---
outline: deep
---

# Authenticate Hook

The `authenticate` hook will use `params.authentication` of the service method call and run [authenticationService.authenticate()]().

## authenticate(... strategies)

## authenticate(options)

It should be used as a `before` hook and either takes a list of strategy names (using `app.service('authentication')` as the authentication service) or an object with `service` set to the authentication service name and `strategies` set to a list of strategy names to authenticate with:

```js
const { authenticate } = require('@feathersjs/authentication');

// Authenticate with `jwt` and `api-key` strategy
// using app.service('authentication') as the authentication service
app.service('messages').hooks({
  before: authenticate('jwt', 'api-key')
});

// Authenticate with `jwt` and `api-key` strategy
// using app.service('v1/authentication') as the authentication service
app.service('messages').hooks({
  before: authenticate({
    service: 'v1/authentication',
    strategies: [ 'jwt', 'api-key' ]
  })
});
```

The hook will

- Throw an error if the strategy fails
- Throw an error if no authentication information is set and it is an external call (`params.provider` is set) or do nothing if it is an internal call (`params.provider` is `undefined`)
- If successful, merge `params` with the return value of the authentication strategy

For example, a successful [JWT strategy](./jwt.md) authentication will set:

```js
params.authentication.payload // The decoded payload
params.authentication.strategy === 'jwt' // The strategy name
params.user // or params[entity] if entity is not `null`
```

In the following hooks and for the service method call.