oauth2 for a non-OSM/OHM openstreetmap-website instance fails

[petergboswell@…]

I have a problem with the user-facing way to authenticate JOSM against a non-OSM/OHM openstreetmap-website instance which has basic authentication disabled.

I have oauth2 set up for a Panoramax instance amongst other things so have some understanding of the issues.

My OSM website has a doorkeeper signing key and the JOSM Oauth 2 Appplication is set up in the normal way.

What steps will reproduce the problem?

Clear out JOSM preferences leaving only an oauth.access-token.parameters.OAuth20.https://osm.mysite.net/api' entry for my OSM website

In JOSM Version 19627, download an area and move a node.

Click upload that givies panels saying "Uploading data..." and "Obtain authentication to OSM server"

Click "Yes" and browser opens at my OSM website (osm.mysite.net)

Log in and the page gives the often mentioned "Missing required parameter:client_id" at:

​https://osm.mysite.net/oauth2/authorize?response_type=code&client_id=&redirect_uri=http://127.0.0.1:8111/oauth_authorization&scope=read_gpx%20write_gpx%20read_prefs%20write_prefs%20write_api%20write_notes&state=22da5bc2-e3e1-4b85-a77e-38bba8d20b63&code_challenge_method=S256&code_challenge=Lxtb2JyoY6iCTIj9jzNOxSUzAZSgjROSq02hdT8Cdek

Paste in the OSM website Client ID into the URL and resubmit.

• JOSM gives: "Failed to authenticate at the OSM server '​https://osm.mysite.net/api'. (no token configured)

• Browser gives: "HTTP Error 500: Internal Server Error: org.openstreetmap.josm.data.oauth.OAuth20Exception at the internal server address ​http://127.0.0.1:8111/oauth_authorization?code=p_bohEToJ1l3AOV8G3IAhXlgSB3KS5BxGK160iHX2Ow&state=22da5bc2-e3e1-4b85-a77e-38bba8d20b63

• Rails port console gives: Doorkeeper grant - "token", "p_bohEToJ1l3AOV8G3IAhXlgSB3KS5BxGK160iHX2Ow"

Back in JOSM Preferences, click "Authorise now (Manual)" and enter the token as the Access Token Key.

Clicking "Test Access Token " fails (Failed to access the OSM server '​https://osm.mysite.net/api' with the Access Token 'p_bohEToJ1l3AOV8G3IAhXlgSB3KS5BxGK160iHX2Ow'.The server rejected the Access Token as unauthorised.)

Rails port console now has a second Doorkeeper entry with "token", "06cc923ca6d5a1cb1175bc6a608581b5e394a6dccc7b11119f16a15ceb4be33d"

As expected, nothing has been written to preferences.xml.

JOSM is frozen

Restart JOSM, enter the advanced manual information, click "Authorise now (manual)" and enter the second token.

The second token fails with "Failed to retrieve information about the current user from the OSM server '​https://osm.mysite.net/api')

What is the expected result?

Authentication

What happens instead?

Authenticaion fails

Please provide any additional information below. Attach a screenshot if possible.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2026-09-20 21:33:09 +0200 (Sun, 20 Sep 2026)
Revision:19627
Build-Date:2026-09-21 01:30:50
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (19627 en_GB) Windows 11 64-Bit
OS Build number: Windows 10 Pro 25H2 (26200)
Memory Usage: 712 MB / 16328 MB (433 MB allocated, but free)
Java version: 18.0.1.1+2-6, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Look and Feel: com.sun.java.swing.plaf.windows.WindowsLookAndFeel
Screen: \Display0 1920x1080x32bpp@60Hz (scaling 1.00×1.00)
Maximum Screen Size: 1920×1080
Best cursor sizes: 16×16→32×32, 32×32→32×32
System property file.encoding: UTF-8
System property sun.jnu.encoding: Cp1252
Locale info: en_GB
Numbers with default locale: 1234567890 -> 1234567890

Plugins:
+ ImportImagePlugin (36503)
+ PicLayer (275)
+ apache-commons (36483)
+ ejml (36483)
+ geotools (36483)
+ imagery_offset_db (36503)
+ jackson (36502)
+ jaxb (36483)
+ jts (36483)
+ mbtiles (v2.8.1)
+ photo_geotagging (36503)
+ photoadjust (36503)

Last errors/warnings:
- 00000.372 W: extended font config - overriding 'filename.Myanmar_Text=mmrtext.ttf' with 'MMRTEXT.TTF'
- 00000.373 W: extended font config - overriding 'filename.Mongolian_Baiti=monbaiti.ttf' with 'MONBAITI.TTF'
- 00002.023 W: Update plug-ins - You updated your JOSM software. To prevent problems the plug-ins should be updated as well.  Update plug-ins now?

OSM API: https://osm.mysite.net/api