GitHub Action for Chromatic

Builds and publishes your Storybook to Chromatic and runs visual regression tests.

This is a wrapper for chromatic-cli, which is also where the action's source code resides.

Getting started

In your git repository, create a file .github/workflows/chromatic.yml with the following contents:

# .github/workflows/chromatic.yml

# Workflow name
name: 'Chromatic'

# Event for the workflow
on: push

# List of jobs
jobs:
  chromatic-deployment:
    # Operating System
    runs-on: ubuntu-latest
    # Job steps
    steps:
      - uses: actions/checkout@v1
      - name: Install dependencies
        run: yarn
        # 👇 Adds Chromatic as a step in the workflow
      - name: Publish to Chromatic
        uses: chromaui/action@v1
        # Chromatic GitHub Action options
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          # 👇 Chromatic projectToken, refer to the manage page to obtain it.
          projectToken: ${{ secrets.CHROMATIC_PROJECT_TOKEN }}

Make sure to replace the value of projectToken with the project token provided to you by Chromatic. You can find it on the Manage page of your Chromatic project. The GitHub token is unrelated and will be set automatically. See below if you want to keep your projectToken secret.

Note: Chromatic requires full git history, so if you are using the action/checkout@v2 action, ensure you set the fetch-depth: 0 option.

Usage

- uses: chromaui/action@v1
  with:
    token: ${{ secrets.GITHUB_TOKEN }}
    projectToken: 'Your chromatic project token'
    buildScriptName: 'The npm script that builds your Storybook [build-storybook]'
    workingDir: 'Working directory for the package.json file'
    storybookBuildDir: 'Provide a directory with your built storybook; use if you've already built your storybook'
    allowConsoleErrors: 'Do not exit when runtime errors occur in storybook'
    autoAcceptChanges: 'Automatically accept all changes in chromatic: boolean or branchname'
    exitZeroOnChanges: 'Positive exit of action even when there are changes: boolean or branchname'
    exitOnceUploaded: 'Exit with 0 once the built version has been sent to chromatic: boolean or branchname'
    ignoreLastBuildOnBranch: 'Ignores latest build on target branch as a baseline if branch is no longer present in history (i.e. branch was rebased): branchname'

We suggest you use a secret to hide the project token:

- uses: chromaui/action@v1
  with:
    token: ${{ secrets.GITHUB_TOKEN }}
    projectToken: ${{ secrets.CHROMATIC_PROJECT_TOKEN }}

You can to configure secrets in the repository settings (/<owner>/<repository>/settings/secrets). However if you need to be able to run this action on pull requests from forks, because those can't access your secret.

Monorepo Support

The workingDir input can be used to direct Chromatic to a subdirectory where your Storybook exists. You will also need to provide this directory to other steps in your job, as needed. This can be done per-step, or with top-level defaults for run steps using defaults.run or jobs.<job_id>.defaults.run

jobs:
  chromatic-deployment:
    runs-on: ubuntu-latest
    defaults:
      run:
        working-directory: frontend
    steps:
      - uses: actions/checkout@v1
      - name: Install dependencies
        run: yarn
        # 👇 Runs yarn in ./frontend
        working-directory: frontend
      - name: Publish to Chromatic
        uses: chromaui/action@v1
        with:
          # 👇 Runs Chromatic CLI in ./frontend
          workingDir: frontend
          token: ${{ secrets.GITHUB_TOKEN }}
          projectToken: ${{ secrets.CHROMATIC_PROJECT_TOKEN }}

Outputs

Name	Type	Description
url	string	An alias for the build URL (e.g. https://www.chromatic.com/build?appId=<app id goes here>&number=<build number>)
buildUrl	string	The build URL (e.g. https://www.chromatic.com/build?appId=<app id goes here>&number=<build number>)
storybookUrl	string	The Storybook preview URL for your current branch / Pull Request (e.g. https://<app id goes here>-<branch hash>.chromatic.com/)
code	string	The exit code for the current run of the Chromatic CLI

Checkout depth

Version 2 of the actions/checkout action will only checkout a single commit without history by default. Chromatic needs the full git history in order to track changes over time. Set fetch-depth: 0 to enable this. See actions/checkout for details.

Issues and support

Please report any issues in the chromatic-cli repository. We provide documentation and support chat at https://www.chromatic.com/docs/.