There is only one more required parameter called
t, that is, milliseconds since the 1970 Epoch date (January 1, 1970, at midnight UTC). The epoch date is simply a computer standard used by machines to track time. The easiest thing to do in the NextBus API is to specify
0 for this value that returns data for the last 15 minutes.
There is an optional direction tag that allows you to specify a terminating bus stop in case a route has multiple buses running the route in opposite directions. If we don't specify this, the API will return the first one, which suits our needs. The REST URL to get the Mainline route for the LA Metro looks as follows: http://webservices.nextbus.com/service/publicXMLFeed?command=vehicleLocations&a=lametro&r=2&t=0.
Calling this REST URL in a browser returns...