JWT Token Generation Process in .Net Core Web API

Simple JWT Token Generation

 

This is Controller Section of JWT Token Generation.

using System;
using System.Collections.Generic;
using System.IdentityModel.Tokens.Jwt;
using System.Linq;
using System.Security.Claims;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.IdentityModel.Tokens;
using Models;
using Repository.Interfaces;
using CentralSageFlickApi.Helper;
namespace CentralSageFlickApi.Controllers {
  public class AccountController: ControllerBase {
    private readonly IAccountService _accountService;
    private IConfiguration _config;
    public AccountController(IConfiguration config, IAccountService accountService) {
     _config = config;
     _accountService = accountService;
    }#
    region Token Generation
     [AllowAnonymous]
     [HttpPost]
     [Route("~/api/Token/TokenGenerate")]
    public IActionResult Login([FromBody] LoginModel login) {
     IActionResult response = Unauthorized();
     try {
      if (ModelState.IsValid) {
       var user = AuthenticateUser(login.Username, login.AppCode);
       if (user != null) {
        var passwordString = PasswordGeneration.DecryptString(user.PasswordSalt, user.Password);
        if (login.Password.Equals(passwordString)) {
         var tokenString = GenerateJwtToken(user);
         response = Ok(new {
          token = tokenString
         });
        } else {
         response = BadRequest(new {
          message = "Invalid Password!"
         });
        }
       } else {
        response = BadRequest(new {
         message = "Invalid User!"
        });
       }
      } else {
       response = BadRequest(new {
        message = String.Join(Environment.NewLine, ModelState.Values.SelectMany(v => v.Errors)
         .Select(v => v.ErrorMessage + " " + v.Exception))
       });
      }
     } catch (Exception ex) {
      response = BadRequest(new {
       message = ex.Message.ToString()
      });
     }
     return response;
    }
    private string GenerateJwtToken(UserRegisterModel userInfo) {
     var securityKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_config["Jwt:Key"]));
     var credentials = new SigningCredentials(securityKey, SecurityAlgorithms.HmacSha256);
     var claims = new [] {
      new Claim(ClaimTypes.Name, userInfo.Username),
       new Claim(ClaimTypes.Email, userInfo.Email),
       new Claim(ClaimTypes.NameIdentifier, userInfo.AppCode),
       new Claim(ClaimTypes.DateOfBirth, userInfo.AddedDate.ToString("yyyy-MM-dd")),
       new Claim(JwtRegisteredClaimNames.Jti, Guid.NewGuid().ToString())
     };
     var token = new JwtSecurityToken(issuer: _config["Jwt:Issuer"],
      audience: _config["Jwt:Audience"],
      claims: claims,
      expires: DateTime.Now.AddMinutes(Convert.ToInt32(_config["Jwt:Expire"])),
      signingCredentials: credentials);
     return new JwtSecurityTokenHandler().WriteToken(token);
    }
    private UserRegisterModel AuthenticateUser(string userName, string appCode) {
     UserRegisterModel user = _accountService.CheckUser(userName, appCode);
     return user;
    }#
    endregion
  }
}

Startup.cs

 

This is Startup.cs file.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Microsoft.IdentityModel.Tokens;
using Models;
using Repository.Interfaces;
using Repository.Services;
namespace CentralSageFlickApi
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }
        public IConfiguration Configuration { get; }
        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            #region Add CORS
            services.AddCors(options => options.AddPolicy("Cors", builder =>
            {
                builder
                .AllowAnyOrigin()
                .AllowAnyMethod()
                .AllowAnyHeader();
            }));
            #endregion
            #region JwtToken Authentication
            services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
              .AddJwtBearer(options =>
              {
                  options.TokenValidationParameters = new TokenValidationParameters
                  {
                      ValidateIssuer = true,
                      ValidateAudience = true,
                      ValidateLifetime = true,
                      ValidateIssuerSigningKey = true,
                      ValidIssuer = Configuration["Jwt:Issuer"],
                      ValidAudience = Configuration["Jwt:Audience"],
                      IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["Jwt:Key"]))
                  };
              });
            #endregion
            services.Configure<ReadConfig>(Configuration.GetSection("ConnectionString"));
            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
            services.AddTransient<IAccountService, AccountService>();
            services.AddTransient<ITheaterService, TheaterService>();
            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
        }
        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }
            app.UseAuthentication();
            app.UseCors("Cors");
            app.UseHttpsRedirection();
            app.UseStaticFiles();
            app.UseMvc();
        }
    }
}