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Middleware Plugin

What's an Middleware Plugin?#

Middleware plugins have the capability to modify the API (web and cli) layer, either adding new endpoints or intercepting requests.


interface IPluginMiddleware<T> extends IPlugin<T> {  register_middlewares(app: any, auth: IBasicAuth<T>, storage: IStorageManager<T>): void;}


The method provide full access to the authentification and storage via auth and storage. app is the express application that allows you to add new endpoints.

public register_middlewares(    app: Application,    auth: IBasicAuth<CustomConfig>,    storage: IStorageManager<CustomConfig>  ): void {    const router = Router();      '/custom-endpoint',      (req: Request, res: Response & { report_error?: Function }, next: NextFunction): void => {        const encryptedString = auth.aesEncrypt(Buffer.from(, 'utf8'));        res.setHeader('X-Verdaccio-Token-Plugin', encryptedString.toString());        next();      }    );    app.use('/-/npm/something-new', router);  }

The auth and storage are instances and can be extended, but we don't recommend this approach unless is well founded.

A good example of a middleware plugin is the verdaccio-audit.

Generate an middleware plugin#

For detailed info check our plugin generator page. Run the yo command in your terminal and follow the steps.

➜ yo verdaccio-plugin
Just found a `.yo-rc.json` in a parent directory.Setting the project root at: /Users/user/verdaccio_yo_generator
     _-----_     ╭──────────────────────────╮    |       |    │        Welcome to        │    |--(o)--|    │ generator-verdaccio-plug │   `---------´   │   in plugin generator!   │    ( _´U`_ )    ╰──────────────────────────╯    /___A___\   /     |  ~  |   __'.___.'__ ´   `  |° ´ Y `
? What is the name of your plugin? custom-endpoint? Select Language typescript? What kind of plugin you want to create? middleware? Please, describe your plugin awesome middleware plugin? GitHub username or organization myusername? Author's Name Juan Picado? Author's Email Key your keywords (comma to split) verdaccio,plugin,middleware,awesome,verdaccio-plugin   create verdaccio-plugin-custom-endpoint/package.json   create verdaccio-plugin-custom-endpoint/.gitignore   create verdaccio-plugin-custom-endpoint/.npmignore   create verdaccio-plugin-custom-endpoint/jest.config.js   create verdaccio-plugin-custom-endpoint/.babelrc   create verdaccio-plugin-custom-endpoint/.travis.yml   create verdaccio-plugin-custom-endpoint/   create verdaccio-plugin-custom-endpoint/.eslintrc   create verdaccio-plugin-custom-endpoint/.eslintignore   create verdaccio-plugin-custom-endpoint/src/index.ts   create verdaccio-plugin-custom-endpoint/index.ts   create verdaccio-plugin-custom-endpoint/tsconfig.json   create verdaccio-plugin-custom-endpoint/types/index.ts   create verdaccio-plugin-custom-endpoint/.editorconfig
I'm all done. Running npm install for you to install the required dependencies. If this fails, try running the command yourself.

⸨ ░░░░░░░░░░░░░░░░░⸩ ⠋ fetchMetadata: sill pacote range manifest for @babel/plugin-syntax-jsx@^7.7.4 fetc

After the install finish, access to your project scalfold.

➜ cd verdaccio-plugin-auth-service-name➜ cat package.json
  {  "name": "verdaccio-plugin-custom-endpoint",  "version": "0.0.1",  "description": "awesome middleware plugin",  ...

The middleware are registrered after built-in endpoints, thus, it is not possible to override the implemented ones.

List Community Middleware Plugins#

  • verdaccio-audit: verdaccio plugin for npm audit cli support (built-in) (compatible since 3.x)

  • verdaccio-profile-api: verdaccio plugin for npm profile cli support and npm profile set password for verdaccio-htpasswd based authentificaton

  • verdaccio-https Verdaccio middleware plugin to redirect to https if x-forwarded-proto header is set

  • verdaccio-badges A verdaccio plugin to provide a version badge generator endpoint

  • verdaccio-openmetrics Verdaccio plugin exposing an OpenMetrics/Prometheus endpoint with health and traffic metrics

  • verdaccio-sentry sentry loggin errors

  • verdaccio-pacman Verdaccio Middleware Plugin to manage tags and versions of packages