How to enable zabbix monitoring of postgres running with docker-compose?

Question

PostgreSQL

I recently started learning zabbix. To immediately be "as it should", I decided to configure and install as part of the docker-compose assembly. The local zabbix server and the remote zabbix agent work fine, all data is collected and displayed.
I wanted to further connect the monitoring of the PostgreSQL database, located on the same host as the zabbix server.
Everything is running via docker-compose.
I followed the guide from here: https://habr.com/ru/post/234481/
that is, I took the files from the repository https://github.com/lesovsky/zabbix-extensions/
for the zabbix agent, placed them in the right folder - that's all works, UserParameter'y were added.
Stuck on step:

zabbix-get -s 127.0.0.1 -k pgsql.ping['-h 127.0.0.1 -p 5432 -U postgres -d mydb']

(I left the ip and database name as in the example, I used the correct ones, there are no problems with this).
And the problem is that the zabbix-agent service (from which docker-compose) does not contain psql.
Accordingly, it cannot correctly execute UserParameter "pgsql.ping" , which accesses psql.
The question is how to make it so that psql contained in the db container is called from the zabbix-agent container?
(tried to dig towards /var/run/docker.sock, but never figured out how to be able to execute the OS host program from inside the docker container)

Answer 1

The question is how to make it so that psql contained in the db container is called from the zabbix-agent container?

No way. That's the point of isolating into separate containers. If you need psql in the container with zabbix-agent, then create a custom image from the Dockerfile based on the existing one and install psql there.

Answer 2

I wanted to further connect the monitoring of the PostgreSQL database located on the same host as the zabbix server

If I understand the question correctly, then you need to install zabbix-agent on the host where PostgreSQL is.