solved issue#3 ApiKey authentication and authorization with database support

EmailManager.sln

@@ -16,6 +16,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EmailManager.Shared", "src\
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EmailManager.BusinessLayer", "src\EmailManager.BusinessLayer\EmailManager.BusinessLayer.csproj", "{D7DF698B-95A0-4515-A88F-65DA674E97F3}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EmailManager.DataAccessLayer", "src\EmailManager.DataAccessLayer\EmailManager.DataAccessLayer.csproj", "{EEA8A36B-9EA6-42B5-A371-0E406A48E3FE}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -34,6 +36,10 @@ Global
 		{D7DF698B-95A0-4515-A88F-65DA674E97F3}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{D7DF698B-95A0-4515-A88F-65DA674E97F3}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{D7DF698B-95A0-4515-A88F-65DA674E97F3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{EEA8A36B-9EA6-42B5-A371-0E406A48E3FE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{EEA8A36B-9EA6-42B5-A371-0E406A48E3FE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{EEA8A36B-9EA6-42B5-A371-0E406A48E3FE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{EEA8A36B-9EA6-42B5-A371-0E406A48E3FE}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

src/EmailManager.BusinessLayer/Authentication/SubscriptionValidator.cs

@@ -0,0 +1,32 @@
+using System.Security.Claims;
+using EmailManager.DataAccessLayer;
+using Microsoft.EntityFrameworkCore;
+using SimpleAuthentication.ApiKey;
+
+namespace EmailManager.BusinessLayer.Authentication;
+
+public class SubscriptionValidator(ApplicationDbContext dbContext, TimeProvider timeProvider) : IApiKeyValidator
+{
+    public async Task<ApiKeyValidationResult> ValidateAsync(string apiKey)
+    {
+        var subscription = await dbContext.Subscriptions.FirstOrDefaultAsync(s => s.ApiKey == apiKey);
+        if (subscription is null)
+        {
+            return ApiKeyValidationResult.Fail("API key is invalid");
+        }
+
+        var now = timeProvider.GetUtcNow();
+        if (subscription.ValidFrom > now || subscription.ValidTo < now)
+        {
+            return ApiKeyValidationResult.Fail("API key is expired");
+        }
+
+        var claims = new List<Claim>
+        {
+            new("requests_per_window", subscription.RequestsPerWindow.ToString()),
+            new("window_minutes", subscription.WindowMinutes.ToString())
+        };
+
+        return ApiKeyValidationResult.Success(subscription.UserName, claims);
+    }
+}

src/EmailManager.BusinessLayer/EmailManager.BusinessLayer.csproj

@@ -13,9 +13,11 @@
     <ItemGroup>
       <PackageReference Include="FluentValidation" Version="12.0.0" />
       <PackageReference Include="MailKit" Version="4.13.0" />
+      <PackageReference Include="SimpleAuthenticationTools.Abstractions" Version="3.0.11" />
     </ItemGroup>
 
     <ItemGroup>
+        <ProjectReference Include="..\EmailManager.DataAccessLayer\EmailManager.DataAccessLayer.csproj" />
         <ProjectReference Include="..\EmailManager.Shared\EmailManager.Shared.csproj" />
     </ItemGroup>
 

src/EmailManager.DataAccessLayer/ApplicationDbContext.cs

@@ -0,0 +1,57 @@
+using System.Reflection;
+using EmailManager.DataAccessLayer.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Configuration;
+
+namespace EmailManager.DataAccessLayer;
+
+public class ApplicationDbContext(DbContextOptions<ApplicationDbContext> options, IConfiguration configuration) : DbContext(options)
+{
+    public DbSet<Subscription> Subscriptions { get; set; }
+
+    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+    {
+        base.OnConfiguring(optionsBuilder);
+
+        var administratorUserName = configuration.GetValue<string>("AppSettings:AdministratorUserName")!;
+        var administratorApiKey = configuration.GetValue<string>("AppSettings:AdministratorApiKey")!;
+
+        optionsBuilder.UseSeeding((context, _) =>
+        {
+            var subscription = context.Set<Subscription>().FirstOrDefault(s => s.UserName == administratorUserName);
+            CheckSubscription(context, subscription, administratorUserName, administratorApiKey);
+
+            context.SaveChanges();
+        });
+
+        optionsBuilder.UseAsyncSeeding(async (context, _, cancellationToken) =>
+        {
+            var subscription = await context.Set<Subscription>().FirstOrDefaultAsync(s => s.UserName == administratorUserName, cancellationToken: cancellationToken);
+            CheckSubscription(context, subscription, administratorUserName, administratorApiKey);
+
+            await context.SaveChangesAsync(cancellationToken);
+        });
+
+        static void CheckSubscription(DbContext context, Subscription? subscription, string administratorUserName, string administratorApiKey)
+        {
+            if (subscription is null)
+            {
+                context.Add(new Subscription
+                {
+                    UserName = administratorUserName,
+                    ApiKey = administratorApiKey,
+                    RequestsPerWindow = 10,
+                    WindowMinutes = 1,
+                    ValidFrom = DateTimeOffset.MinValue,
+                    ValidTo = DateTimeOffset.MaxValue
+                });
+            }
+        }
+    }
+
+    protected override void OnModelCreating(ModelBuilder modelBuilder)
+    {
+        modelBuilder.ApplyConfigurationsFromAssembly(Assembly.GetExecutingAssembly());
+        base.OnModelCreating(modelBuilder);
+    }
+}

