There are many different choices when it comes to finding the right framework for building an API. One of those choices is Swagger. But what does Swagger do above and beyond other frameworks? Why should you consider it for developing APIs?
What is Swagger?
First, let's start with what an API is. An Application Program Interface, or API, specifies how software components should interact with one another. It's effectively a linking mechanism between one program and another, making them compatible and capable of interacting with one another. But APIs can be written in several different kinds of languages, which sometimes can be difficult for a machine (or a user) to understand.
As not all programs are written in the same language, it can be difficult for one platform to understand the other's function, or a person to understand the coding behind a design. Imagine being at a restaurant in an unfamiliar country and trying to read the menu. Without a translator to help you, it's futile. You likely wouldn't have the slightest clue where to begin.
That's where Swagger comes in. It's kind of like a Babel Fish for API documentation, able to be both human and machine readable.
What Does Swagger Do?
According to this readme.io blog post, "Swagger is a framework for describing your API using a common language that everyone can understand. Think of it as a blueprint for a house. You can use whatever building materials you like, but you can't step outside the parameters of the blueprint."
Swagger was designed to be a language-agnostic interface to develop and better understand REST APIs. Not just for creating easy-to-understand and concise documentation, it can also be used to test and debug any API issues you may run into. The fact that it is both machine and human readable makes it simple to document and share any findings.
Unlike RAML, Swagger is an architecture that is typically only used for describing your API, rather than being designed for API-first development. You can describe your APIs with Swagger in one of two ways:
- A top-down approach: Create your Swagger definition with the Swagger Editor before using Codegen tools to finalize the skeleton of your API.
- A bottom-up approach: Use your existing REST API and create a Swagger definition. Depending on which framework your API was developed in (such as node.js or JAX-RS), it may also be able to be generated automatically.
Interested in learning more? Check out or blog post, Swagger vs. RAML - Which is Better for Building APIs?