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
)
#> [2026-08-27 16:43:56] Starting GTFS-RT data collection from https://go.tmlmobilidade.pt/hub/api/v1/realtime/vehicles/positions/gtfs.pb
#> [20260827_164356] Iteration 1 completed
#> [1] "/tmp/RtmpGgUISp/file1f2163f253a7.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 [F1M13][A2L1N]4704_0_2|2700|1735                   38.7862
#> 2 [F1M13][A2L1N]4600_0_1|2700|1700                   38.6973
#> 3  [0277F][BNA17]2537_0_1|1|3|1740                   38.8657
#> 4 [F1M13][A2L1N]4432_0_1|2700|1740                   38.5262
#> 5 [F1M13][A2L1N]4704_0_2|2700|1720                   38.7069
#> 6 [F1M13][A2L1N]4102_0_2|2700|1740                   38.6809
#>   vehicle.position.longitude
#> 1                    -9.0912
#> 2                    -8.9450
#> 3                    -9.0603
#> 4                    -8.8917
#> 5                    -8.9605
#> 6                    -8.9856