Dependencies:

node.js

To run:

clone the project

`npm install`

`node index.js`

The majority of the program logic is in index.js

Currently, the gtfs-realtime specification only allows clients to download the data of the entire fleet of vehicles at once.

The main use for this application is to support mobile apps, where users may be wary of bandwidth consumption.  
With some gtfs-realtime vehicle position files having sizes of >50kb, the bandwidth requirements can stack up very quickly when constantly updating vehicle positions.
This application will allow clients to request only the data they need, moving the bandwidth cost to a middleman server, rather than the client.

Usage: Change feedUrl to the relevant feed.
To request data:
http://yourhost.whatever:3000/:search_by/:query/:ret_vals

:search_by is the variable which you want to search through
    the tree structure is navigated using "."
:query is what the variable must equal in order for the vehicle to be considered
:ret_vals are the variables which you want returned
    ret_vals can be seperated by "," and the tree structure can be navigated using "."
    if no ret_vals are defined, it will default to longitude, latitude, and bearing.

eg- http://yourhost.whatever:3000/trip.route_id/32/position.longitude,position.latitude,stop_id
This would return the longitude, latitude, and stop_id of any vehicle currently on route_id 32.

For gtfs-realtime specifications, go to https://developers.google.com/transit/gtfs-realtime/
In order to view the tree structure easily in json format, uncomment the "out=entities" line in processQuery().