Designing APIs with Swagger and OpenAPI: Version 4 (MEAP Edition)

Good API design is about more than listing endpoints: it is about giving the people and services that depend on them a clear, dependable contract. This Version 4 MEAP edition of Designing APIs with Swagger and OpenAPI shows how API descriptions can support that work—from documenting an existing interface to shaping a new one and managing its evolution.

Joshua S. Ponelat and Lukas Rosenstock build the discussion around practical API scenarios, explaining OpenAPI fundamentals alongside tools and workflows for using those definitions. The result is a hands-on look at how API design connects documentation, implementation, and change management.

Start with the language of APIs

The opening chapters establish what APIs do within a larger software ecosystem, then introduce OpenAPI definitions and the Swagger Editor. Readers work through requests, responses, resources, authentication, authorization, and hosting API documentation. The focus is not only on writing a definition, but on understanding how people and tools can use it.

Follow a design from idea to implementation

The book then takes a design-first approach through a web-application project. Its outline follows API planning into a change workflow, frontend development, backend work with and Swagger Codegen, and release. This connected view helps make the relationship between an API contract and the surrounding development process easier to see.

Make room for change

APIs rarely stand still. Later chapters consider iteration and versioning, breaking changes, filters and pagination, error handling with problem+json, and advanced JSON Schema. These subjects matter when teams need to evolve an interface while keeping its behavior understandable to the people and systems that rely on it.

Explore the wider OpenAPI toolkit

The final section broadens the scope to composing API definitions, comparing Swagger 2.0 with OpenAPI 3.0 and 3.1, building OpenAPI tools, securing public APIs with OAuth, deploying an API gateway, and using specifications for testing and monitoring.

For developers and API designers

This edition will interest readers who want a practical introduction to describing RESTful APIs and using those descriptions throughout development. Its progression—from fundamentals to a project workflow and more advanced topics—offers a useful way to understand OpenAPI as both a specification and a working part of API design.