setup-mysql-action

Starts a MySQL server in a Docker container for your test run and removes it when the job ends. The same container image runs on Linux and Windows runners; on Windows it runs inside WSL2, so no native MySQL installation is needed on either platform.

Prerequisites

This action does not provision WSL or Docker itself. On Windows runners it requires setup-wsl-action to run first in the same job. That action provisions WSL2 and Docker, keeps the instance alive, and exports the WSL_DISTRIBUTION, WSL_IP, and WSL_TOOLS_MODULE_PATH environment variables this action relies on. On Linux runners setup-wsl-action is a no-op but should still be included so the workflow is uniform.

If setup-wsl-action has not run, the action fails fast with a clear error.

Usage

See action.yml

steps:
- name: Setup WSL
  uses: Particular/setup-wsl-action@v1
- name: Setup MySQL
  uses: Particular/setup-mysql-action@v1.0.0
  with:
    connection-string-name: MySQLConnectionString
- name: Run tests
  shell: pwsh
  run: |
    $connectionString = $Env:MySQLConnectionString
    # Use the connection string in tests...

connection-string-name is required. database-name and username default to nservicebus and particular, the values the NServiceBus test setup used, so switching an existing workflow is a drop-in change.

Inputs

Input	Required	Default	Description
connection-string-name	Yes	-	Name of the environment variable that receives the MySQL connection string.
database-name	No	nservicebus	Database created for the connection string.
username	No	particular	User created for the connection string.
image-tag	No	8.4	Tag of the MySQL image.
init-script	No	-	Path to an SQL script, or a comma-separated list of scripts, executed once the server is ready.
registry-login-server	No	index.docker.io	Container registry to log in to on Windows runners.
registry-username	No	-	Username for the registry login. Login happens only when both username and password are set.
registry-password	No	-	Password for the registry login. Login happens only when both username and password are set.

Connection string

The action creates a root account and a user for the connection string, both with generated passwords, and exports the connection string to the environment variable you name:

Data Source=127.0.0.1;Initial Catalog=nservicebus;User ID=particular;Password=<password>;AllowUserVariables=True;AutoEnlist=false;ConnectionReset=true;Connect Timeout=60

• On Linux the host is 127.0.0.1.
• On Windows the host is the WSL2 VM IP address exported by setup-wsl-action.

The keyword set is what the NServiceBus MySql transport expects, so the string can be passed straight to MySqlConnection.

Init scripts

init-script takes one SQL file, or several separated by commas. A list runs in order:

- name: Setup MySQL
  uses: Particular/setup-mysql-action@v1.0.0
  with:
    connection-string-name: MySQLConnectionString
    init-script: .github/workflows/scripts/01-create-schema.sql,.github/workflows/scripts/02-seed.sql

The scripts run as root once the server accepts connections, so they can create databases, users, and grants beyond the defaults. They execute with the mysql client inside the container, so nothing needs to be installed on the runner. The action normalizes line endings before piping a script in, so a Windows checkout does not corrupt the SQL.

mysql CLI shim

The action puts a mysql shim on PATH that forwards to the client inside the container, so the same command works on both platforms:

mysql --user=<user> --password=<password> --database=<database> --execute="SELECT 1"

The shim has no credentials of its own. Pass the user and password of any account the server knows, and SQL can also be piped through stdin.

Cleanup

The action runs dist/index.mjs for both main and post. The post step removes the container it started. On hosted runners this is harmless, since the runner VM is destroyed at the end of the job, but it keeps long-lived self-hosted runners from accumulating orphaned containers.

Local development

Install dependencies and build the bundle:

npm install
npm run prepare

The prepare script runs @vercel/ncc to bundle index.mjs and its dependencies into dist/index.mjs. The committed dist/ is what the runner executes; the source index.mjs is not used directly.

To test setup.ps1 directly:

$Env:RUNNER_OS=Linux
.\setup.ps1 -ContainerName setup-mysql-local -ConnectionStringName MySQLConnectionString

Open the folder in Visual Studio Code with the DevContainer for a consistent development environment with Node.js, Docker-in-Docker, and PowerShell.

License

The scripts and documentation in this project are released under the MIT License.