ASP.NET Core 5.0 - Preferred UserAgents

This article will describe how to capture a user agent string and store it with a preferred property. I will assume you have downloaded the ASP.NET Core 5.0 - Homegrown Analytics Project or created a new ASP.NET Core 5.0 Razor Pages project. See Tutorial: Get started with Razor Pages in ASP.NET Core.

I have upgraded the PageHit entity's UserAgent property from a string to an int. The UserAgentId relates to a child UserAgent entity with a Preferred property.

Entities > UserAgent.cs:

public class UserAgent
{
    [Key]
    public int Id { get; set; }
    [Required]
    [Display(Name = "UserAgent")]
    [StringLength(512)]
    public string UAString { get; set; }
    public bool Preferred { get; set; }
    public DateTimeOffset CreateDate { get; set; }
}

The AnalyticsMiddleware and AnalyticsServices creates a new UserAgent if it does not exist. The initial migration and CreateAnalyticsSchema SQL scripts create a default UserAgent with the primary Id property set to 1. If the AnalyticsMiddleware encounters an issue, the default UserAgent is employed.

I developed a UserAgents page which displays the UserAgent's PageHits count and provides the functions to add or remove the preferred status.

Rather than trying to detect robot page hits, I can filter on Preferred UserAgents.