Zagreb/Import ZET GTFS
Importing ZET GTFS data is an import of Zagrebački električni tramvaj public transport dataset which is of type GTFS covering Zagreb and surroundings. The import is currently (as of 2020-12-05) at the planning stage.
Goals
Import station IDs to OSM so we can see if our routes have correct station order.
Schedule
The import should go through in December 2020.
Import Data
Background
Data source site: https://www.zet.hr/odredbe/datoteke-u-gtfs-formatu/669
Data license: http://data.gov.hr/otvorena-dozvola
Type of license: Otvorena dozvola
Link to permission: http://imamopravoznati.org/request/dopustenje_za_unos_podataka_iz_g
OSM attribution (if required): https://wiki.openstreetmap.org/wiki/Contributors#City_of_Zagreb
ODbL Compliance verified: yes
Import Type
This is a mostly automated import that uses OSM_Conflator. It will be possible to run it in the future and check if it is still valid. The code used to run OSM Conflator is on Github[1].
Data Preparation
Tagging Plans
Tags that will be put in and conflated:
gtfs:stop_id=* < stop_id from the stops.txt in the GTFS file
official_name=* < stop_name from the stops.txt in the GTFS file
source=Zagrebački električni tramvaj
Changeset Tags
source=Zagrebački električni tramvaj
Data Merge Workflow
Team Approach
The data is pretty straightforward, so Janko Mihelić will do the whole import. A team effort will consist of subsequent entering of public transport routes, and tools which will check the right order of stations in a route. Wrong data in this import will pop up in that phase of GTFS import.
Dedicated user account
The user under which the import will be done is called Import Zet[2].
Workflow
There will be several steps to do the import. OpenStreetMap has one to several public transport stations for each station in the GTFS file. OSM_Conflator can't handle conflating one to many points, so there will have to be several passes. Each time OSM_Conflator will convert one of those stations, and add a gtfs:stop_id=* tag on it. Next time the script is run, it will search for stations without the gtfs:stop_id=* tag, and thus will conflate the second pass. This will continue until Overpass returns no more data.
- Adding gtfs:stop_id=* and official_name=* to all public_transport=platform that don't already have gtfs:stop_id=*, and whose name starts with the same letter as the stop in GTFS data. Do it as many times as you find new stations matched. Each time the .osm changeset file is edited such that all added nodes are deleted, so only those with action="modify" are left.
- Adding gtfs:stop_id=* and official_name=* to all railway=tram_stop that don't already have gtfs:stop_id=*, and whose name starts with the same letter as the stop in GTFS data. Do it as many times as you find new stations matched. Each time the .osm changeset file is edited such that all added nodes are deleted, so only those with action="modify" are left.
QA
There is a tool that already tests public transport routes of Zagrebački električni tramvaj [3]. Until now, it wasn't able to test if the stations were put in in the right order, but now with the IDs, it will be able to. In the same time, it will find if there is a bad ID put in with this import.
See also
The email to the Imports mailing list was sent on YYYY-MM-DD and can be found in the archives of the mailing list at [4].