cscape / wayline-miami

Ⓜ📡 Web server that generates GTFS Realtime data for transit in South Florida

Web server that generates GTFS Realtime Vehicle Positions data for Miami-Dade Transit.

Project Goals

The server should be able to run continuously, serving as both a proxy for the Miami-Dade Transit GTFS as well as provider of GTFS Realtime data. The GTFS-RT data should remain cached in the server memory and refreshed roughly every 25-30 seconds (Google fetches updates every 30secs, other apps may behave the same way). The Miami-Dade Transit GTFS should be fetched hourly and at server start-up.

If the GTFS zip is missing data (like the Coral Gables Trolley, Grand Avenue route) then it's assumed that it doesn't exist and therefore shouldn't be linked, interpolated, or backfilled with guessed data.

Table of Progress

For Trip Updates, we're using TheTransitClock to generate the realtime data from the Vehicle Positions. This is yet to be automated and is still in development. More documentation will follow.

Vehicle Positions

Generated GTFS Realtime data must follow the structure and underlying data types as the MBTA's own GTFS Realtime data, including Long data types where necessary and ensuring everything is consistent.

• All Metrobus locations
• All Metrorail locations
• All Metromover locations
• All Trolley locations - link TSO Mobile (Miami/Doral/Beach/Aventura + other trolleys) data with MDT GTFS
• Coral Gables Trolley - link ETA Transit data with MDT GTFS
• Tri-Rail train locations
• SFRTA connector locations
• Broward County Transit bus locations
• Trolley (Broward) locations - TSO Mobile data
• Palm Tran bus locations
• Trolley (Palm Beach) locations - link TSO data

License

MIT © Cyberscape.

wayline-miami's Issues

VehiclePositions generator loop randomly stops

In production, after a lot of hours, it seems that the recursive function that handles VehiclePositions generation just stops. No apparent reason for it. This causes problems with Interchange.

I'm assuming Node.js is preventing infinite loops (which is technically what this is) and/or the setTimeout isn't firing sometimes.

The request listener for the VehiclePositions feed should trigger generation if the latest feed hasn't been updated in 15+ seconds.

Overlapping VehiclePositions updates

Continuation of #2. This time, there's 2 generators firing at the same time at around the same interval.

Make it so that there's a global register(?) so that the generators fire only one at a time for any given window of time. Might require a check in the exec-vp script.

Should also bump up timeout time to 30 seconds instead of 20.

Web server landing

Maybe this could be used as the background?