pg_service.conf + psycopg2 example

Dockerfile

FROM python:3-alpine

# install requirements for psycopg2
RUN apk update && apk add -u \
    postgresql-dev \
    gcc \
    python3-dev \
    musl-dev

RUN pip3 install psycopg2

ENV PGSYSCONFDIR=/usr/etc/postgresql
ADD pg_service.conf /usr/etc/postgresql/pg_service.conf

WORKDIR /app
ADD example.py /app

CMD ["python3", "example.py"]

example.py

#!/usr/bin/env python3

import psycopg2


def service_details():
    con = psycopg2.connect(service='example')
    cur = con.cursor()
    cur.execute('select version() as version '
                ', current_database() as db '
                ', current_user as user '
                ', now()::text as query_time '
                )
    result = cur.fetchone()
    return result

if __name__ == '__main__':
    x = service_details()
    print(x)

pg_service.conf

[example]
host=warehouse.pgdata.xyz
dbname=warehouse
port=5433
user=etl_user

Result.txt

$ docker build -t pgexample .
$ docker run -e PGPASSWORD=XXXXXXX pgexample

('PostgreSQL 9.4.4 on x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu 4.8.2-19ubuntu1) 4.8.2, 64-bit', 'warehouse', 'etl_user', '2016-07-13 17:41:30.739065+00')