Confluent-kafka debian package does not respect already existing users


an installation of confluent-kafka debian package on a system where users cp-kafka and/or cp-kafka-connectalready exists, fails due to not checking if the user is already present.


Preparing to unpack .../confluent-kafka_6.2.7-1_all.deb ...
Unpacking confluent-kafka (6.2.7-1) over (6.2.4-1) ...
Setting up confluent-kafka (6.2.7-1) ...
adduser: The user `cp-kafka' already exists, but is not a system user. Exiting.
dpkg: error processing package confluent-kafka (--configure):
 installed confluent-kafka package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)

Please be advised, that cp-kafka as well as cp-kafka-connect are system user (managed via Ansible). So the above error message is not correct.

It would be nice if package installation would check if the user is already there like it does for the group. Here is a diff with a fix:

diff /var/lib/dpkg/info/confluent-kafka.postinst /var/lib/dpkg/info/
<         adduser --system --disabled-password --disabled-login --home /var/run/kafka \
>       (getent passwd $_user 2>&1 >/dev/null) || adduser --system --disabled-password --disabled-login --home /var/run/kafka \
<         adduser --system --disabled-password --disabled-login --home /var/empty \
>       (getent passwd cp-kafka-connect 2>&1 >/dev/null) || adduser --system --disabled-password --disabled-login --home /var/empty \

I did not find any public source for this package on GitHub cause otherwise I would have already opened an PR.

Is there any chance this fix could land in upstream?