Collect GTFS-RT data from a Protocol Buffers feed at regular intervals

Usage

rt_collect_protobuf(
  gtfs_rt_url,
  destination_file,
  fields_collect = c("id", "vehicle.trip.trip_id", "vehicle.position.latitude",
    "vehicle.position.longitude", "vehicle.position.speed", "vehicle.timestamp",
    "vehicle.current_status", "vehicle.current_stop_sequence", "vehicle.stop_id"),
  scrape_interval = 60,
  log_file = NA,
  headers = NULL
)

Arguments

gtfs_rt_url: String. URL of the Protocol Buffers GTFS-RT feed.
destination_file: String. File to save the downloaded GTFS-RT data. Content is appended in each iteration.
fields_collect: Character vector. Fields to extract from each entity in the feed.
scrape_interval: Integer (Default 60). Interval in seconds between each download. Negative to run only once.
log_file: String (Optional). Path to a log file to save download logs.
headers: Named list or character vector (Optional). Custom HTTP headers for credentials when accessing the GTFS-RT feed URL.

Value

String. The location of the file where data was collected.

Details

Downloads GTFS-RT data from the specified URL at regular intervals and saves them to the destination file.

This function will run indefinitely until manually stopped (CTRL + C).

Examples

# Create file
destination_file <- withr::local_tempfile(fileext = ".csv")

# Collect data
GTFShift::rt_collect_protobuf(
  gtfs_rt_url = "https://go.tmlmobilidade.pt/hub/api/v1/realtime/vehicles/positions/gtfs.pb",
  destination_file = destination_file,
  scrape_interval = -1 # Negative to run only once
)
#> [2026-07-30 16:12:59] Starting GTFS-RT data collection from https://go.tmlmobilidade.pt/hub/api/v1/realtime/vehicles/positions/gtfs.pb
#> [20260730_161259] Iteration 1 completed
#> [1] "/tmp/Rtmpmh4xWj/file1f28c289041.csv"

# Read data
collection <- read.csv(destination_file)

names(collection)
#>  [1] "id"                            "vehicle.trip.trip_id"         
#>  [3] "vehicle.position.latitude"     "vehicle.position.longitude"   
#>  [5] "vehicle.position.speed"        "vehicle.timestamp"            
#>  [7] "vehicle.current_status"        "vehicle.current_stop_sequence"
#>  [9] "vehicle.stop_id"               "feed_timestamp"               
#> [11] "feed_incrementality"          

head(
  collection |>
    dplyr::select("vehicle.trip.trip_id", "vehicle.position.latitude", "vehicle.position.longitude")
)
#>                   vehicle.trip.trip_id vehicle.position.latitude
#> 1 [07MSC][LA77N]1242_0_1_1630_1659_0_7                   38.8496
#> 2 [07MSC][LA77N]1252_0_3_1700_1729_0_7                   38.7928
#> 3 [07MSC][LA77N]1601_1_2_1600_1629_0_7                   38.7580
#> 4 [07MSC][LA77N]1707_0_1_1630_1659_0_7                   38.7742
#> 5 [07MSC][LA77N]1522_0_1_1700_1729_0_7                   38.7074
#> 6 [07MSC][LA77N]1117_3_2_1630_1659_0_7                   38.7128
#>   vehicle.position.longitude
#> 1                    -9.4395
#> 2                    -9.3736
#> 3                    -9.2268
#> 4                    -9.2305
#> 5                    -9.2257
#> 6                    -9.2754