Dumb question from a #Docker noob!

stux⚡

How does one connect to postgresql on the host machine from a docker container?

Since localhost is the container localhost. I tried gateways and even public ip with port but thats baaaad.

Also, for #Channel, this URL needs to point to the public or internal(host machine)?
https://github.com/patchwork-hub/patchwork_dashboard/blob/daf539aa5c921af4a7435db8acb5fe0d2bf5b249/.env.sample#L17
(again localhost = container)

Jorijn Schrijvershof

@stux https://docs.docker.com/desktop/features/networking/#i-want-to-connect-from-a-container-to-a-service-on-the-host

stux⚡

@jorijn hm, this is the compose: https://raw.githubusercontent.com/patchwork-hub/patchwork_dashboard/refs/heads/main/docker-compose.yml

it should be able to reach the internal net right?

Phoenix Gee

@stux basically let pg listen on 0.0.0.0 and map its port to the outside

Jorijn Schrijvershof

@stux I'm not sure what you are trying to accomplish? Does the dashboard service need to connect to postgres on the host?

stux⚡

@phoenixgee Got that! but for the mapping, is it internal:external in https://raw.githubusercontent.com/patchwork-hub/patchwork_dashboard/refs/heads/main/docker-compose.yml ?

stux⚡

@jorijn Yes! It runs a container with the dashboard that needs to connect to masto/post on the host itself

Phoenix Gee

@stux external:internal

Jorijn Schrijvershof

@stux then you should try host.docker.internal:5432

stux⚡

@jorijn Correct

Post is running on host machine on * basically so it /should/ accept but somehow i could not get the connection to outside the container

this shouldn't be hard at all

Jorijn Schrijvershof

@stux it's basic networking under the hood. Have you tried 172.17.0.1?

stux⚡

@jorijn Yup, same result

Todd Knarr

@stux @jorijn Does Postgres have the TCP port enabled? Common configuration is to use a unix socket only, which works for vanilla localhost but doesn't work when you need a real TCP socket to connect to.

Jasper Buma

@stux Hey. Also a n00b here. But you can create custom networks. So both containers can see each other.

My Joplin server has a network just to connect to the postgresql database and one to connect to my Nginx Proxy Manager.

hexaheximal

@stux I don't know if it will work since there's a decent chance that postgres does some magic with SO_PEERCRED but you may also want to look into forwarding over the unix socket, since in theory that would bypass the TCP/IP stack entirely.

Wandering Adventure Party

Dumb question from a #Docker noob!