zacs / ha-gtfs-rt

Real-time transit information for Home Assistant
MIT License
69 stars 29 forks source link

Montréal STM agency only publish partial updates #38

Open mguaylam opened 9 months ago

mguaylam commented 9 months ago

The Montréal agency (STM) only publish partial updates in their GTFS-RT feed.

Consequence: some trips will disappear in an update and reappear in the next one. After talking to their data analyst, they do this to make the API lighter, they will only publish data that has changed in the source system (I find this explanation hard to believe as I found the updates quite arbitrary). But this has the effect of trips disappearing for short times since it does not retain trips and start with a clean sheet when pulling new data.

Here’s the effect observed : next trip --> the trip after --> next trip --> the trip after Here’s a visual representation : image

How can we handle this issue? Would it be by retaining trips? Thank you for your help.