Add notice for agency_id

[Orkunnnn]

Describe the problem

agency_id is a conditionally required field, and there is no missing_agency_id notice for it. stop_name is also a conditionally required field, and it has its own missing_stop_name notice. Wouldn’t it make sense to have a similar notice for agency_id as well?

Describe the new validation rule

If:
(number_of_agencies > 1) AND (agency_id = '' OR agency_id is missing):
trigger a missing_agency_id notice

Sample GTFS datasets

No response

Severity

ERROR

Additional context

No response

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[skalexch]

Thank you for opening this issue @Orkunnnn. I'll add the notice requirement table.

Notice Requirements

Related spec language	Rationale for rule	Notice name to update or add	Pseudologic	Notice table columns	Severity	Notice description
agency.agency_id, routes.agency_id, fare_attributes.agency_id	agency.agency_id, routes.agency_id or fare_attributes.agency_id` is required when there are multiple agencies.	missing_required_agency	If (number_of_agencies > 1):   For filename in (agency.txt, routes.txt, fare_attributes.txt):    If agency_id = '' OR agency_id is missing: Trigger	filename (agency.txt, routes.txt or fare_attributes.txt), csvRowNumber, agencyName	ERROR	agency.agency_id, routes.agency_id or fare_attributes.agency_id is required when there are multiple agencies.

@emmambd should we also remove the check from missing_required_field since it will have its own notice? Or is that done automatically?

[emmambd]

@skalexch I think @Orkunnnn is pointing out that since agency_id is conditionally required, this is a gap in missing_required_field, unless your investigation showed otherwise, Skander.

[skalexch]

@emmambd you're right. I will also update the logic. agency_id becomes required in agency.txt, routes.txt and fare_attributes.txt