()

    return cloudstorage.open(jsonpath, mode, content_type=content_type)

Still a lot of work if you want to retrofit that on a big application. But might be worth it - the next Google API depreciation will come.