Extensions are built and managed within a Contentful space through the Content Management APIs extension endpoint. To make it more convenient, the Create Contentful Extension CLI supports managing the extensions.

This article explains how to create and deploy a UI Extension from scratch using this tool.

Getting started

We recorded an eight minute video which gives an overview of the create-contentful-extension CLI.

Create a new UI Extension

To get started, generate your first extension using create-contentful-extension:

npx @contentful/create-contentful-extension my-first-extension

It will ask you what type of extension you want to create:

• Field extension
• Sidebar extension
• Entry extension
• Page extension

Then it creates a directory called my-first-extension inside the current folder.

my-first-extension
├── node_modules
├── .babelrc
├── .gitignore
├── .contentfulrc.json
├── package.json
├── extension.json
└── src
    ├── index.html
    ├── index.js
    └── index.css

Once the installation is done, you can open your project folder and install all development dependencies:

cd my-first-extension && npm install

Local development

To start development run the following commands in the newly created my-first-extension folder:

npm run login && npm run configure

It starts a new session with our CLI. As the CLI tool uses our Content Management API, you need to have a CMA access token to use all the commands.

Once you're successfully logged in, it asks what space and environment you want to use. Your answers (CMA token, space and environment ids) be will be saved to a local .contentfulrc.json.

When configuration part is finished you can actually start the development by typing the following command:

npm run start

It starts the development server and deploys the extension in development mode to the selected space. The extension will automatically reload if you make changes to the code.

Note: As Contentful runs in an HTTPS environment, temporarily disable the security checks in the browser. For example, "Load unsafe scripts" in Chrome.

Uploading a UI Extension to Contentful

When development is done, you need to install your extention to a space in production mode. To do so run the following command in your extension folder:

npm run deploy

It correctly bundles all extension dependencies in production mode and optimizes the build for the best performance, then it uploads build version of extension to a selected space.

Configuring a field to use an extension

Refer the section Assigning UI Extensions to a Field to assign the extension to the particular field where it needs to be used.

Managing UI Extensions via contentful-cli

Refer to our contentful-cli documentation

Version Locking

Contentful uses optimistic locking to avoid accidental non-idempotent operations such as update or delete.

While using the update and delete subcommands, it is mandatory to specify the version of the extension using the --version option. Alternatively, the --force option can be used that instructs the CLI to use the latest version of the extension.

Programmatic Usage

To manage an extension programmatically, refer the Content Management SDKs.