Add UTM Parameters to Optimizely CMS (Episerver) Forms

UTMParametersDataSource.cs

using EPiServer.Forms.Core.VisitorData;
using EPiServer.ServiceLocation;
using Microsoft.Extensions.Primitives;

namespace FormsFun.Business.Forms;

[ServiceConfiguration(ServiceType = typeof(IVisitorDataSource))]
public class UTMParametersDataSource(IHttpContextAccessor httpContextAccessor, ILogger<UTMParametersDataSource> logger) : IVisitorDataSource
{
    //Remember to add services.AddHttpContextAccessor() in your startup / DI registration.

    private readonly IHttpContextAccessor _httpContextAccessor = httpContextAccessor ?? throw new ArgumentNullException(nameof(httpContextAccessor));
    private readonly ILogger _logger = logger ?? throw new ArgumentNullException(nameof(logger));

    public void SetData(ref object visitorData, string property)
    {
        var ctx = _httpContextAccessor?.HttpContext;
        if (ctx != null)
        {
            if (ctx.Request.Query[property] != StringValues.Empty)
            {
                visitorData = ctx.Request.Query[property].ToString();
                return;
            }
        }
        else
        {
            _logger.LogWarning("Unable to get HttpContext when trying to get UTM parameters for form submission");
        }
        visitorData = null;
    }

    public bool ClientSideMode => false;

    public string DataSourceName => "UTM Parameters";

    public IEnumerable<KeyValuePair<string, string>> GetProperties()
    {
        List<KeyValuePair<string, string>> rt = new List<KeyValuePair<string, string>>();
        rt.Add(new KeyValuePair<string, string>("utm_source", "UTM Source"));
        rt.Add(new KeyValuePair<string, string>("utm_medium", "UTM Medium"));
        rt.Add(new KeyValuePair<string, string>("utm_campaign", "UTM Campaign"));
        rt.Add(new KeyValuePair<string, string>("utm_term", "UTM Term"));
        return rt;
    }

    public async Task<object> SetDataAsync(string property)
    {
        object visitorData = null;
        SetData(ref visitorData, property);
        return visitorData;
    }
}