External render failed when content is binary

[NovichekLIS]

Description

Hello . After upgrading to version 1.25.* pandoc stopped working, it returns an error 500.

I tried the command as in the manual.
500 Internal Server Error
An error occurred:

Render, docx render run command pandoc [--from docx --to html --self-contained --template /home/git/gitea/custom/html/basic.html] failed: exit status 63
Stderr: [WARNING] Deprecated: --self-contained. use --embed-resources --standalone
couldn't unpack docx container: not enough bytes

So it is with the recommended updated parameter.
500 Internal Server Error

An error occurred:

Render, docx render run command pandoc [--from docx --to html --embed-resources --template /home/git/gitea/custom/html/basic.html] failed: exit status 63
Stderr: couldn't unpack docx container: not enough bytes

I tried it on different machines, the result is the same

Gitea Version

1.25.1

Can you reproduce the bug on the Gitea demo site?

No

Log Gist

No response

Screenshots

No response

Git Version

git version 2.47.3

Operating System

SMP Debian 4.19.249-2 (2022-06-30) and SMP PREEMPT_DYNAMIC Debian 6.12.48-1 (2025-09-20)

How are you running Gitea?

I use your releases. I use systemd and gitea-1.25.1-linux-amd64.

Database

MySQL/MariaDB

[wxiaoguang]

It seems an error from your external render program?

What if you run that command manually?

[NovichekLIS]

I tried this on the server: "/usr/bin/pandoc --from docx --to html --embed-resources --template /home/git/gitea/custom/html/basic.html test.docx - o out.html " a successful file conversion has occurred. I have been using the gitea + pandoc bundle for more than 5 years and have never had any problems. Additional information on pandoc:
pandoc 3.8
Features: +server +lua
Scripting engine: Lua 5.4

[wxiaoguang]

Can you share your render config in app.ini? Will try to reproduce.

Update: Hmm, reproduced, will take a look.

[wxiaoguang]

Seems to be a regression of Add support for 3D/CAD file formats preview (#34794)

The binary stream corrupts.

[wxiaoguang]

The fix: Fix corrupted external render content #35946

As a workaround, you can use IS_INPUT_FILE=true to bypass the bug (update: might not really work)

[NovichekLIS]

unfortunately, I did not understand how to use a workaround.

[wxiaoguang]

unfortunately, I did not understand how to use a workaround.

Hmm, sorry, it might not really work.

If this bug blocks your daily work, you can safely downgrade to 1.24.7 (or newer) by UPDATE version SET version=321 and use 1.24.7's binary/container image. And then wait for 1.25.2 or later which will contain the bug fix.

🙏

[NovichekLIS]

Unfortunately, rollback to previous versions is not possible due to the update of the database version.
Migration Error: Your database (migration version: 323) is for a newer Gitea, you can not use the newer database for this old Gitea release (321).
I will be waiting for the next version with the hope of a fix.

[wxiaoguang]

Unfortunately, rollback to previous versions is not possible due to the update of the database version.
Migration Error: Your database (migration version: 323) is for a newer Gitea, you can not use the newer database for this old Gitea release (321).

UPDATE version SET version=321, then run the old version.