👷🏻‍♂️ Generate a mock service / emulator from OpenAPI specs!

This tool creates a simple Express/NodeJS server from a given OpenAPI spec file or url. Once created you can run a client against the emulated API and make live changes to the emulated service.

It's useful to mock out dependencies for speeding up development, especially in a microservice environment where there are a lot of service dependencies.

• VS Code
• OpenApi VS Code extension that can preview OpenAPI with the Swagger Editor
• Node 18
• TypeScript installed globally

Build the tool and install (public npm package will be coming):

npm i
npm run build
npm i -g

Run it:

api-moka -o "mocks" -s "test/communicationservicesrooms.json" "https://raw.githubusercontent.com/Azure/azure-rest-api-specs/main/specification/communication/data-plane/Identity/stable/2023-08-01/CommunicationIdentity.json" --run

This command

• generates a simple Express server for your APIs
• opens the new project in VS Code
• builds the server and starts it
• hot-reload is supported!
• to only generate the code, don't pass the --run argument

The structure of the generated server is as follows:

src/
  {service}/
    api.ts
    openapi.json
  app.ts

While the generated emulator is running:

• Open an openapi.json from one of the services and launch the preview to see it in Swagger Editor
• Open the corresponding api.ts side-by-side
• In Swagger Editor, choose a route and click "Try It"
• Fill in all required request properties and headers
• Click "Execute"
• You can see the returned response from the emulator!
• To change the returned response, edit the route in api.ts and save the file
• Wait until hot-reload did its thing and execute the request again, you will see your changes in the response.