# Requests and responses are ordinary records selected by both participants.
# The `By` checks and exact RecordLink relation are application policy.
datalog {
  request(R) :- Have(R), Field(R,'Group',_,'request-response'), Field(R,'App',_,'request-response/request'), Field(R,'By',_,'{{CLIENT_KEY}}').
  response_for(E,R) :- Have(E), Field(E,'Group',_,'request-response'), Field(E,'App',_,'request-response/response'), Field(E,'By',_,'{{SERVICE_KEY}}'), RecordLink(E,'+Link',_,'request',R), request(R).
  SelectStoredRecord(R) :- request(R).
  ExposeRecord(R) :- request(R).
  SelectAdvertisedCandidate(R) :- Advertised(R), AdvertisedField(R,'Group',_,'request-response'), AdvertisedField(R,'App',_,'request-response/request'), AdvertisedField(R,'By',_,'{{CLIENT_KEY}}').
  SelectStoredRecord(E) :- response_for(E,_).
  ExposeRecord(E) :- response_for(E,_).
  SelectAdvertisedCandidate(E) :- Advertised(E), AdvertisedField(E,'Group',_,'request-response'), AdvertisedField(E,'App',_,'request-response/response'), AdvertisedField(E,'By',_,'{{SERVICE_KEY}}').
}