Verifiable Credentials status list sequence

@startuml name "Verifiable Credentials: Status List 2021"

title "Status List issuance process"

autonumber

box "Open edX"
participant     "Trigger Event" as trigger
participant     "Credentials IDA\n(verifiable_credentials)" as credentials
participant     "Public storage" as storage
end box

alt The very first verifiable credential issuance
trigger -> credentials : New verifiable credential issuance requested \n(API "/init/")
rnote over credentials: Check if status index is "0"

else User credential (program certificate) is revoked
trigger -> credentials : Related UserCredential.status has updated
rnote over credentials: Check if status became "revoked"
rnote over credentials: Collect all affected indices

else Service script run
trigger -> credentials : Management command run

end

rnote over credentials: Issue a new Status list \nverifiable credential

credentials -> storage : Publish new Status list version

@enduml