jest-docker-mysql

Jest preset to run MySQL in docker

Features

• Run a MySQL docker container before test and remove it after test finished
• Run SQL scripts before each test suite (test file) and run clean-up SQL scripts after each test suite
• Run SQL scripts before and after each test case according to the file name specified in test case name string

Caveat: Do note that the test cases must not run concurrently as they use the same MySQL database. Thus the --runInBand option must be added to the jest command

jest --runInBand

Install

yarn add @mangroves/jest-docker-mysql --dev

You can use npm or other tools as an alternative.

Usage

There are 3 alternatives to use this package.

Use as a preset

In your jest.config.js (Or jest field in package.json):

module.exports = {
  preset: '@mangroves/jest-docker-mysql',
}

Specify scripts

If you've already set another package as the preset, you can set setupFilesAfterEnv, globalSetup and globalTeardown manually.

// jest.config.js
module.exports = {
  setupFilesAfterEnv: [
    '@mangroves/jest-docker-mysql/lib/setup-after-env.js',
    // ...other files
  ],
  globalSetup: '@mangroves/jest-docker-mysql/lib/global-setup.js',
  globalTeardown: '@mangroves/jest-docker-mysql/lib/global-teardown.js',
}

Import Setup and Teardown Scripts

Maybe even globalSetup and globalTeardown are taken by your own script, but don't worry, you can still use this package.

// jest.config.js
module.exports = {
  setupFilesAfterEnv: [
    '@mangroves/jest-docker-mysql/lib/setup-after-env.js',
    // ...other files
  ],
  globalSetup: 'path/to/your/script-setup.js',
  globalTeardown: 'path/to/your/script-teardown.js',
}

In your setup script:

// path/to/your/script-setup.js
import { globalSetup } from '@mangroves/jest-docker-mysql/lib/global-setup.js'

const yourSetup = async () => {
  await globalSetup()
}

export default yourSetup

The same for the teardown script.

Connect to MySQL Container

After you execute the jest command and the test cases are running, you can connect to the MySQL container and use it.

Example:

// xxx.spec.js
import { config } from '@mangroves/jest-docker-mysql/lib/config'

describe('Your test case', () => {
  let connection
  beforeAll(async () => {
    // Use your mysql library to connect the database
    connection = await createConnection({
      host: config.db.host,
      port: config.db.port,
      user: config.db.user,
      pass: config.db.pass,
    })
  })

  afterAll(async () => {
    // Don't forget to close connection after test run
    connection.close()
  })
})

Environment Variables

Sometimes you don't want to stop and remove the MySQL container, or you don't want to start a container every time you run the test.

You can set an environment variable whose key is JEST_DOCKER_MYSQL_ENV to local.

And you may need this lib: cross-env

It's practical especially in jest watch mode:

cross-env JEST_DOCKER_MYSQL_ENV=local jest --watch --runInBand

Don't forget to remove the container manually if you don't need it any more.

Config File

Create a file named jest-docker-mysql-config.js and put it under the root directory as the config file.

Use defineConfig exported by this package to get better type intellisense.

// jest-docker-mysql-config.js
const { defineConfig } = require('@mangroves/jest-docker-mysql')

module.exports = defineConfig({
  db: {
    port: 6666,
  },
})