src/EmailManager.DataAccessLayer/Configurations/SubscriptionConfiguration.cs

@@ -0,0 +1,21 @@
+using EmailManager.DataAccessLayer.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace EmailManager.DataAccessLayer.Configurations;
+
+internal class SubscriptionConfiguration : IEntityTypeConfiguration<Subscription>
+{
+    public void Configure(EntityTypeBuilder<Subscription> builder)
+    {
+        builder.ToTable("Subscriptions");
+        builder.HasKey(e => e.Id);
+        builder.Property(e => e.Id).HasDefaultValueSql("(newsequentialid())");
+
+        builder.HasIndex(e => e.ApiKey, "IX_Subscriptions_ApiKey").IsUnique();
+        builder.HasIndex(e => e.UserName, "IX_Subscriptions_UserName").IsUnique();
+
+        builder.Property(e => e.ApiKey).HasMaxLength(512).IsUnicode(false);
+        builder.Property(e => e.UserName).HasMaxLength(255);
+    }
+}

src/EmailManager.DataAccessLayer/EmailManager.DataAccessLayer.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net9.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+    <ItemGroup>
+        <FrameworkReference Include="Microsoft.AspNetCore.App" />
+    </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="9.0.8" />
+  </ItemGroup>
+
+
+
+</Project>

src/EmailManager.DataAccessLayer/Entities/Subscription.cs

@@ -0,0 +1,18 @@
+namespace EmailManager.DataAccessLayer.Entities;
+
+public class Subscription
+{
+    public Guid Id { get; set; }
+
+    public string UserName { get; set; } = null!;
+
+    public string ApiKey { get; set; } = null!;
+
+    public DateTimeOffset ValidFrom { get; set; }
+
+    public DateTimeOffset ValidTo { get; set; }
+
+    public int RequestsPerWindow { get; set; }
+
+    public int WindowMinutes { get; set; }
+}

src/EmailManager.DataAccessLayer/Migrations/20250905161309_Initial.cs

@@ -0,0 +1,51 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace EmailManager.DataAccessLayer.Migrations
+{
+    /// <inheritdoc />
+    public partial class Initial : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Subscriptions",
+                columns: table => new
+                {
+                    Id = table.Column<Guid>(type: "uniqueidentifier", nullable: false, defaultValueSql: "(newsequentialid())"),
+                    UserName = table.Column<string>(type: "nvarchar(255)", maxLength: 255, nullable: false),
+                    ApiKey = table.Column<string>(type: "varchar(512)", unicode: false, maxLength: 512, nullable: false),
+                    ValidFrom = table.Column<DateTimeOffset>(type: "datetimeoffset", nullable: false),
+                    ValidTo = table.Column<DateTimeOffset>(type: "datetimeoffset", nullable: false),
+                    RequestsPerWindow = table.Column<int>(type: "int", nullable: false),
+                    WindowMinutes = table.Column<int>(type: "int", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Subscriptions", x => x.Id);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Subscriptions_ApiKey",
+                table: "Subscriptions",
+                column: "ApiKey",
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Subscriptions_UserName",
+                table: "Subscriptions",
+                column: "UserName",
+                unique: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "Subscriptions");
+        }
+    }
+}

src/EmailManager.DataAccessLayer/Migrations/ApplicationDbContextModelSnapshot.cs

@@ -0,0 +1,68 @@
+// <auto-generated />
+using System;
+using EmailManager.DataAccessLayer;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+#nullable disable
+
+namespace EmailManager.DataAccessLayer.Migrations
+{
+    [DbContext(typeof(ApplicationDbContext))]
+    partial class ApplicationDbContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "9.0.8")
+                .HasAnnotation("Relational:MaxIdentifierLength", 128);
+
+            SqlServerModelBuilderExtensions.UseIdentityColumns(modelBuilder);
+
+            modelBuilder.Entity("EmailManager.DataAccessLayer.Entities.Subscription", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("uniqueidentifier")
+                        .HasDefaultValueSql("(newsequentialid())");
+
+                    b.Property<string>("ApiKey")
+                        .IsRequired()
+                        .HasMaxLength(512)
+                        .IsUnicode(false)
+                        .HasColumnType("varchar(512)");
+
+                    b.Property<int>("RequestsPerWindow")
+                        .HasColumnType("int");
+
+                    b.Property<string>("UserName")
+                        .IsRequired()
+                        .HasMaxLength(255)
+                        .HasColumnType("nvarchar(255)");
+
+                    b.Property<DateTimeOffset>("ValidFrom")
+                        .HasColumnType("datetimeoffset");
+
+                    b.Property<DateTimeOffset>("ValidTo")
+                        .HasColumnType("datetimeoffset");
+
+                    b.Property<int>("WindowMinutes")
+                        .HasColumnType("int");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex(new[] { "ApiKey" }, "IX_Subscriptions_ApiKey")
+                        .IsUnique();
+
+                    b.HasIndex(new[] { "UserName" }, "IX_Subscriptions_UserName")
+                        .IsUnique();
+
+                    b.ToTable("Subscriptions", (string)null);
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}