version 1 .
embeddedType EntityRef.Cap .

; Asserts that a service should begin (and stay) running after waiting
; for its dependencies and considering reverse-dependencies, blocks,
; and so on.
RequireService = <require-service @serviceName any>.

; Asserts that a service should begin (and stay) running RIGHT NOW,
; without considering its dependencies.
RunService = <run-service @serviceName any>.

; Asserts one or more current states of service `serviceName`. The
; overall state of the service is the union of asserted `state`s.
;
; Only a few combinations make sense:
;  - `started`
;  - `started` + `ready`
;  - `failed`
;  - `complete`
;
ServiceState = <service-state @serviceName any @state State>.

; Possible service states.
State =
/ ; The service has begun its startup routine, and may or may not be
  ; ready to take requests from other parties.
  =started
/ ; The service is ready to take requests from other parties.
  ; (This state is special in that it is asserted *in addition* to `started`.)
  =ready
/ ; The service has failed.
  =failed
/ ; The service has completed execution.
  =complete
.

; Asserts that, when `depender` is `require-service`d, it should not
; be started until `dependee` has been asserted.
ServiceDependency = <depends-on @depender any @dependee ServiceState>.

; Asserts that the service is a "core" service. If *not* specified for
; a service X, where X is not `<milestone Y>` for some Y, the system
; acts as if `<depends-on X <service-state <milestone core> ready>>`
; were asserted.
ServiceMilestone = <core-service @serviceName any>.