Association Records

Associations are relationships between two schedules (i.e. a main train and an associated train.) Association records are contained within the SCHEDULE data feed, and provide information about the possible associations between train schedules. These can list the service that forms a given schedule and / or the service that a given schedule goes on to form.

For further details, see the Common Interface Format file specification.

Record Layout

Association records are encoded as a JSON hash with a key of "JsonAssociationV1" and a value containing the association data, in the following layout:

JsonAssociationV1:
 transaction_type
 main_train_uid
 assoc_train_uid
 assoc_start_date
 assoc_end_date
 assoc_days
 category
 date_indicator
 location
 base_location_suffix
 assoc_location_suffix
 diagram_type
 CIF_stp_indicator

Example JSON record

 {
   "JsonAssociationV1": {
     "transaction_type": "Create",
     "main_train_uid": "C30123",
     "assoc_train_uid": "C42949",
     "assoc_start_date": "2024-06-03T00:00:00Z",
     "assoc_end_date": "2024-06-21T00:00:00Z",
     "assoc_days": "1111100",
     "category": "NP",
     "date_indicator": "S",
     "location": "YORK",
     "base_location_suffix": null,
     "assoc_location_suffix": null,
     "diagram_type": "T",
     "CIF_stp_indicator": "P"
   }
 }

Association Record Fields

Field	Description
transaction_type	create or delete. A full snapshot file will only contain create records. Daily updates may contain either.
main_train_uid	UID of one train in the association
assoc_train_uid	UID of the other train in the association
assoc_start_date	Start date of the association (in YYMMDD format). In JSON files, this is an ISO8601 format timestamp at UTC.
assoc_end_date	End date for the association (in YYMMDD format). In JSON files, this is an ISO8601 format timestamp at UTC.
assoc_days	A seven-character field; character 1 represents Monday, character 7 represents Sunday. A 1 in a character position means that the service runs on that day, while a 0 means that it does not.
category	The type of association JJ - Join VV - Divide NP - Next This may also be blank (two spaces) to override the permanent value in overlays and cancellations.
date_indicator	Date relationship of the association S - Standard - the association occurs on the same day N - Over next-midnight - the association occurs the next day P - Over previous-midnight - the association occurs the previous day This may also be blank (one space) to override the permanent value in overlays and cancellations.
location	TIPLOC of the location where the association applies
base_location_suffix	Together with the TIPLOC, identifies the event on the base UID
assoc_location_suffix	Together with the TIPLOC, identifies the event on the associated UID
diagram_type	Constant value, "T"
CIF_stp_indicator	STP (short-term planning) schedule indicator C - STP cancellation of permanent association N - New STP association (not an overlay) O - STP overlay of permanent association P - Permanent association