Allow users to specify p12/json credentials file #638
Description
From the conversation in #621
What is the process to specify the keyfile path? That is, I know my keys are at "/creds.json" or "/key.p12" (pick whichever you want) and don't want to use the environment variable stuff...
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It does not exist ATM.
We need to make sure that people can still be explicit. So the goal of this bug is to make sure people can specify a path to either a .p12 file or a .json file with credentials, and use all the services with those credentials...