Quickstart Guide to Building a Docker Extension

--- title: Quickstart description: Guide on how to build an extension quickly keywords: quickstart, extensions aliases: - desktop/extensions-sdk/tutorials/initialize/ - /desktop/extensions-sdk/quickstart/ weight: 20 --- Follow this guide to get started with creating a basic Docker extension. The Quickstart guide automatically generates boilerplate files for you. ## Prerequisites - [Docker Desktop](/manuals/desktop/release-notes.md) - [NodeJS](https://nodejs.org/) - [Go](https://go.dev/dl/) > [!NOTE] > > NodeJS and Go are only required when you follow the quickstart guide to create an extension. It uses the `docker extension init` command to automatically generate boilerplate files. This command uses a template based on a ReactJS and Go application. In Docker Desktop settings, ensure you can install the extension you're developing. You may need to navigate to the **Extensions** tab in Docker Desktop settings and deselect **Allow only extensions distributed through the Docker Marketplace**. ## Step one: Set up your directory To set up your directory, use the `init` subcommand and provide a name for your extension. ```console $ docker extension init <my-extension> ``` The command asks a series of questions about your extension, such as its name, a description, and the name of your Hub repository. This helps the CLI generate a set of boilerplate files for you to get started. It stores the boilerplate files in the `my-extension` directory. The automatically generated extension contains: - A Go backend service in the `backend` folder that listens on a socket. It has one endpoint `/hello` that returns a JSON payload. - A React frontend in the `frontend` folder that can call the backend and output the backend’s response. For more information and guidelines on building the UI, see the [Design and UI styling section](design/design-guidelines.md). ## Step two: Build the extension To build the extension, move into the newly created directory and run: ```console $ docker build -t <name-of-your-extension> .

This guide provides a quick start to creating a basic Docker extension using the `docker extension init` command. It covers the prerequisites (Docker Desktop, NodeJS, Go), setting up the directory with the `init` subcommand, and building the extension using `docker build`. The generated extension includes a Go backend and a React frontend.