lint-condo

A Lint Container for Docker

Introduction

We built this container to provide an easy way to centralise and run linting on any project where you have Docker available. To paraphrase:

The best time to start linting your project was when you started it, but the second best time is today.

Linting can be contagious once you start, so with this all-in-one image you can conveniently add additional linters (markdown linting, yaml linting, etc). Our goal is to support popular linters while still keeping a reasonably small Docker image (~100MB according to Docker Hub).

How it Works

You will need to run the image while pointing it to your source code and providing a lint-condo.yaml or .lint-condo.yaml file to tell it which lint commands to run. You can see an example of this file in this repository here. As you'll probably observe, it's a list of shell commands.

You can then run it like this:

docker run -v `pwd`:/src/ singapore/lint-condo

Continuous Integration

Perhaps the best way to run linting is part of Continuous Integration. If you already use such a service, running lint-condo should be as simple as adding the lint-condo.yaml file and adding an extra test line to your CI script. It's recommended to put linting first as that is often the common cause of test failures once you add it. If you don't already use such a service, the easiest to set up for linting is CircleCI and you can use this example circle.yml:

machine:
  services:
    - docker

dependencies:
  override:
    - echo true

test:
  override:
    - docker run -v `pwd`:/src/ singapore/lint-condo

This project itself also tests with SemaphoreCI and Shippable and both work well once you configure them.

Versioning and Tags

For our own project linting, we use the latest version of the image (so we can be the canary in a coal mine) but we also endeavour to tag commits/releases so you can "pin" to these if you like. We use the great service Doppins to keep our package.json and requirements.txt up-to-date. Also note that the Docker Hub generates images from automated builds of the singapore/lint-condo repository for your peace of mind.

Included Linters

• scss_lint
• gometalinter
• proselint
• yamllint
• bootlint
• coffeelint
• csslint
• dependency-lint
• dockerfile_lint
• doiuse
• eslint + plugins
• jshint
• jslint
• markdownlint
• pug-lint
• remark-lint
• sass-lint
• stylelint
• tern-lint
• write-good
• xo

Example Output

lint-condo echoes the stdout of each linter, followed by a summary of test results. An example of this summary is below:

Summary:
✔ eslint
✔ jscs
✔ jshint
✔ yamllint
✔ markdownlint
✔ proselint
✔ remark
✔ write-good
✔ scss-lint
✔ sass-lint
✔ csslint
✔ stylelint
✔ doiuse
✔ sh test/colors.sh

You can note two important points from the above:

1. For brevity, the summary strips out the parameters from any "known" commands such as eslint, csslint, etc.
2. You can add any custom commands/scripts of your own too, such as the above sh test/colors.sh. In our own projects we additional internal "linting" scripts that enforce project guidelines.

Contributing/Collaborating

If we're missing any linters you'd like, please raise an issue. If you'd like to collaborate or contribute code, please do so as well.