Generating server code

With server code generation, you can generate server-side boilerplate code from your OpenAPI 3 specification. This enables an API-first development approach, where you can download a running server based on your API specification and use it as a starting point for development of your business logic.

Supported languages and frameworks include:

  • Go - Chi server
  • NodeJS - express
  • Java - JAX-RS
  • Python - Flask

Generating server code

To generate server side boilerplate from your OpenAPI 3 spec:

  1. Navigate to the API tab.
  2. Select an API containing an OpenAPI 3 specification.
  3. In the right sidebar, select the code generation icon </>. Edit API
  4. In the Code Generation panel, choose the language and framework for which you want to generate boilerplate and select the Generate Code button.

The generated code will automatically be downloaded as a zip archive. You may need to open the Downloads option of your browser to find the archive. The name of the file includes the name of the API the code is generated from as well as the language and framework selected.

Using the generated code

The generated code structure will depend on which language you choose. All of the supported languages will cover some of the major features from your OpenAPI 3.0 specification. Here are some features that you can expect from the generated code:

  • All operations will be generated as routes in your server boilerplate with a stubbed section of code for each endpoint where you can add your business logic. This stub may include a default response, usually taken from the API definition Response section of the associated endpoint.
  • You can access request bodies, parameters, path parameters, and headers in each of these routes when applicable and use them in your business logic.
  • You can start a server from this generated code. There will be a README.md file describing prerequisites and instructions to start the server.
  • See the framework's relevant documentation for more details on configuring or customizing the generated code.

Generating only routes and interfaces

Apart from code generated for configuring the routes and stubs for the implementation of each endpoint, the generated code will also include other files like the README.md, a list of dependencies, server setup code, and other items required by the specific framework selected. These generated files will most likely be edited and customized by you after code generation.

You can select the Only generate routes and interfaces option when you download generated code. This will only generate code relevant to the paths and components in the OpenAPI schema and leave out all other files. This will enable you to update only files relevant to new or changed endpoints, and avoid overwriting your customized files with generated boilerplate code.