Differences Between Spring REST Docs and Swagger

APIs have become the building blocks of software development. But, an API without proper documentation is like a treasure map without directions. So, let’s explore the fascinating world of API documentation with a focus on two prominent players in this field: Spring REST Docs and Swagger. This comparative study will help you understand their features, strengths, and how they can revolutionize your API documentation process. So, without further ado, let’s get started!

Introduction to API Documentation

Before we jump into the comparison, let’s briefly talk about what API documentation is. API (Application Programming Interfaces) documentation is a set of human-readable instructions for using and integrating with an API. It plays a crucial role in ensuring the success of any API, whether it’s private or public.

API documentation typically includes detailed information about an API’s available endpoints, methods, resources, authentication protocols, parameters, and headers, as well as examples of common requests and responses. It serves as a comprehensive manual, providing clear instructions on interacting with the API effectively and leveraging its functionalities for desired outcomes.

API documentation can be of different types, some of the most common ones are:

• Reference documentation: Provides a rundown of every endpoint, including its methods, parameters, and accepted data types.
• Tutorial documentation: Guides users through the process of performing specific tasks with the API.
• How-to guides: Offers step-by-step instructions on how to solve common problems or fulfill common requirements using the API.
• Conceptual documentation: Explains the underlying concepts and principles of the API.

Effective API documentation improves the developer experience, facilitates cross-team collaboration, reduces code duplication, and streamlines the onboarding process for new employees. It also helps potential consumers understand and experiment with an API, leading to increased adoption and, by extension, revenue.

Teams that prioritize API documentation typically see higher rates of API adoption, fewer support tickets, and—in the case of public APIs—increased revenue. Therefore, it’s essential to write clear, concise, and comprehensive API documentation. You can use tools like Apidog to create and manage your API documentation.

Spring REST Docs: An Overview

Spring REST Docs is a framework developed by the Spring community that helps you document RESTful services. It takes a unique approach by combining hand-written documentation written with Asciidoctor and auto-generated snippets produced with Spring MVC Test. This approach frees you from the limitations of the documentation produced by tools like Swagger.

Here are some key features of Spring REST Docs:

• Accuracy: The documentation is generated from tests, ensuring that it accurately matches the actual behavior of the API.
• Readability: It combines hand-written documentation with auto-generated document snippets, making the documentation both accurate and readable.
• Flexibility: It supports both JSON and XML, and the tests that produce the snippets can be written using either Spring MVC Test support, Spring Webflux’s WebTestClient, or REST-Assured.
• Integration: The output is ready to be processed by Asciidoctor, a publishing toolchain centered around the AsciiDoc syntax. This is the same tool that is used to generate the Spring Framework’s documentation.

Spring REST Docs aims to produce documentation that is accurate, concise, and well-structured, allowing the web service consumers to get the information they need with a minimum of fuss. It’s an excellent tool for teams looking to provide high-quality, up-to-date documentation for their RESTful services.

To get started with Spring REST Docs, you would typically add it as a dependency in your project. For example, if you’re using Maven as your build tool, you would add the spring-restdocs-mockmvc dependency to your POM file. Then, you can use the Spring MVC Test framework to make requests to the REST services which are to be documented. Running the test produces documentation snippets for the request and the resulting response.

Overall, Spring REST Docs is a powerful tool for creating robust, accurate, and easy-to-read API documentation. It’s particularly useful for teams that value accuracy and readability in their API documentation.

Introduction to Swagger

On the other hand, Swagger, now known as OpenAPI, Swagger is an open-source API design and documentation tool that helps developers design, build, document, and test RESTful APIs. It’s a set of rules, or a specification, for a format describing REST APIs. The format is both machine-readable and human-readable, which makes it useful for sharing documentation among product managers, testers, and developers.

Here are some key features of Swagger:

• Interactive API documentation: Swagger can automatically generate interactive API documentation that lets your users try out the API calls directly in the browser.
• Client SDKs and server stub code: Swagger can automatically generate client SDKs and server stub code, making it easier for developers to develop, test, and deploy APIs.
• Design and build APIs: Swagger helps developers design and build APIs faster and more easily.
• Test RESTful APIs: Swagger aids in testing RESTful APIs.

