Initial service

Author: BenjaminMichaelis

Directory.Packages.props

@@ -16,7 +16,8 @@
     <PackageVersion Include="ContentFeedNuget" Version="$(ToolingPackagesVersion)" />
   </ItemGroup>
   <ItemGroup>
-    <PackageVersion Include="Microsoft.AspNetCore.Components" Version="9.0.1" />
+    <PackageVersion Include="Sqids" Version="3.1.0" />
+    <PackageVersion Include="Microsoft.EntityFrameworkCore.Sqlite" Version="8.0.8" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.8.0" />
     <PackageVersion Include="Microsoft.CodeAnalysis.Common" Version="4.8.0" />
     <PackageVersion Include="EssentialCSharp.Shared.Models" Version="$(ToolingPackagesVersion)" />

EssentialCSharp.Web/EssentialCSharp.Web.csproj

@@ -33,6 +33,7 @@
     <PackageReference Include="Newtonsoft.Json" />
     <PackageReference Include="Microsoft.VisualStudio.Azure.Containers.Tools.Targets" />
     <PackageReference Include="Octokit" />
+    <PackageReference Include="Sqids" />
   </ItemGroup>
   <ItemGroup>
     <Content Update="wwwroot\images\00mindmap.svg">

EssentialCSharp.Web/Program.cs

@@ -8,7 +8,8 @@
 using Microsoft.AspNetCore.HttpOverrides;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Identity.UI.Services;
-using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore;
+using Sqids;
 
 namespace EssentialCSharp.Web;
 
@@ -104,8 +105,14 @@ private static void Main(string[] args)
         builder.Services.AddRazorPages();
         builder.Services.AddCaptchaService(builder.Configuration.GetSection(CaptchaOptions.CaptchaSender));
         builder.Services.AddSingleton<ISiteMappingService, SiteMappingService>();
-        builder.Services.AddHostedService<DatabaseMigrationService>();
-
+        builder.Services.AddHostedService<DatabaseMigrationService>();
+        builder.Services.AddSingleton(new SqidsEncoder<int>(new()
+        {
+            // This is a shuffled version of the default alphabet so the id's are at least unique to this site.
+            // This being open source, it will be easy to decode the ids, but these id's are not meant to be secure.
+            Alphabet = "imx4BSz2Ys7GZLXDqT5IAkUOEnyvwbPKJtp13NWdeuH6rFfRhCcQogjaM8V09l",
+            MinLength = 10,
+        }));
 
         if (!builder.Environment.IsDevelopment())
         {

EssentialCSharp.Web/Services/ReferrerService.cs

@@ -0,0 +1,43 @@
+using Sqids;
+
+namespace EssentialCSharp.Web.Services;
+
+public class ReferrerService(SqidsEncoder<int> sqids)
+{
+    public string GenerateReferrerLink(string baseUrl, string userId)
+    {
+        string referrerId = sqids.Encode(1, 2, 3);
+        string referrerLink = $"{baseUrl}?referrerId={referrerId}";
+
+        // Store the referrerId and userId in the database for tracking
+        SaveReferrerIdToDatabase(userId, referrerId);
+
+        return referrerLink;
+    }
+
+    private void SaveReferrerIdToDatabase(string userId, string referrerId)
+    {
+        // Implement your database logic here
+    }
+
+    /// <summary>
+    /// Track the referral in the database.
+    /// </summary>
+    /// <param name="referrerId">The referrer ID to track.</param>
+    /// <returns>True if the referral was successfully tracked, otherwise false.</returns>
+    public bool TrackReferral(string referrerId)
+    {
+        // Implement your logic to track the referral in the database
+
+        if (sqids.Decode(referrerId) is [var decodedId] &&
+    referrerId == sqids.Encode(decodedId))
+        {
+            // `incomingId` decodes into a single number and is canonical, here you can safely proceed with the rest of the logic
+        }
+        else
+        {
+            // consider `incomingId` invalid — e.g. respond with 404
+        }
+        IReadOnlyList<int> numbers = sqids.Decode(referrerId); // [1, 2, 3]
+    }
+}