# Session Storage

It is often useful to store information relevant to a user of the app for the duration of that usage session. For example the user may choose to want to save a option or be remembered as logged in. This information can either be stored client side or server side and Quart provides a system to store the information client side via Secure Cookie Sessions.

## Secure Cookie Sessions

Secure Cookie Sessions store the session information on the Cookie in plain text with a signature to ensure that the information is not altered by the client. They can be used in Quart so long as the `secret_key` is set to a secret value.

An example usage to store a users colour preference would be,

    from quart import session
    ...

    @app.route('/')
    async def index():
        return await render_template(
            'index.html',
            colour=session.get('colour', 'black'),
        )

    @app.route('/colour/', methods=['POST'])
    async def set_colour():
        ...
        session['colour'] = colour
        return redirect(url_for('index'))

## Permanent Sessions

The cookies used by default are not set to be permanent (deleted when the browser’s session ends) to have permanent cookies `session.permanent` must be `True` when the session is modified. To set this as the default use this snippet,

    @app.before_request
    def make_session_permanent():
        session.permanent = True

## WebSockets

Sessions can be used with WebSockets with an important caveat about cookies. A cookie can only be set on a HTTP response, and an accepted WebSocket connection cannot return a HTTP response. Therefore the default implementation, being based on cookies, will lose any modifications made during an accepted WebSocket connection.