externalProxyDocs: add conf for tus upload

[ScharfViktor]

following this plan I couldn't upload date more than 1mb - fixed it

[Copilot]

Pull Request Overview

This PR enhances the nginx reverse proxy configuration for OpenCloud by adding essential settings for handling file uploads, Server-Sent Events (SSE), and long-running connections.

• Increases client max body size to support file uploads via Tus protocol
• Disables proxy buffering to enable SSE functionality
• Extends timeouts for long-running connections and prevents fallback to alternative upstreams

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[ScharfViktor]

need also adjust collabora config because I get 413 Request Entity Too Large when I try to insert image inside the .odt document

[ScharfViktor]

need also adjust collabora config because I get 413 Request Entity Too Large when I try to insert image inside the .odt document

fixed

[Svanvith]

I will test it, but should we also add a part in the "common issues" section?
Smth like "upload bigger than 1MB failed" and then explain that when you use an external proxy you need to adjust the config?

[ScharfViktor]

I will test it

okay, steps for reproduce

• deploy opencloud with nginx https://docs.opencloud.eu/docs/admin/getting-started/container/docker-compose/external-proxy/
• try to upload file more than 1mb
• create .odt file and try to insert an image more than 1mb in the collabora editor

Expected: it possible to upload file more than 1mb
Actual: getting 413 Request Entity Too Large. my changes fixed it

but should we also add a part in the "common issues" section? Smth like "upload bigger than 1MB failed" and then explain that when you use an external proxy you need to adjust the config?

Yes, that's a good idea. But I would also keep my changes here so that people don't encounter the problem and look for a solution.

[Svanvith]

Tested and approved 👍