Dokker

Development

This is a development version of the package. Its API is not stable and might change at any time.

Inspiration

This package is designed to manage docker compose projects programmatically via python.

It provides a simple way to create, start, stop, and remove docker compose projects, as well as a way to interact with the containers and services within the project ( like running commands,).

While other packages exist that provide similar functionality (e.g. python-on-whales, testcontainers, etc.), dokker focusses on interacting with the docker compose project asyncronously (using asyncio, but with sync apis).

This allows for patterns like inspecting the logs of a container while your python code is interacting with it.

The primary use case for this package is to create integration tests for docker compose projects. It easily integrates with pytest.

Installation

pip install dokker

Sync Usage

Imaging you have a docker-compose.yaml file that looks like this:

version: "3.4"

services:
  echo_service:
    image: hashicorp/http-echo
    command: ["-text", "Hello from HashiCorp!"]
    ports:
      - "5678:5678"

To utilize this project in python, you can use the local function to create a project from the docker-compose.yaml file. (you can also use other builder functions to create projects from other sources, e.g. a cookiecutter template)

from dokker import local, HealthCheck
import requests

# create a project from a docker-compose.yaml file
deployment = local(
    "docker-compose.yaml",
    health_checks=[
        HealthCheck(
            service="echo_service",
            url="http://localhost:5678",
            max_retries=2,
            timeout=5,
        )
    ],
)
deployment.health_on_enter = True  # optional: wait for all health checks to be successful on enter

watcher = deployment.logswatcher(
    "echo_service", wait_for_logs=True, 
)  # Creates a watcher for the echo_service service, a watcher
# will asynchronously collect the logs of the service and make them available

# start the project (), will block until all health checks are successful
with deployment:
    # interact with the project

    with watcher:

        # interact with the project
        print(requests.get("http://localhost:5678"))

        # as we set wait_for_logs=True, the watcher will block until the logs are collected

    print(watcher.collected_logs)
    # interact with the project

Async Usage

from dokker import local

# create a project from a docker-compose.yaml file
deployment = local("docker-compose.yaml")
deployment.up_on_enter = False # optional: do not start the project on enter

# start the project ()
async def main()
    async with deployment:
        # interact with the project
        await deployment.aup() # start the project (and detach)


        async with deployment.logwatcher("service_to_log", log=print):
            await deployment.arestart("service_to_log") # restart the service

        

asyncio.run(main())

Pytest Usage

import pytest
from dokker import local

@pytest.fixture(scope="session")
def deployment():
    deployment = local("docker-compose.yaml")
    deployment.health_on_enter = True
    with project:
        yield project