missing_feed_info_date: GTFS validation rule (feed_info.txt) Warning
Exactly one of feed_start_date / feed_end_date is provided: both should be supplied together.
What the rule checks
Exactly one of feed_start_date / feed_end_date is provided: both should be supplied together.
Severity: warning
A warning marks data the specification allows but that looks doubtful, or recommended information that is missing. The GTFS can still be published, but riders may see the effect, so each case deserves a look.
Where it applies
The rule applies to feed_info.txt. This file describes the dataset itself: its publisher, language and validity period.
Finding and correcting it
Open the GTFS in GTFS Express. Reading is free, and the validation, by the MobilityData validator and the rules of GTFS Express itself, lists the occurrences of missing_feed_info_date with the file and rows involved. The correction is made in a draft, by hand or from a brief, with the licence: the corrected GTFS is validated again before it is delivered, and the change can be undone.
In the MobilityData validator
The MobilityData GTFS validator uses the same code, missing_feed_info_date. Its documentation describes each rule: MobilityData validator rules.