Connecting to Postgresql in a docker container from outside

Question

I have Postgresql on a server in a docker container. How can I connect to it from the outside, that is, from my local computer? What setting should I apply to allow that?

Answer 1

You can run Postgres this way (map a port):

docker run --name some-postgres -e POSTGRES_PASSWORD=mysecretpassword -d -p 5432:5432 postgres

So now you have mapped the port 5432 of your container to port 5432 of your server. -p <host_port>:<container_port> .So now your postgres is accessible from your public-server-ip:5432

To test: Run the postgres database (command above)

docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                     NAMES
05b3a3471f6f        postgres            "/docker-entrypoint.s"   1 seconds ago       Up 1 seconds        0.0.0.0:5432->5432/tcp    some-postgres

Go inside your container and create a database:

docker exec -it 05b3a3471f6f bash
root@05b3a3471f6f:/# psql -U postgres
postgres-# CREATE DATABASE mytest;
postgres-# \q

Go to your localhost (where you have some tool or the psql client).

psql -h public-ip-server -p 5432 -U postgres

(password mysecretpassword)

postgres=# \l

                             List of databases
   Name    |  Owner   | Encoding |  Collate   |   Ctype    |   Access privileges
-----------+----------+----------+------------+------------+-----------------------
 mytest    | postgres | UTF8     | en_US.utf8 | en_US.utf8 |
 postgres  | postgres | UTF8     | en_US.utf8 | en_US.utf8 |
 template0 | postgres | UTF8     | en_US.utf8 | en_US.utf8 | =c/postgres   

So you're accessing the database (which is running in docker on a server) from your localhost.

In this post it's expained in detail.