credentials

What Google service account credentials json should be used to sign the URL. This data source checks the following locations for credentials, in order of preference: data source credentials attribute, provider credentials attribute and finally the GOOGLE_APPLICATION_CREDENTIALS environment variable.

NOTE the default google credentials configured by gcloud sdk or the service account associated with a compute instance cannot be used, because these do not include the private key required to sign the URL. A valid json service account credentials key file must be used, as generated via Google cloud console.