verdaccio/website/versioned_docs/version-6.x/plugin-auth.md

---
id: plugin-auth
title: 'Authentication Plugin'
---

## What's an authentication plugin? {#whats-an-authentication-plugin}

Is a sort plugin that allows to handle who access or publish to a specific package. By default the `htpasswd` is built-in, but can
easily be replaced by your own.

## Getting Started

The authentication plugins are defined in the `auth:` section, as follows:

```yaml
auth:
  htpasswd:
    file: ./htpasswd
```

also multiple plugins can be chained:

```yaml
auth:
  htpasswd:
    file: ./htpasswd
  anotherAuth:
    foo: bar
    bar: foo
  lastPlugin:
    foo: bar
    bar: foo
```

> If one of the plugin in the chain is able to resolve the request, the next ones will be ignored.

## How do the authentication plugin works? {#how-do-the-authentication-plugin-works}

Basically we have to return an object with a single method called `authenticate` that will receive 3 arguments (`user, password, callback`).

On each request, `authenticate` will be triggered and the plugin should return the credentials, if the `authenticate` fails, it will fallback to the `$anonymous` role by default.

### API {#api}

```typescript
interface IPluginAuth<T> extends IPlugin<T> {
  authenticate(user: string, password: string, cb: AuthCallback): void;
  adduser?(user: string, password: string, cb: AuthCallback): void;
  changePassword?(user: string, password: string, newPassword: string, cb: AuthCallback): void;
  allow_publish?(user: RemoteUser, pkg: AllowAccess & PackageAccess, cb: AuthAccessCallback): void;
  allow_access?(user: RemoteUser, pkg: AllowAccess & PackageAccess, cb: AuthAccessCallback): void;
  allow_unpublish?(
    user: RemoteUser,
    pkg: AllowAccess & PackageAccess,
    cb: AuthAccessCallback
  ): void;
  apiJWTmiddleware?(helpers: any): Function;
}
```

> Only `adduser`, `allow_access`, `apiJWTmiddleware`, `allow_publish` and `allow_unpublish` are optional, verdaccio provide a fallback in all those cases.

#### `apiJWTmiddleware` method {#apijwtmiddleware-method}

Since `v4.0.0`

`apiJWTmiddleware` was introduced on [PR#1227](https://github.com/verdaccio/verdaccio/pull/1227) in order to have full control of the token handler, overriding this method will disable `login/adduser` support. We recommend don't implement this method unless is totally necessary. See a full example [here](https://github.com/verdaccio/verdaccio/pull/1227#issuecomment-463235068).

## What should I return in each of the methods? {#what-should-i-return-in-each-of-the-methods}

Verdaccio relies on `callback` functions at time of this writing. Each method should call the method and what you return is important, let's review how to do it.

### `authentication` callback {#authentication-callback}

Once the authentication has been executed there is 2 options to give a response to `verdaccio`.

##### If the authentication fails {#if-the-authentication-fails}

If the auth was unsuccessful, return `false` as the second argument.

```typescript
callback(null, false);
```

##### If the authentication success {#if-the-authentication-success}

The auth was successful.

`groups` is an array of strings where the user is part of.

```
 callback(null, groups);
```

##### If the authentication produce an error {#if-the-authentication-produce-an-error}

The authentication service might fails, and you might want to reflect that in the user response, eg: service is unavailable.

```
 import { getInternalError } from '@verdaccio/commons-api';

 callback(getInternalError('something bad message), null);
```

> A failure on login is not the same as service error, if you want to notify user the credentials are wrong, just return `false` instead string of groups. The behaviour mostly depends of you.

### `adduser` callback {#adduser-callback}

##### If adduser success {#if-adduser-success}

If the service is able to create an user, return `true` as the second argument.

```typescript
callback(null, true);
```

##### If adduser fails {#if-adduser-fails}

Any other action different than success must return an error.

```typescript
import { getConflict } from '@verdaccio/commons-api';

const err = getConflict('maximum amount of users reached');

callback(err);
```

### `changePassword` callback {#changepassword-callback}

##### If the request is successful {#if-the-request-is-successful}

If the service is able to create an user, return `true` as the second argument.

```typescript
const user = serviceUpdatePassword(user, password, newPassword);

callback(null, user);
```

##### If the request fails {#if-the-request-fails}

Any other action different than success must return an error.

```typescript
import { getNotFound } from '@verdaccio/commons-api';

const err = getNotFound('user not found');

callback(err);
```

### `allow_access`, `allow_publish`, or `allow_unpublish` callback {#allow_access-allow_publish-or-allow_unpublish-callback}

These methods aims to allow or deny trigger some actions.

