dev/react-plugin-tools/react_plugin_template/README.md

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**Table of Contents**  *generated with [DocToc](https://github.com/thlorenz/doctoc)*

- [{{PROJECT_NAME}}](#project_name)
  - [Development](#development)
  - [Best Practices](#best-practices)
  - [Troubleshooting](#troubleshooting)

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# {{PROJECT_NAME}}

This is a React plugin template for Apache Airflow that builds as a library component.

## Development

This template is configured to build your React component as a library that can be consumed by other applications.

### Available Scripts

- `pnpm dev` - Start development server with hot reload
- `pnpm build` - Build the library for production
- `pnpm build:types` - Generate TypeScript declaration files only
- `pnpm build:lib` - Build the JavaScript library only
- `pnpm test` - Run tests
- `pnpm lint` - Check code quality
- `pnpm format` - Format code

### Library Output

When you run `pnpm build`, the template generates:

- `dist/main.js` - ES module JavaScript library
- `dist/main.d.ts` - TypeScript declaration file
- Source maps for debugging

### Usage as a Library

After building, other applications can import your component:

```typescript
import { PluginComponent } from 'your-plugin-name';

// Use in your React app
<PluginComponent />
```

### Development Mode

For development and testing, use `pnpm dev` which will:

- Start a development server on port 5173
- Load the component using `src/dev.tsx` entry point
- Enable hot module replacement

### Library Configuration

The template is configured with:

- **Vite** for fast building and development
- **TypeScript** with declaration file generation
- **CSS injection** - styles are automatically injected into the JavaScript bundle
- **External dependencies** - React and other common libraries are marked as external to reduce bundle size

### Upgrading dependencies

Be mindful when upgrading dependencies that are marked as external in `vite.config.ts`, those are shared dependencies with the host application
(Airflow UI) and should remain in a compatible version range to avoid issues.

### Customization

1. **Component Props**: Update the `PluginComponentProps` interface in `src/main.tsx`
2. **External Dependencies**: Modify the `external` array in `vite.config.ts`
3. **Build Output**: Adjust library configuration in `vite.config.ts`

### Package Configuration

The `package.json` is configured with:

- `main` and `module` pointing to the built library
- `types` pointing to generated declaration files
- `exports` for modern import/export support
- `files` array specifying what gets published

This ensures your plugin can be consumed as both a CommonJS and ES module with full TypeScript support.

## Best Practices

1. **Keep React External**: Always mark React ecosystem as external to avoid conflicts
2. **Global Naming**: Use standardized global name (`AirflowPlugin`) for consistency
3. **Error Handling**: Implement proper error boundaries and fallbacks
4. **TypeScript**: Use proper typing for plugin props and exports
5. **Bundle Size**: Monitor bundle size and externalize large dependencies if needed

## Troubleshooting

### Common Issues

**"Failed to resolve module specifier 'react'"**

- Ensure React is marked as external in `vite.config.ts`
- Verify host application exposes React globally

**"Cannot read properties of null (reading 'useState')"**

- React instance mismatch - check external configuration
- Verify global React is properly set in host application

**"Objects are not valid as a React child"**

- Ensure you're returning component functions, not JSX elements
- Check that lazy loading returns proper component structure

**MIME type issues**

- Ensure `.js` and `.cjs` files are served with correct MIME type

For more help, check the main project documentation.

### Deployment to Airflow Plugins

Once the development is complete, you can build the library using `pnpm build` and then host the content of the `dist` folder. You can do that on your own infrastructure or within airflow
by adding static file serving to your api server via registering a plugin `fastapi_apps`. You can take a look at the [Airflow documentation](https://airflow.apache.org/docs/apache-airflow/stable/plugins.html) for more information on how to do that.