Provides Golang structs generated from the GTFS-realtime Protocol Buffer specification. These structs will allow you to parse a binary Protocol Buffer GTFS-realtime data feed into Golang objects.
To use the gtfs-realtime-bindings
structs in your own project, you need to
first install this library with:
go get github.com/google/gtfs-realtime-bindings/golang/gtfs
And install the golang protobuf library dependency with:
go get github.com/golang/protobuf/proto
The following code snippet demonstrates downloading a GTFS-realtime data feed from a particular URL, parsing it as a FeedMessage (the root type of the GTFS-realtime schema), and iterating over the results.
package main
import (
"fmt"
proto "github.com/golang/protobuf/proto"
"github.com/google/gtfs-realtime-bindings/golang/gtfs"
"io/ioutil"
"log"
"net/http"
)
func main() {
var (
username = "YOUR_ACCESS_KEY"
password = "YOUR_SECRET_KEY"
)
client := &http.Client{}
req, err := http.NewRequest("GET", "URL OF YOUR GTFS-REALTIME SOURCE GOES HERE", nil)
req.SetBasicAuth(username, password)
resp, err := client.Do(req)
defer resp.Body.Close()
if err != nil {
log.Fatal(err)
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Fatal(err)
}
feed := gtfs.FeedMessage{}
err = proto.Unmarshal(body, &feed)
if err != nil {
log.Fatal(err)
}
for _, entity := range feed.Entity {
tripUpdate := entity.TripUpdate
trip := tripUpdate.Trip
tripId := trip.TripId
fmt.Printf("Trip ID: %s\n", *tripId)
}
}
For more details on the naming conventions for the Golang structs generated from the gtfs-realtime.proto, check out the Golang Generated Code section of the Protocol Buffers developer site.