##### If the request success {#if-the-request-success}

If the service is able to create an user, return a `true` as the second argument.

```typescript

allow_access(user: RemoteUser, pkg: PackageAccess, cb: Callback): void {
  const isAllowed: boolean = checkAction(user, pkg);

  callback(null, isAllowed)
}
```

##### If the request fails {#if-the-request-fails-1}

Any other action different than success must return an error.

```typescript
import { getNotFound } from '@verdaccio/commons-api';

const err = getForbidden('not allowed to access package');

callback(err);
```

## Generate an authentication plugin {#generate-an-authentication-plugin}

For detailed info check our [plugin generator page](plugin-generator). 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? service-name
? Select Language typescript
? What kind of plugin you want to create? auth
? Please, describe your plugin awesome auth plugin
? GitHub username or organization myusername
? Author's Name Juan Picado
? Author's Email jotadeveloper@gmail.com
? Key your keywords (comma to split) verdaccio,plugin,auth,awesome,verdaccio-plugin
   create verdaccio-plugin-authservice-name/package.json
   create verdaccio-plugin-authservice-name/.gitignore
   create verdaccio-plugin-authservice-name/.npmignore
   create verdaccio-plugin-authservice-name/jest.config.js
   create verdaccio-plugin-authservice-name/.babelrc
   create verdaccio-plugin-authservice-name/.travis.yml
   create verdaccio-plugin-authservice-name/README.md
   create verdaccio-plugin-authservice-name/.eslintrc
   create verdaccio-plugin-authservice-name/.eslintignore
   create verdaccio-plugin-authservice-name/src/index.ts
   create verdaccio-plugin-authservice-name/index.ts
   create verdaccio-plugin-authservice-name/tsconfig.json
   create verdaccio-plugin-authservice-name/types/index.ts
   create verdaccio-plugin-authservice-name/.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-service-name
➜ cat package.json

  {
  "name": "verdaccio-plugin-service-name",
  "version": "0.0.1",
  "description": "awesome auth plugin",
  ...
```

## Full implementation ES5 example {#full-implementation-es5-example}

```javascript
function Auth(config, stuff) {
  var self = Object.create(Auth.prototype);
  self._users = {};

  // config for this module
  self._config = config;

  // verdaccio logger
  self._logger = stuff.logger;

  // pass verdaccio logger to ldapauth
  self._config.client_options.log = stuff.logger;

  return self;
}

Auth.prototype.authenticate = function (user, password, callback) {
  var LdapClient = new LdapAuth(self._config.client_options);
  ....
  LdapClient.authenticate(user, password, function (err, ldapUser) {
    ...
    var groups;
     ...
    callback(null, groups);
  });
};

module.exports = Auth;
```

And the configuration will looks like:

```yaml
auth:
  htpasswd:
    file: ./htpasswd
```

Where `htpasswd` is the sufix of the plugin name. eg: `verdaccio-htpasswd` and the rest of the body would be the plugin configuration params.

### List Community Authentication Plugins {#list-community-authentication-plugins}

- [verdaccio-bitbucket](https://github.com/idangozlan/verdaccio-bitbucket): Bitbucket authentication plugin for verdaccio.
- [verdaccio-bitbucket-server](https://github.com/oeph/verdaccio-bitbucket-server): Bitbucket Server authentication plugin for verdaccio.
- [verdaccio-ldap](https://www.npmjs.com/package/verdaccio-ldap): LDAP auth plugin for verdaccio.
- [verdaccio-active-directory](https://github.com/nowhammies/verdaccio-activedirectory): Active Directory authentication plugin for verdaccio
- [verdaccio-gitlab](https://github.com/bufferoverflow/verdaccio-gitlab): use GitLab Personal Access Token to authenticate
- [verdaccio-gitlab-ci](https://github.com/lab360-ch/verdaccio-gitlab-ci): Enable GitLab CI to authenticate against verdaccio.
- [verdaccio-htpasswd](https://github.com/verdaccio/verdaccio-htpasswd): Auth based on htpasswd file plugin (built-in) for verdaccio
- [verdaccio-github-oauth](https://github.com/aroundus-inc/verdaccio-github-oauth): Github oauth authentication plugin for verdaccio.
- [verdaccio-github-oauth-ui](https://github.com/n4bb12/verdaccio-github-oauth-ui): GitHub OAuth plugin for the verdaccio login button.
- [verdaccio-groupnames](https://github.com/deinstapel/verdaccio-groupnames): Plugin to handle dynamic group associations utilizing `$group` syntax. Works best with the ldap plugin.
- [verdaccio-sqlite](https://github.com/bchanudet/verdaccio-sqlite): SQLite Authentication plugin for Verdaccio
- [verdaccio-okta-auth](https://github.com/hogarthww-labs/verdaccio-okta-auth) Verdaccio Okta Auth
- [verdaccio-azure-ad-login](https://github.com/IhToN/verdaccio-azure-ad-login) Let your users authenticate into Verdaccio via Azure AD OAuth 2.0 API
- [verdaccio-auth-gitlab](https://github.com/pfdgithub/verdaccio-auth-gitlab) Verdaccio authentication plugin by gitlab personal access tokens.

**Have you developed a new plugin? Add it here !**