• Working with GTFS files
  • Implementation details

Working with GTFS files

The core module provides a way to work with GTFS files as described by the standard. The file is accessed wrapped within a Resource to ensure it is released properly when done working with it. This API lives in the com.mobimeo.gtfs.file package

import com.mobimeo.gtfs.file._

import fs2.io.file.Path

import cats.effect._
import cats.effect.unsafe.implicits.global

GtfsFile[IO](Path("site/gtfs.zip")).use { gtfs =>
  IO.pure(s"Some work with the GTFS file at ${gtfs.file}")
}.unsafeRunSync()
// res0: String = "Some work with the GTFS file at site/gtfs.zip"

Within the use scope you can use the gtfs reference to read from and write to the file. To achieve this, have a look at the dedicated pages:

• Reading from a GTFS file
• Writing to a GTFS file

Implementation details

The GtfsFile class is implemented in a way that doesn’t require to load the entire GTFS file into memory. The zip file is mapped to a FileSystem and files are accessed through this API, under the hood. Reading a CSV file from the GTFS data, streams the content, by default only loading in memory what is necessary to process the current CSV row.

The class is also implemented in a way that makes it possible to modify files in place, even though it is recommended to work on a copy.