Docker Compose

Docker Compose is a tool to manage multi-container docker applications running on a single host just by configuring a YAML file. it allows the management of multiple docker isolated environments, networks, and information volumes.

Docker Compose is a good fit for single-host deployment, development, and automated testing environments. PaaS, SaaS, and IaaS providers like; Heroku, Amazon Web Services, and Digital Ocean, among others, encourage its usage for local development.

The Architectural Journey

This chapter analyzes Docker Compose from an architectural perspective; Exploring source code, documentation, and people interaction.

Our journey will start at sea level, looking into the product vision. From there, we do a full descent, traveling to architecture, going deeper into code, and at 10.000 meters depth analyze configuration, collaboration, sustainability, and any insightful discovery during this journey.

Team

  • Andrea Nardi
  • Kanya Paramita Koesoemo
  • L.C Guerchi
  • Manisha Sethia

Contributions

Fix configuring labels when using Buildkit environment
docker/compose
This is our first pull request, we debug the issue of when adding label to a Docker container on its image is not working when using buildkit (CLI) mode. After debugging, we found out that it was because of missing line of code adding labels parameter to the builder inside _CLIBuilder function. It took a lot of time to debug because we need to figure out the code flow which was quite harder than we thought. Finally, we found out that we only have to add 1 line of code. Here in the PR we communicate with the Compose developers where we consult whether it's better for us to create the test as well for this case.
closed
Open PR
Fix docker-compose with buildkit not inserting container labels
docker/compose
Since the first PR was too complicated because of the commits, we decided to make a new PR instead. Here we made a contribution to a Docker-Compose repository. The PR fixes the problem of missing labels in Docker containers built with the buildkit feature. We also add an integration test for the case where we create a service with CLI mode and add labels as parameter thus we test the image whether or not its containing label configuration. It took quite some time to figure out how the tests are structured and how it works. The most challenging part is figuring out the data structure and what to assert. The whole test result itself is quite flaky and took some time to execute.
merged
Open PR
Add Integration Test for Build CLI with buildparams, target and cache from parameters
docker/compose
While trying to resolve the bug issue, we come up with an idea of adding more integration test for other paramteres in building the service through CLI mode. We choose to add integration test for build args, target and cache from parameters. Main effort was again in figuring out how the test should be organized and how to assert.
open
Open PR

What is Docker Compose, and why does it matter?

Docker Compose is an orchestration tool that manages multiple docker containers in a single application, allowing the running of application components in isolated environments without unnecessary complexities. Compose automates the building, deploying and running of the docker containers allowing engineers to develop and deploy without building, dependencies, and compatibility issues. Compose achieves such isolation using container-based technology which allows a lower CPU and memory overhead compared to hypervisors and virtual machines.

Docker Compose
Mar 2, 2020

Relevant Architectural Views

Docker Compose is a lightweight orchestration tool for deploying multi-container applications on a single host machine; it easy to use for Docker users, and does not require extensive configuration.

Docker Compose
Mar 19, 2020

Quality and Technical Debt

We analyze the integration process, code quality, test coverage, and how this is facilitating the roadmap of Compose. Then, we delve a bit deeper into technical debt and refactoring solutions of newer features and the entire system as a whole. Overall, Compose system has an organized and aligned development process with high test coverage. However, there’s much improvement and refactoring needed on the code quality and entanglement itself.

Docker Compose
Mar 25, 2020

System and People Collaboration in Docker Compose

Until now, we analyzed Docker Compose from various traditional software engineering dependencies stand points (development view, runtime view, operations view). This does not give us a full perspective of the architectural structure of the project.

Docker Compose
Mar 31, 2020