Dockerized Testing with Pytest¶

This setup is based on the Unit Testing in Python Linkedin course.

Docker configuration¶

Dockerfile¶

FROM python:3.7.6-buster

RUN mkdir /pytest_project/
COPY ./test-requirements.txt /pytest_project/
COPY ./setup.py ./setup.py

RUN pip install --upgrade pip
RUN pip install -e .
RUN pip3 install -r /pytest_project/test-requirements.txt

WORKDIR /pytest_project/

CMD "pytest"
ENV PYTHONDONTWRITEBYTECODE=true

docker-compose.yaml¶

version: '3.1'
services:
test:
   build: .
   volumes:
      - .:/pytest_project
   stdin_open: true
   tty: true

Python configuration¶

setup.py¶

from setuptools import setup, find_packages
import os

long_description = '''
This project is an example of a pytest
project featuring assertions,
exceptions, parametrization,
fixtures and factory fixtures.
'''

version = "1.0.0"

requirements = [
]

if __name__ == '__main__':
   setup(
      name='python_unit_testing_in_docker',
      version=version,
      description='Pytest Configuration Example',
      long_description=long_description,
      author="jomeke",
      packages=find_packages(
            exclude=[
               'tests',
            ],
            include=[
               'scripts',
               'utils'
            ],
      ),
      license='MIT',
      install_requires=requirements,
      classifiers=[
         'Development Status :: 1 - Planning',
         'Framework :: Pytest',
         'Intended Audience :: Developers',
         'Intended Audience :: Education',
         'License :: OSI Approved :: MIT License',
         'Programming Language :: Python :: 2',
         'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Topic :: Software Development',
         'Topic :: Software Development :: Libraries',
         'Topic :: Software Development :: Libraries :: Python Modules'
      ],
   )

setup.cfg¶

[metadata]
description-file = README.md

pytest.ini¶

[pytest]
python_paths = scripts
testpaths = tests
addopts = --pep8 --flakes --verbose --durations=10 --color=yes
   --cov=scripts
pep8maxlinelength=100
markers =
   pep8: pep8 style check
   flakes: pyflakes style check

test-requirements.txt¶

coverage==4.5.2
pytest==5.2.0
pytest-cov==2.6.1
pytest-flakes==2.0.0
pytest-pep8
pytest-pythonpath
docker

Usage¶

Build docker image

$ docker-compose build

Run test container

This will run the container and open a bash shell inside the container.

$ docker-compose run test sh

Inside container

Run entire test suite

$ pytest

Run tests from files that match a keyword

$ pytest -k <keyword-to-match-filename>

Run tests while printing all variables and verbose output

$ pytest -vvl

Exit the shell and the test container

$ exit

Discussion¶

Pytest settings could be moved from pytest.ini to setup.cfg. See Pytest Configuration.