Swagger 2.0 and OpenAPI 3.0 parser/validator

Features

• Parses Swagger specs in JSON or YAML format
• Validates against the Swagger 2.0 schema or OpenAPI 3.0 Schema
• Resolves all $ref pointers, including external files and URLs
• Can bundle all your Swagger files into a single file that only has internal $ref pointers
• Can dereference all $ref pointers, giving you a normal JavaScript object that's easy to work with
• Tested in Node.js and all modern web browsers on Mac, Windows, and Linux
• Tested on over 1,500 real-world APIs from Google, Microsoft, Facebook, Spotify, etc.
• Supports circular references, nested references, back-references, and cross-references
• Maintains object reference equality — $ref pointers to the same value always resolve to the same object instance

Related Projects

• Swagger CLI
• Swagger Express Middleware

Example

SwaggerParser.validate(myAPI, (err, api) => {
  if (err) {
    console.error(err);
  } else {
    console.log("API name: %s, Version: %s", api.info.title, api.info.version);
  }
});

Or use async/await or Promise syntax instead. The following example is the same as above:

try {
  let api = await SwaggerParser.validate(myAPI);
  console.log("API name: %s, Version: %s", api.info.title, api.info.version);
} catch (err) {
  console.error(err);
}

For more detailed examples, please see the API Documentation

Installation

Install using npm:

npm install @apidevtools/swagger-parser

Node.js 22.19 or later is required.

Usage

When using Swagger Parser in Node.js apps, you'll probably want to use CommonJS syntax:

const SwaggerParser = require("@apidevtools/swagger-parser");

When using a transpiler such as Babel or TypeScript, or a bundler such as Webpack or Rollup, you can use ECMAScript modules syntax instead:

import * as SwaggerParser from "@apidevtools/swagger-parser";

Browser support

Swagger Parser supports recent versions of every major web browser. Older browsers may require Babel and/or polyfills.

To use Swagger Parser in a browser, you'll need to use a bundling tool such as Webpack, Rollup, Parcel, or Browserify. Some bundlers may require a bit of configuration, such as setting browser: true in rollup-plugin-resolve.

API Documentation

Full API documentation is available right here

Security

The library, by default, attempts to resolve any files referenced using $ref, without considering file extensions or the location of the files. This can result in Local File Inclusion (LFI), thus, potentially sensitive information disclosure. Developers must be cautious when working with documents from untrusted sources. See here for more details and information on how to mitigate LFI.

Contributing

I welcome any contributions, enhancements, and bug-fixes. Open an issue on GitHub and submit a pull request.

Use the current Node.js LTS release for development. TypeScript tests use the TypeScript 7 compiler, while ESLint uses the TypeScript 6 compatibility API via Microsoft's recommended package aliases.

To test the project locally on your computer:

1. Clone this repo
   git clone https://github.com/APIDevTools/swagger-parser.git

2. Install dependencies
   pnpm install

3. Run the tests
   pnpm test

4. Check the code coverage
   pnpm run coverage

License

Swagger Parser is 100% free and open-source, under the MIT license. Use it however you want.

This package is Treeware. If you use it in production, then we ask that you buy the world a tree to thank us for our work.

Big Thanks To

Thanks to these awesome companies for their support of Open Source developers ❤