moby/docs/sources/examples/postgresql_service.rst

title

PostgreSQL service How-To

description

Running and installing a PostgreSQL service

keywords

docker, example, package installation, postgresql

PostgreSQL Service

Installing PostgreSQL on Docker

Assuming there is no Docker image that suits your needs in the index, you can create one yourself.

Start by creating a new Dockerfile:

Note

This PostgreSQL setup is for development only purposes. Refer to the PostgreSQL documentation to fine-tune these settings so that it is suitably secure.

postgresql_service.Dockerfile

Build an image from the Dockerfile assign it a name.

$ sudo docker build -t eg_postgresql .

And run the PostgreSQL server container (in the foreground):

$ sudo docker run --rm -P --name pg_test eg_postgresql

There are 2 ways to connect to the PostgreSQL server. We can use working_with_links_names, or we can access it from our host (or the network).

Note

The --rm removes the container and its image when the container exists successfully.

Using container linking

Containers can be linked to another container's ports directly using --link remote_name:local_alias in the client's docker run. This will set a number of environment variables that can then be used to connect:

$ sudo docker run --rm -t -i --link pg_test:pg eg_postgresql bash

postgres@7ef98b1b7243:/$ psql -h $PG_PORT_5432_TCP_ADDR -p $PG_PORT_5432_TCP_PORT -d docker -U docker --password

Connecting from your host system

Assuming you have the postgresql-client installed, you can use the host-mapped port to test as well. You need to use docker ps to find out what local host port the container is mapped to first:

$ docker ps
CONTAINER ID        IMAGE                  COMMAND                CREATED             STATUS              PORTS                                      NAMES
5e24362f27f6        eg_postgresql:latest   /usr/lib/postgresql/   About an hour ago   Up About an hour    0.0.0.0:49153->5432/tcp                    pg_test
$ psql -h localhost -p 49153 -d docker -U docker --password

Testing the database

Once you have authenticated and have a docker =# prompt, you can create a table and populate it.

psql (9.3.1)
Type "help" for help.

docker=# CREATE TABLE cities (
docker(#     name            varchar(80),
docker(#     location        point
docker(# );
CREATE TABLE
docker=# INSERT INTO cities VALUES ('San Francisco', '(-194.0, 53.0)');
INSERT 0 1
docker=# select * from cities;
     name      | location  
---------------+-----------
 San Francisco | (-194,53)
(1 row)

Using the container volumes

You can use the defined volumes to inspect the PostgreSQL log files and to backup your configuration and data:

docker run --rm --volumes-from pg_test -t -i busybox sh

/ # ls
bin      etc      lib      linuxrc  mnt      proc     run      sys      usr
dev      home     lib64    media    opt      root     sbin     tmp      var
/ # ls /etc/postgresql/9.3/main/
environment      pg_hba.conf      postgresql.conf
pg_ctl.conf      pg_ident.conf    start.conf
/tmp # ls /var/log
ldconfig    postgresql