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Version: 5.x

Authentication Plugin

What's 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:

file: ./htpasswd

also multiple plugins can be chained:

file: ./htpasswd
foo: bar
bar: foo
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?

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.


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;
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

Since v4.0.0

apiJWTmiddleware was introduced on PR#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.

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

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

If the authentication fails

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

callback(null, false);
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

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

If adduser success

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

callback(null, true);
If adduser fails

Any other action different than success must return an error.

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

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


changePassword callback

If the request is successful

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

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

callback(null, user);
If the request fails

Any other action different than success must return an error.

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

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


allow_access, allow_publish, or allow_unpublish callback

These methods aims to allow or deny trigger some actions.

If the request success

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

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

callback(null, isAllowed)
If the request fails

Any other action different than success must return an error.

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

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


Generate an authentication 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? 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
? 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/
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

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:

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

Have you developed a new plugin? Add it here !