Using psql in a github action - postgresql

Question

I am trying to use psql in a github action but am seeing the following error:
psql: error: could not connect to server: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
where my github action yml file is shown below (the run_all_tests.sh file just calls a subprocess that tries to run the command psql). Does anyone know why this could be happening?
name: Python application
on:
push:
branches: [master]
pull_request:
branches: [master]
jobs:
build:
runs-on: ubuntu-latest
# Service containers to run with `container-job`
services:
# Label used to access the service container
postgres:
# Docker Hub image
image: postgres
# Provide the password for postgres
env:
POSTGRES_PASSWORD: postgres
# Set health checks to wait until postgres has started
ports:
- 5432:5432
options: >-
--health-cmd pg_isready
--health-interval 10s
--health-timeout 5s
--health-retries 5
steps:
- name: Copy the code
uses: actions/checkout#v2
- name: Set up Python 3.8
uses: actions/setup-python#v2
with:
python-version: 3.8
- name: Install dependencies
run: |
python3 setup.py install
- name: Test with unittest
run: |
cd backend/py
source run_all_tests.sh
env:
# The hostname used to communicate with the PostgreSQL service container
POSTGRES_HOST: postgres
# The default PostgreSQL port
POSTGRES_PORT: 5432

Answer 1

Since I was having the same issue, I tried a different approach that worked for me.
In the first place, I run the job within a container:
jobs:
build:
container: gradle:jdk11
That won't make the psql command available so you need to add a run step to install it. The particular installation method may differ depending on the Docker image you choose:
jobs:
build:
container: gradle:jdk11
...
steps:
- run: |
apt-get update
apt-get install --yes --no-install-recommends postgresql-client
Please note you may have different steps above or below.
Now it's time to execute all these SQL you need. The most important thing here: database hostname is postgres which is the id of the service container.
jobs:
build:
container: gradle:jdk11
...
steps:
- run: |
apt-get update
apt-get install --yes --no-install-recommends postgresql-client
- run: |
psql -h postgres -U postgres -c 'CREATE DATABASE ...'
psql -h postgres -U postgres -c 'CREATE ROLE ...'

Answer 2

Since the job is running directly on a runner machine (not within a docker container), you need to connect to "localhost" instead of "postgres". It should work if you change POSTGRES_HOST: postgres to POSTGRES_HOST: localhost.
This is described in detail in the docs: https://docs.github.com/en/actions/using-containerized-services/creating-postgresql-service-containers