Docker - usermod: group '1001' does not exist

[Tschrock]

Problem Description

Same issue as #6684 (closed)
If .mitmproxy is owned by a group that exists on the host but not in the docker image (like a secondary user), it will fail to run.

Steps to reproduce the behavior:

1. Create a new user/group on the host: $ adduser james
2. Change .mitmproxy ownership to new user/group: $ chown -R james:james ~/.mitmproxy
3. Try running the docker: $ docker run --rm -it -v ~/.mitmproxy:/home/mitmproxy/.mitmproxy -p 8080:8080 mitmproxy/mitmproxy

Result: usermod: group '1001' does not exist

System Information

Using mitmproxy/mitmproxy:latest, which currently is:
Mitmproxy: 10.3.0
Python: 3.11.9
OpenSSL: OpenSSL 3.2.1 30 Jan 2024
Platform: Linux-6.5.0-28-generic-x86_64-with-glibc2.31

[Prinzhorn]

Any recommendation how to fix that? PRs are welcome. The code is here

mitmproxy/release/docker/docker-entrypoint.sh

Lines 15 to 18 in f05c050

	usermod -o \
	-u $(stat -c "%u" "$f") \
	-g $(stat -c "%g" "$f") \
	mitmproxy

mitmproxy/release/docker/Dockerfile

Line 21 in f05c050

ENTRYPOINT ["docker-entrypoint.sh"]