Add APIKey authentication

Program.cs

@@ -1,33 +1,64 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Data.Sqlite;
+using TodoApi.Helpers;
 using TodoApi.Models;
+using Microsoft.OpenApi.Models;
 
 var builder = WebApplication.CreateBuilder(args);
 
 // Add services to the container.
 builder.Services.AddControllers();
 
+//Read the SQLite connection string from config file and add a DBContext
 var connectionString = new SqliteConnectionStringBuilder(builder.Configuration.GetConnectionString("TodoDatabase"))
 {
     Mode = SqliteOpenMode.ReadWriteCreate
 }.ToString();
-builder.Services.AddDbContext<TodoContext>(options =>
-    options.UseSqlite(connectionString));
+builder.Services.AddDbContext<TodoContext>(options => options.UseSqlite(connectionString));
+
+//setup APIKey validation using APIKeys from config file
+var apiKeys = builder.Configuration.GetSection("Authentication").GetValue<List<string>>("APIKeys");
+builder.Services.AddSingleton<IApiKeyValidator, ApiKeyValidator>(_ => new ApiKeyValidator(apiKeys));
 
 // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
 builder.Services.AddEndpointsApiExplorer();
-builder.Services.AddSwaggerGen();
+builder.Services.AddSwaggerGen(c =>
+{
+    c.SwaggerDoc("v1", new OpenApiInfo { Title = "ServiceName", Version = "1" });
+    c.AddSecurityDefinition("ApiKey", new OpenApiSecurityScheme
+    {
+        Name = "X-API-KEY",
+        In = ParameterLocation.Header,
+        Type = SecuritySchemeType.ApiKey,
+        Description = "Authorization by X-API-KEY inside request's header",
+        Scheme = "ApiKeyScheme"
+    });
+
+    var key = new OpenApiSecurityScheme()
+    {
+        Reference = new OpenApiReference
+        {
+            Type = ReferenceType.SecurityScheme,
+            Id = "ApiKey"
+        },
+        In = ParameterLocation.Header
+    };
+
+    var requirement = new OpenApiSecurityRequirement { { key, new List<string>() } };
+
+    c.AddSecurityRequirement(requirement);
+});
 
 var app = builder.Build();
 
 // Configure the HTTP request pipeline.
 // if (app.Environment.IsDevelopment())
 // {
-    app.UseSwagger();
-    app.UseSwaggerUI();
+app.UseSwagger();
+app.UseSwaggerUI();
 // }
 
-app.UseHttpsRedirection();
+app.UseAuthentication();
 
 app.UseAuthorization();