credential is used to carry credential data to connect the service.
credential including two parts:
value which devided by
We support following
hmac has two values:
apikey has one value:
file has one value:
file_path, service will decide how to use this file.
env has no values, service will read credential from runtime environment.
base64 has one value:
base64, storage service like gcs will take token files as input, we provide base64 protocol so that user can pass token binary data directly.