Establish session - for Backend Services this means getting a token.
Revoke session - clear cached token.
Fetch wrapper that adds Bearer token authorization. Automatically obtains token on first request and retries once on 401.
Optionalinit: RequestInit
SMART Backend Services authentication provider.
Implements OAuth 2.0 client_credentials grant with JWT bearer assertion for server-to-server authentication per SMART Backend Services spec.
See
https://hl7.org/fhir/smart-app-launch/backend-services.html