Add support for using existing vault auto-auth configurations as the
provider configuration when using Vault's CA provider with AliCloud.
AliCloud requires 2 extra fields to enable it to use STS (it's preferred
auth setup). Our vault-plugin-auth-alicloud package contained a method
to help generate them as they require you to make an http call to
a faked endpoint proxy to get them (url and headers base64 encoded).
Adds support for the approle auth-method. Only handles using the approle
role/secret to auth and it doesn't support the agent's extra management
configuration options (wrap and delete after read) as they are not
required as part of the auth (ie. they are vault agent things).
Adds support for a jwt token in a file. Simply reads the file and sends
the read in jwt along to the vault login.
It also supports a legacy mode with the jwt string being passed
directly. In which case the path is made optional.
Does the required dance with the local HTTP endpoint to get the required
data for the jwt based auth setup in Azure. Keeps support for 'legacy'
mode where all login data is passed on via the auth methods parameters.
Refactored check for hardcoded /login fields.
John Eikenberry