Swagger API documentation in NestJS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Swagger in the context of API development?

Swagger is a tool that helps you describe, design, and document your APIs in a way that is easy to understand and use. It creates interactive API documentation that lets users try out API calls directly from the browser.

beginner

How do you enable Swagger in a NestJS application?

You enable Swagger by installing the @nestjs/swagger package and then setting up the SwaggerModule in your main.ts file. You create a document describing your API and serve it with a route like '/api'.

intermediate

What decorator is used in NestJS to add metadata for Swagger documentation on a controller method?

The @ApiOperation decorator is used to add a summary or description for a controller method in Swagger documentation.

intermediate

Why is it important to use DTOs (Data Transfer Objects) with Swagger in NestJS?

DTOs define the shape of data sent or received by the API. Using DTOs with Swagger helps generate clear and accurate API models so users know what data to send or expect.

advanced

How can you secure your Swagger API documentation in NestJS so only authorized users can access it?

You can protect the Swagger route by applying authentication guards or middleware to the route serving the Swagger UI, ensuring only authorized users can view the API docs.

Which NestJS package do you install to add Swagger support?

A nestjs-swagger-ui

B @nestjs/api-docs

C swagger-ui-express

D @nestjs/swagger

The official package for Swagger support in NestJS is @nestjs/swagger.

What method from SwaggerModule is used to create the API documentation object?

A buildApi()

B generateDoc()

C createDocument()

D initSwagger()

SwaggerModule.createDocument() generates the API documentation object from your app and options.

Which decorator adds a summary description to a controller method in Swagger docs?

A @ApiSummary()

B @ApiOperation()

C @ApiDescription()

D @ApiDoc()

@ApiOperation() adds a summary or description to a controller method for Swagger.

What is the main benefit of using Swagger UI for your API?

A It provides interactive, easy-to-use API documentation

B It encrypts API requests

C It automatically fixes bugs in your API

D It replaces the need for writing code

Swagger UI provides interactive documentation so users can explore and test your API easily.

How do you serve the Swagger UI at a specific route in NestJS?

A Use SwaggerModule.setup() with the route path

B Add a controller method returning HTML

C Configure it in main.ts with app.use()

D Set a global middleware

SwaggerModule.setup() lets you specify the route where Swagger UI is served.

Explain how to set up Swagger API documentation in a NestJS project from scratch.

Think about the steps in main.ts and how decorators add info.

Describe why using DTOs is helpful when generating Swagger documentation in NestJS.

Consider how data structure helps explain the API.