feat: jwt token example

Controllers/WeatherForecastController.cs

@@ -1,21 +1,32 @@
+using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.IdentityModel.Tokens;
+using QuotifyBE.Controllers;
+using QuotifyBE.DTOs;
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using System.Text;
 
 namespace QuotifyBE.Controllers
 {
+
     [ApiController]
     [Route("[controller]")]
     public class WeatherForecastController : ControllerBase
     {
+
         private static readonly string[] Summaries = new[]
         {
             "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
         };
 
         private readonly ILogger<WeatherForecastController> _logger;
+        private readonly IConfiguration _appsettings;
 
-        public WeatherForecastController(ILogger<WeatherForecastController> logger)
+        public WeatherForecastController(ILogger<WeatherForecastController> logger, IConfiguration appsettings)
         {
             _logger = logger;
+            _appsettings = appsettings;
         }
 
         [HttpGet(Name = "GetWeatherForecast")]
@@ -29,5 +40,48 @@ namespace QuotifyBE.Controllers
             })
             .ToArray();
         }
+
+        [HttpPost("login")]
+        public IActionResult Login([FromBody] UserLoginDTO user)
+        {
+            if (user.Email == "admin" && user.Password == "password")
+            {
+                var token = GenerateJwtToken(user.Email);
+                return Ok(new { token });
+            }
+            return Unauthorized();
+        }
+
+        [HttpGet("some_values")]
+        [Authorize]
+        public IActionResult GetValues()
+        {
+            return Ok(new string[] { "value1", "value2" });
+        }
+
+        private string GenerateJwtToken(string username)
+        {
+            var claims = new[]
+            {
+                new Claim(JwtRegisteredClaimNames.Sub, username),
+                new Claim(JwtRegisteredClaimNames.Jti, Guid.NewGuid().ToString())
+            };
+
+            var key = new SymmetricSecurityKey(
+                Encoding.UTF8.GetBytes(_appsettings["JwtSecret"]!)
+                // won't be null here - otherwise Program.cs wouldn't start
+            );
+            var creds = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
+
+            var token = new JwtSecurityToken(
+                issuer: _appsettings["DomainName"]!,
+                audience: _appsettings["DomainName"]!,
+                claims: claims,
+                expires: DateTime.Now.AddDays(7),
+                signingCredentials: creds
+            );
+
+            return new JwtSecurityTokenHandler().WriteToken(token);
+        }
     }
 }

DTOs/UserLoginDTO.cs

@@ -0,0 +1,10 @@
+namespace QuotifyBE.DTOs;
+
+public record class UserLoginDTO
+{
+    required public string Email { get; set; }
+    required public string Password { get; set; }
+
+    // public UserLoginDTO() { }
+
+};

Program.cs

@@ -1,6 +1,9 @@
+using Microsoft.AspNetCore.Authentication.JwtBearer;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.IdentityModel.Tokens;
 using QuotifyBE.Data;
 using QuotifyBE.Entities;
+using System.Text;
 
 var builder = WebApplication.CreateBuilder(args);
 
@@ -9,7 +12,34 @@ var connectionString = builder.Configuration.GetConnectionString("DefaultConnect
 builder.Services.AddDbContext<ApplicationDbContext>(options =>
     options.UseNpgsql(connectionString));
 
+var JwtSecret = builder.Configuration["JwtSecret"]
+    ?? throw new InvalidOperationException("JWT token secret is not configured!!! Please configure JwtSecret in appsettings.json!");
+
+var DomainName = builder.Configuration["DomainName"]
+    ?? throw new InvalidOperationException("Domain name is not configured!!! Please configure DomainName in appsettings.json!");
+
+// Configure JWT authentication
+// https://medium.com/@solomongetachew112/jwt-authentication-in-net-8-a-complete-guide-for-secure-and-scalable-applications-6281e5e8667c
+builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
+    .AddJwtBearer(options =>
+    {
+        options.TokenValidationParameters = new TokenValidationParameters
+        {
+            ValidateIssuer = true,
+            ValidateAudience = true,
+            ValidateLifetime = true,
+            ValidateIssuerSigningKey = true,
+            ValidIssuer = DomainName,
+            ValidAudience = DomainName,
+            IssuerSigningKey = new SymmetricSecurityKey(
+                Encoding.UTF8.GetBytes(JwtSecret)
+            )
+        };
+    });
+
 // Add services to the container.
+builder.Services.AddAuthorization();
+builder.Services.AddSingleton(builder.Configuration);
 
 builder.Services.AddControllers();
 // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
@@ -28,6 +58,7 @@ if (app.Environment.IsDevelopment())
 
 app.UseHttpsRedirection();
 
+app.UseAuthentication();
 app.UseAuthorization();
 
 app.MapControllers();

QuotifyBE.csproj

@@ -11,6 +11,7 @@
 
   <ItemGroup>
     <PackageReference Include="EntityFramework" Version="6.5.1" />
+    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="8.0.18" />
     <PackageReference Include="Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore" Version="8.0.18" />
     <PackageReference Include="Microsoft.EntityFrameworkCore" Version="9.0.7" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.0.7">
@@ -27,4 +28,8 @@
     <PackageReference Include="Swashbuckle.AspNetCore" Version="9.0.3" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Folder Include="Mapping\" />
+  </ItemGroup>
+
 </Project>

appsettings.example.json

@@ -1,4 +1,6 @@
 {
+  "JwtSecret": "this is a sample jwt secret token required for quotify - it needs to have at least 256 bits (32 bytes long)",
+  "DomainName": "example.com",
   "ConnectionStrings": {
     "DefaultConnection": "Server=server-host;Database=db-name;Username=quotify-user;Password=user-secret"
   },