How to run containers as different users in Docker?

Question

linux

Is it possible to run Docker containers as other users than just the user who installed Docker.
After adding a new user to the Docker group, I
sudo usermod -aG docker qwerty
tried running the container on its behalf:
docker run --name test --user qwerty
I got an error:

docker: Error response from daemon: linux spec user: unable to find user qwerty: no matching entries in passwd file.

Answer 1

The usual solution:
Bad practice:

if (!in_array(trim(@$_GET['lang']), $config['langs'])) {

Answer 2

Use default value if 'lang' is not passed in GET string

(!in_array(trim($_GET['lang'] ?? null), $config['langs'])) {

Answer 3

--user - пользователь внутри контейнера.
Чтобы запускать контейнер от пользователя qwerty, надо либо sudo -u qwerty docker run, либо su qwerty, и потом запускать контейнер.