Python development with Docker

In this article we will define and create a docker image which is then ran in docker container.

The example here is intended for local development. This is useful if you want run things on other operating system than you are currently using, for example, using Windows but running Linux environments.

Project structure

.
+-- app
|   +-- <application code>
+-- Dockerfile
+-- docker-compose.yml
+-- requirements.txt

Dockerfile definition

The base Python image can be whatever is suitable for your workload.

How the Dockerfile looks like:

FROM python:3.10-slim-bullseye

WORKDIR /usr/src/app

COPY requirements.txt .
RUN pip install -r requirements.txt

With Docker build and run

Build the image

Then we build the image and name it app-py310.

In this example we build the image in project root where Dockerfile and requirements.txt are located.

docker build -t app-py310 .

Start the container

Then we start a container in interactive mode (bash session) with the previously built image.

docker run -it --name app-py310 --rm --volume ${PWD}:/usr/src/dev app-py310 bash

With Docker compose

Create docker-compose.yml

version: "3"
services:
  app:
    build: .
    stdin_open: true # same as -i
    tty: true        # same as -t
    command: /bin/bash

Build the image

docker-compose build app

Start the container

Here we attach our current directory (${PWD}) to /usr/src/dev so we can modify files locally, but run necessary things in docker.

docker-compose run --volume ${PWD}:/usr/src/dev app