---
title: Extension Project Structure
sidebar_position: 3
---

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# Extension Project Structure

The `apache-superset-extensions-cli` package provides a command-line interface (CLI) that streamlines the extension development workflow. It offers the following commands:

```
superset-extensions init: Generates the initial folder structure and scaffolds a new extension project.

superset-extensions build: Builds extension assets.

superset-extensions bundle: Packages the extension into a .supx file.

superset-extensions dev: Automatically rebuilds the extension as files change.
```

When creating a new extension with `superset-extensions init <extension-name>`, the CLI generates a standardized folder structure:

```
dataset_references/
├── extension.json
├── frontend/
│   ├── src/
│   ├── webpack.config.js
│   ├── tsconfig.json
│   └── package.json
├── backend/
│   ├── src/
│        └── dataset_references/
│   ├── tests/
│   ├── pyproject.toml
│   └── requirements.txt
├── dist/
│   ├── manifest.json
│   ├── frontend
│        └── dist/
│             ├── remoteEntry.d7a9225d042e4ccb6354.js
│             └── 900.038b20cdff6d49cfa8d9.js
│   └── backend
│        └── dataset_references/
│             ├── __init__.py
│             ├── api.py
│             └── entrypoint.py
├── dataset_references-1.0.0.supx
└── README.md
```

The `extension.json` file serves as the declared metadata for the extension, containing the extension's name, version, author, description, and a list of capabilities. This file is essential for the host application to understand how to load and manage the extension.

The `frontend` directory contains the source code for the frontend components of the extension, including React components, styles, and assets. The `webpack.config.js` file is used to configure Webpack for building the frontend code, while the `tsconfig.json` file defines the TypeScript configuration for the project. The `package.json` file specifies the dependencies and scripts for building and testing the frontend code.

The `backend` directory contains the source code for the backend components of the extension, including Python modules, tests, and configuration files. The `pyproject.toml` file is used to define the Python package and its dependencies, while the r`equirements.txt` file lists the required Python packages for the extension. The `src` folder contains the functional backend source files, `tests` directory contains unit tests for the backend code, ensuring that the extension behaves as expected and meets the defined requirements.

The `dist` directory is built when running the `build` or `dev` command, and contains the files that will be included in the bundle. The `manifest.json` file contains critical metadata about the extension, including the majority of the contents of the `extension.json` file, but also other build-time information, like the name of the built Webpack Module Federation remote entry file. The files in the `dist` directory will be zipped into the final `.supx` file. Although this file is technically a zip archive, the `.supx` extension makes it clear that it is a Superset extension package and follows a specific file layout. This packaged file can be distributed and installed in Superset instances.

The `README.md` file provides documentation and instructions for using the extension, including how to install, configure, and use its functionality.