Setting up a dev environment

SwaggerUI includes a development server that provides hot module reloading and unminified stack traces, for easier development.

Prerequisites

• git, any version
• Node.js >=24.14.0 and npm >=11.9.0 are the minimum required versions that this repo runs on, but we always recommend using the latest version of Node.js.

Steps

1. git clone https://github.com/swagger-api/swagger-ui.git
2. cd swagger-ui
3. npm install
4. npx husky init (optional)
5. npm run dev
6. Wait a bit
7. Open http://localhost:3200/

Using your own local api definition with local dev build

You can specify a local file in dev-helpers/dev-helper-initializer.js by changing the url parameter. This local file MUST be located in the dev-helpers directory or a subdirectory. As a convenience and best practice, we recommend that you create a subdirectory, dev-helpers/examples, which is already specified in .gitignore.

replace

url: "https://petstore.swagger.io/v2/swagger.json",

with

url: "./examples/your-local-api-definition.yaml",

Files in dev-helpers should NOT be committed to git. The exception is if you are fixing something in index.html, oauth2-redirect.html, dev-helper-initializer.js, or introducing a new support file.

Bonus points

• Swagger UI includes an ESLint rule definition. If you use a graphical editor, consider installing an ESLint plugin, which will point out syntax and style errors for you as you code.
  • The linter runs as part of the PR test sequence, so don't think you can get away with not paying attention to it!