I have a use-case where I want to use OIDC based access token (jwt token) for authorizing VAULT APIs instead of the client token.
In current state, getting a VAULT client token from oidc token is possible only through UI standard flow. But if VAULT API needs to be called from some batch job or a workflow; where no UI is involved, generating Vault token through OIDC token is not possible.
Can there be a support of passing “Authorization” header with “Bearer <access_token>” instead of the current <vault_client_token>.
OR if there’s already some way like this, please suggest
You can only authenticate to Vault directly using a Vault Token.
The authentication methods are there to facilitate you a road to authenticate and authorise using any (external) system.
Letting Vault having to figure out what kind of token is being sent, for what system, with what restrictions, etc. would be a complete mess.
From what you have said it is more likely that you want to use the JWT authentication method.