Unlock the Power of Automated API Documentation and SDK Generation with Fern
As developers, we often dread writing documentation, but what if we had a tool that could automatically generate it for us, along with an SDK, TypeScript types, and more? Enter Fern, a revolutionary tool that allows you to define an API and generate all the necessary artifacts with ease.
In this guide, we’ll explore how to integrate Fern into your workflow to define and document your APIs. We’ll use Node.js and Express to build a basic CRUD API for an animal farm, and then use Fern to generate the necessary documentation, SDK, and TypeScript types.
Setting Up a Demo Project with Node.js and Express
To get started, we’ll create a new Node.js project with Express. We’ll use the express-generator package to create a basic CRUD API for an animal farm. This will allow us to add, list, retrieve, and delete animals from the list.
Defining Our API Routes with Fern
Once we have our Express API set up, we can start defining our API routes with Fern. Fern uses a simple YAML file to define the API endpoints, request and response types, and authentication settings. We’ll create a animals.yaml file in the fern/api/definition directory to define our API endpoints.
Exploring Fern’s Configuration Files
Fern has two main configuration files: fern.config.json and generators.yaml. The fern.config.json file sets the project namespace and version number, while the generators.yaml file configures the output of the fern generate command.
A Brief Overview of Fern’s Type System
Fern has a powerful type system that allows you to define custom types that match your data model. This ensures that your API documentation and generated SDKs are accurate and up-to-date.
Converting an OpenAPI Spec into Fern
One of the best features of Fern is its interoperability with OpenAPI. You can convert an OpenAPI spec into a Fern definition, and vice versa. This allows you to leverage the strengths of both tools and create a seamless development experience.
Generating Artifacts with Fern
Once we’ve defined our API endpoints and configured our generators, we can run the fern generate command to generate our desired output. This can include SDKs, TypeScript types, OpenAPI documentation, and more.
Modifying Our App to Incorporate Fern Types
Finally, we’ll modify our Express app to use the generated Fern types. This ensures that our API documentation and generated SDKs are always up-to-date and accurate.
Conclusion
Fern is a game-changer for API development. With its automated documentation and SDK generation, you can focus on building your API without worrying about the tedious tasks of documentation and SDK creation. Try Fern today and see how it can revolutionize your API development workflow!