d11wtq/postgres repository overview

⁠PostgreSQL Docker Container

This is a docker container for PostgreSQL 9.3. It is designed to be configurable with ease and to allow for persistent storage on the host (optional).

The default configuration is intentionally minimal.

⁠Testing

Without any special configuration, you should be able to start the container and connect to it on port 5432.

-bash$ docker run -d -p 5432:5432 d11wtq/postgres
abcdef1234567890abcdef1234567890abcdef1234567890ab

-bash$ nc -z localhost 5432
Connection to localhost port 5432 [tcp] succeeded!

A more complete test can be done by testing the server-client interaction:

-bash$ docker run -d --name server d11wtq/postgres
abcdef1234567890abcdef1234567890abcdef1234567890ab

-bash$ docker run -ti \
>   --link server:server \
>   -e PGPASSWORD=postgres \
>   d11wtq/postgres \
>   psql -h server -U postgres

psql (9.3.5)
Type "help" for help.

postgres=#

⁠Configuration

The container runs postgres in the foreground under a user called 'postgres'. The data directory is stored at /postgres/data, and a minimal postgresql.conf is stored in the data directory.

The 'postgres' user is the superuser and has the password 'postgres'.

For convenience, there is an empty database called 'default' and a user 'default' with password 'default' that has full privileges on this database (but not any others). It is advised to use this for application integration.

The default pg_hba.conf allows connections from any user on any host provided they have the MD5 password.

#     database  user  source  auth
host  all       all   all     md5

To adjust the configuration of postgres, you can add *.conf files to /postgres/conf.d/, either by mounting a volume, or by using this image as a base image. If you have any need to change pg_hba.conf or pg_ident.conf, specify their locations in here.

The data directory is lazily initialized on container startup, unless it is already initialized. This allows you to mount /postgres/data as a volume if you need long-lived persistence on the host.

Logs are written to stdout and stderr.

⁠Example Usage

⁠Server

The following runs postgres, keeping the data directory on the host and supplying configuration to adjust the default search_path.

-bash$ docker run -d \
>   --name postgres \
>   -v $(pwd)/data:/postgres/data \
>   -v $(pwd)/conf.d:/postgres/conf.d \
>   d11wtq/postgres
abcdef1234567890abcdef1234567890abcdef1234567890ab
-bash$

The shared volume conf.d/ contains a file named 'search_path.conf' with the contents:

search_path = '"$user", public'

The shared volume data/ is initially empty, but will be initialized by the container.

⁠Client Access

If you need to try something in the psql client, the intended way to do this is to use two containers in a client-server setup. Start the server container with a name, then start a second container linking to that name, but running 'bash', or 'psql' instead of the default server startup script.

Connecting a client to the above server would look like this:

-bash$ docker run -ti \
>   --link postgres:server \
>   d11wtq/postgres \
>   psql -h server -U default
Password:

psql (9.3.5)
Type "help" for help.

default=>

If you really want to work in a single container, you can run /usr/local/bin/start_postgres from a bash shell in the container. Press Ctrl-C to stop the server.