Fintraffic GTFS-RT: FeedEntity.id is not feed-unique

[derhuerst]

Issue description

The many FeedEntity.ids are not unique because they are all "0". This trips tools that use the ID, e.g. to store the entities, even if the feed is not Incrementality = DIFFERENTIAL.

Shell command to reproduce

I'm using `print-gtfs-rt-cli, but also any other Protocol Buffers decoder would work.

curl 'https://mobility-api.mobility-database.fintraffic.fi/gtfs-realtime/v2/' -H "x-api-key: $api_key" -H 'accept: application/protobuf' -fsSL | ~/web/print-gtfs-rt-cli/cli.js -j | jq -rc '.id' | sort | uniq -c
# 1829 0

Reference

id – string, Required, Cardinality One – Feed-unique identifier for this entity. The ids are used only to provide incrementality support. [...]

Last update of GTFS Feed
[e.g. 2019-01-17]

Hash of the GTFS Feed
If you have the ability, please provide a hash of the whole GTFS feed, e.g. a SHA-1 or MD5 hash. This allows others to check if they're working with the exact same version of the feed.

GTFS Feed Download Link

https://mobility-api.mobility-database.fintraffic.fi/gtfs-realtime/v2/