Working with cookies

A cookie is a small piece of data that a website asks your browser to store on your computer or mobile device. The cookie allows the website to “remember” your actions or preferences over time.

Xperience provides an extensible framework, built around cookie levels, for manipulating cookies – from assigning specific levels of allowed cookies to users and contacts, to registering custom cookies and their corresponding cookie levels.

Setting the default cookie level

A site’s default cookie level determines which cookies the system stores in users’ browsers by default. To set the default cookie level:

1. Open Settings application and select the System category.
2. Under the Cookies heading, select a Default cookie level.
   • For an overview of individual cookie levels, see Cookie levels.
3. Click Save.

The system now uses the selected cookie level when evaluating which cookies should be stored in users’ browsers. 

Cookie levels

Xperience classifies cookies into several levels according to their purpose. The levels allow you to set cookie levels for users. The following are the default levels available in the cookie API (CMS.Helpers.CookieLevel class):

The numbers associated with each cookie level are integer constants, which allows you to further customize the granularity of available cookie levels. The levels ‘None’ and ‘All’ are set to an absolute value of 1000 to provide enough space for future Xperience updates or developer-specified custom levels.

Registering custom cookies

If your website uses any custom or third-party cookies, we recommend that you register them with an appropriate cookie level. Unregistered cookies are processed with the Visitor level by default.

When a visitor adjusts their allowed cookie level (for example by accepting or revoking a consent), the system automatically clears all cookies that have a higher level from the visitor’s browser. You may also encounter problems with custom or third-party cookies not being stored if your site’s System -> Default cookie level setting has a lower value than Visitor, for example when managing tracking consent.

To register custom cookies, you need to add custom code to your project. Call the CookieHelper.RegisterCookie method (available in the CMS.Helpers namespace of the Xperience API), with the following parameters:

• string name – the name of the cookie that you are registering.
• int level – an integer value representing the cookie level required to use the cookie. You can access the default level values in the CookieLevel enumeration.

To ensure that your cookies are recognized correctly, call the RegisterCookie method at the beginning of the application’s life cycle – either during the initialization of a custom module class, or within suitable startup code if you are using the Xperience API in an external application.

var cookieOptions = new CookieOptions
{
    IsEssential = true
};

// Adds the cookie to the response cookie collection
HttpContext.Response.Cookies.Append("cookieName", "cookieValue", cookieOptions);

Example

The following example demonstrates how to register a custom cookie named CustomCookie with the Essential cookie level:

1. Open the Xperience live site project in Visual Studio.

2. Create a custom module class.

   • We recommend adding the class into a custom Class Library project within the solution.

3. Override the module’s OnInit method and call the CookieHelper.RegisterCookie method.

   Copy

   
   
   
    using CMS;
   
    using CMS.DataEngine;
    using CMS.Helpers;
   
    // Registers the custom module into the system
    [assembly: RegisterModule(typeof(CustomInitializationModule))]
   
    public class CustomInitializationModule : Module
    {
        // Module class constructor, the system registers the module under the name "CustomInit"
        public CustomInitializationModule()
            : base("CustomInit")
        {
        }
   
        // Contains initialization code that is executed when the application starts
        protected override void OnInit()
        {
            base.OnInit();
   
            // Registers the "CustomCookie" with the 'Essential' cookie level
            // Ensures that the cookie is preserved for visitors who change their allowed cookie level below 'Visitor'
            CookieHelper.RegisterCookie("CustomCookie", CookieLevel.Essential);
        }
    }
   
   
    

The CustomCookie is now registered and can be used by visitors with the Essential and above cookie level (based on your site’s default cookie level, the users’ preferred cookie level, or other custom actions such as consent agreements).

Setting cookies

You can use the Xperience API to create and set custom cookies into a user’s browser. Call the CookieHelper.SetValue method within the scope of an HTTP request:

using CMS.Helpers;
...

// Saves a custom cookie named "CustomCookie" to the current visitor's browser,
// with "CustomValue" as its value and an expiration time of 1 year
CookieHelper.SetValue("CustomCookie", "CustomValue", DateTime.Now.AddYears(1));

Cookies set using CookieHelper use the Lax SameSite mode by default. To specify a different SameSite mode, add an additional parameter with a value from the CMS.Base.SameSiteMode enumeration when setting the cookie:

CookieHelper.SetValue("CustomCookie", "CustomValue", DateTime.Now.AddYears(1), sameSiteMode: SameSiteMode.Strict);

// Adds the Secure attribute to the cookie with 'SameSite=None'. 
// The user agent will include the cookie in an HTTP request only if the request is transmitted over a secure channel (typically HTTPS).
CookieHelper.SetValue("CustomCookie", "CustomValue", DateTime.Now.AddYears(1), sameSiteMode: SameSiteMode.None, secure: true);

Allowing users to choose their preferred cookie level

In compliance with the cookie law, you can allow users to select their preferred cookie level. Use the SetCurrentCookieLevel method provided by the ICurrentCookieLevelProvider service.

The following code snippets demonstrate the usage of the ICurrentCookieLevelProvider API on a basic example. The code allows users to set their preferred cookie level via a simple form.

using System.Web.Mvc;
using System.Collections.Generic;

using CMS.Helpers;

public class CookieLevelController : Controller
{
    private readonly ICurrentCookieLevelProvider cookieLevelService;

    // Initializes instances of required services using dependency injection
    public CookieLevelController(ICurrentCookieLevelProvider cookieLevelService)
    {
        this.cookieLevelService = cookieLevelService;
    }

    public ActionResult Index()
    {
        // Creates a list with the three default levels of cookie compliance relevant for site visitors.
        // The CookieLevel class is used to directly extract integer values corresponding to each cookie level
        // so that no additional mapping is necessary.
        var cookieLevels = new List<object>() {
                new { label = "Essential", value = CookieLevel.Essential },
                new { label = "Visitor", value = CookieLevel.Visitor },
                new { label = "All", value = CookieLevel.All }
            };

        return View(new SelectList(cookieLevels, "value", "label"));
    }

    // Sets the cookie level for the current user
    // The value passed into the action from the corresponding view directly corresponds to one of the system's 
    // cookie levels thanks to the CookieLevel class.
    [HttpPost]
    public ActionResult SetCookieLevel(int SelectedValue)
    {
        // Sets the cookie level for the current user to the level corresponding to the provided value
        cookieLevelService.SetCurrentCookieLevel(SelectedValue);

        return RedirectToAction(nameof(Index));
    }
}

The corresponding view contains a drop-down selectors that allows users to select the desired level of cookies.

@model SelectList

@using (Html.BeginForm("SetCookieLevel", "CookieLevel", FormMethod.Post))
{
    @Html.DropDownListFor(x => x.SelectedValue, Model)
    <input type="submit" value="Select" />
}