SOLVED Nextcloud in a VM and Collabora CODE as an app, cant open documents.

[jagdtigger]

New year, new project(, and OFC new issues).

Despite my best efforts i wasnt able to crack this case so id like to ask for the communities input. The situation as follows:
- Nextcloud is hosted in a VM running ubuntu 22.04.3 LTS, apache2, and mariadb and it is behind haproxy
- collabora code is running as an app on a custom port and with valid ssl certs so no external proxy for it

I already confirmed that the 2 can talk to each other as per this guide and even the webui confirms it can talk to it:

Collabora integration guide

! this is a wiki article - everybody can improve ! Nextcloud integrates functionality to edit office documents online (even collaborative - meaning multiple users can work on the same document at the same time). This integration primarily happens with Collabora Online, but other integrations...

help.nextcloud.com

But id i try to open a document (in this case the default welcome docx) all i get is this error:

Document loading failed
Failed to establish socket connection or socket connection closed unexpectedly. The reverse proxy might be misconfigured, please contact the administrator. For more info on proxy configuration please checkout https://sdk.collaboraonline.com/docs/installation/Proxy_settings.html

Checked nextcloud.log, nothing relevant. So what where should i start looking for clues?

 

[jagdtigger]

I feel so dumb, it never occoured to me that nextcloud wont evaluate the x-forwarded-for header for the WOPI API and i have to add the proxy's IP........