Swagger does this by asking your API to return a YAML or JSON that contains a detailed description of your entire API. This file is essentially a resource listing of your API which adheres to OpenAPI Specification. The specification asks you to include information like:

• What are all the operations that your API supports?
• What are your API’s parameters and what does it return?
• Does your API need some authorization?
• And even fun things like terms, contact information, and license to use the API.

Overall, Swagger is a powerful tool for creating robust, accurate, and easy-to-read API documentation. It’s particularly useful for teams that value accuracy and readability in their API documentation.

Tutorial: How to Write API Documentation using Swagger / Postman / Apidog

Find out with a step-by-step guide on how to write API documentation using the hottest API applications like Apidog, Postman, and Swagger!

Apidog BlogSteven Ang Cheong Seng

Comparing Spring REST Docs and Swagger

Now, let’s compare these two based on several factors.

Accuracy

• Spring REST Docs: It uses a test-driven approach to generate API documentation. This ensures that the documentation always matches the actual behavior of the API. Therefore, it is highly accurate.
• Swagger: Swagger’s method of inspecting your code can lag behind your code. It’s possible to make a change in your code that Swagger fails to understand and won’t process properly until Swagger gets updated. Therefore, it might not always be as accurate as Spring REST Docs.

When it comes to accuracy, Spring REST Docs has an edge. Since it generates documentation from your tests, it ensures that the documentation is always in sync with your code. Swagger, however, relies on manual updates, which can lead to discrepancies.

User Interface

• Spring REST Docs: The output of Spring REST Docs is suitable for publishing. It does not provide an interactive UI like Swagger.
• Swagger: Swagger automatically generates interactive API documentation. This lets your users try out the API calls directly in the browser. Therefore, it provides a more interactive and visually appealing user interface.

Swagger shines in terms of user interface. It provides an interactive UI for your API documentation, making it easier for users to understand and test your API. Spring REST Docs, while structured and concise, lacks this interactivity.

Ease of Use

• Spring REST Docs: It requires writing tests for your documentation. While this ensures accuracy, it might be more time-consuming and require more effort compared to Swagger.
• Swagger: Swagger requires a lot of annotation, which can be painful to include the descriptive text you want in an API document. However, it automatically generates client SDKs and server stub code, making it easier for developers to develop, test, and deploy APIs.

Both tools have their strengths and weaknesses in terms of ease of use. Swagger’s interactive UI and design-first approach make it easy to use for beginners. However, Spring REST Docs’ test-driven approach might appeal more to developers who prefer writing tests.

Who Should Write the API Documentation

Writing interface documentation is a crucial step in the API development process, and it has a significant impact on subsequent tasks such as development, testing, and documentation writing.

Apidog LearningDavid Demir

Apidog: A better alternative to Spring REST Docs and Swagger

Apidog is an all-in-one API collaboration platform that provides a comprehensive solution for API development. It combines the functionalities of several tools into one, tackling the data synchronization problem among different systems using a set of systems and a set of data.

• API Documentation: Apidog allows you to quickly create APIs, define API-related information, and API request and response parameters.
• API Debugging: Apidog provides developers with convenient API request functions. You can directly initiate requests on the visual page to obtain API response results.
• API Mocking: Mocking is one of the core functions of Apidog. It helps developers in rapidly generating API responses during design or debugging phases.
• API Automated Testing: As long as the API documentation is well defined, API debugging, API data mocking, and API automated testing can be directly used without redefining.
• Import External APIs: Apidog supports importing API documents in formats such as Postman and Swagger.
• Generate Online Documentation: Apidog supports generating online documentation for API documents. Online API documentation has a format that is easy to read and understand, as well as a searchable and interactive website.

Apidog is designed to solve common problems in API management. It provides an efficient, timely, and accurate solution. The tool for API documentation and development debugging is the same, ensuring complete consistency between the API documentation and API development after debugging. This approach provides an efficient, timely, and accurate solution.

Spring REST Docs and Swagger, Apidog might be a better alternative if you’re looking for an all-in-one solution that provides API documentation, API debugging, API mocking, and API automated testing. It’s particularly useful for teams that value efficiency and consistency in their API documentation.

Conclusion

Both Spring REST Docs and Swagger have their strengths and can be useful depending on your needs. If you prioritize accuracy and don’t mind writing tests, Spring REST Docs might be the tool for you. But if you prefer a more interactive and user-friendly interface, Swagger could be a better choice.