@startuml Login

actor User

box "Workstation"
participant Browser
participant Kubectl
participant "Pinniped CLI"
end box

box "Supervisor Cluster"
participant Pinniped as sp
end box

box "Concierge Cluster"
participant Pinniped as wp
end box

box "Corporate Network"
participant "OIDC IDP" as IDP
end box

User -> Kubectl: kubectl get pods
Kubectl -> "Pinniped CLI" : get credential for cluster authentication
"Pinniped CLI" -> "Pinniped CLI": starts localhost listener
"Pinniped CLI" -> User: open browser to URL X
User -> Browser: clicks link
Browser -> sp : ""GET https://supervisor.com/oauth2/authorize""
sp -> Browser: 302 to IDP ""/authorize?redirect_uri=https://supervisor.com/callback""
Browser -> IDP: ""GET /authorize?redirect_uri=https://supervisor.com/callback""
IDP -> IDP: IDP authenticates user
IDP -> Browser: 302 to ""https://supervisor.com/callback""
Browser -> sp: ""GET https://supervisor.com/callback""
sp -> IDP: ""POST /token""
IDP -> sp: access token, ID token, refresh token
sp -> Browser: 302 to ""http://localhost:1234/callback""
Browser -> "Pinniped CLI": ""GET http://localhost:1234/callback""
"Pinniped CLI" -> sp: ""POST https://supervisor.com/oauth2/token""
sp -> sp: lookup auth code
sp -> sp: issue refresh token
sp -> sp: issue ID+access tokens
sp -> "Pinniped CLI": refresh+access+ID tokens
"Pinniped CLI" -> sp: ""POST /oauth2/token"" (w/ access token per RFC8693)
sp -> "Pinniped CLI": cluster-specific ID token
"Pinniped CLI" -> wp: create TokenCredentialRequest (w/ cluster-specific ID token)
wp -> "Pinniped CLI": cluster-specific certificate and key
"Pinniped CLI" -> Kubectl: cluster-specific certificate and key
Kubectl -> wp : ""GET /api/v1/pods""
wp -> wp : Glean user and group information from\ncluster-specific credential
wp -> Kubectl : ""200 OK"" with pods

@enduml
