!CHAPTER Foxx Sessions

Foxx provides some convenience methods to make working with sessions easier.

!SUBSECTION Activate sessions

Enables session features for the controller.

`controller.activateSessions(options)`

Once sessions have been activated, a *session* property will be added to the *request* object passed to route handlers defined on the controller, which will be a saved instance of the session model provided by the session storage.

If the option *autoCreateSession* has not explicitly been set to *false*, a new session will be created for users that do not yet have an active session.

If *type* is set to *"cookie"*, the session cookie will be updated after every route.

*Parameter*

* *options* (optional): an object with any of the following properties:
  * *sessionStorageApp* (optional): mount point of the session storage app to use. Default: *"/_system/sessions"*.
  * *type* (optional): sessions type, currently only *"cookie"* and *"header"* are supported. Default: *"cookie"*.
  * *cookie* (optional): an object with the following properties:
    * *name*: name of the session cookie if using cookie sessions. Default: *"sid"*.
    * *secret* (optional): secret string to sign session cookies with if using cookie sessions.
    * *algorithm* (optional): algorithm to sign session cookies with if using cookie sessions. Default: *"sha256"*.
  * *header* (optional): name of the session header if using header sessions. Default: *"X-Session-Id"*.
  * *jwt* (optional): whether the session ID should be wrapped in a JSON Web Token. Default: *false*.
  * *autoCreateSession* (optional): whether a session should always be created if none exists. Default: *true*.

If *cookie* is set to a string, its value will be used as the *cookie.name* instead.

Optionally *jwt* can be an object with any of the following values:

* *secret* (optional): secret string to sign session JSON Web Tokens with.
* *algorithm* (optional): algorithm to sign session JSON Web Tokens with. Default: *"HS256"* if a *secret* is provided, *"none"* otherwise.
* *verify* (optional): whether incoming session JSON Web Tokens should be verified. Default: *true*.

If *jwt* is set to a string, its value will be used as the *jwt.secret* instead.

Note that if the *jwt.algorithm* is explicitly set to any algorithm other than *"none"*, not providing a *jwt.secret* will raise an exception.

*Examples*

Example configuration for using signed cookies:

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  cookieName: 'sid',
  cookieSecret: 'secret',
  type: 'cookie'
});
```

Example configuration for using a header:

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  headerName: 'X-Session-Token',
  type: 'header'
});
```

Example configuration for using a JWT header:

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  headerName: 'X-Web-Token',
  jwt: 'keyboardcat',
  type: 'header'
});
```

Example configuration for using a JWT header with signature algorithm "none" (and no secret):

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  headerName: 'X-Web-Token',
  jwt: true,
  type: 'header'
});
```

Example configuration for using a JWT header with signature verification disabled:

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  headerName: 'X-Web-Token',
  jwt: {
    verify: false
  },
  type: 'header'
});
```

Example configuration for using signed JWT cookies:

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  cookieName: 'token',
  cookieSecret: 'secret',
  jwt: 'keyboardcat',
  type: 'cookie'
});
```

Example configuration for using unsigned cookies:

```js
var controller = new FoxxController(applicationContext);
controller.activateSessions({
  sessionStorageApp: '/_system/sessions',
  cookieName: 'sid',
  type: 'cookie'
});
```

!SUBSECTION Define a session destruction route

Defines a route that will destroy the session.

`controller.destroySession(path, options)`

Defines a route handler on the controller that destroys the session.

When using cookie sessions, this function will clear the session cookie (if *autoCreateSession* was disabled) or create a new session cookie, before calling the *after* function.

*Parameter*

* *path*: route path as passed to *controller.get*, *controller.post*, etc.
* *options* (optional): an object with any of the following properties:
  * *method* (optional): HTTP method to handle. Default: *"post"*.
  * *before* (optional): function to execute before the session is destroyed. Receives the same arguments as a regular route handler.
  * *after* (optional): function to execute after the session is destroyed. Receives the same arguments as a regular route handler. Default: a function that sends a *{"message": "logged out"}* JSON response.