Featured
JWT Authentication In ASP.NET 6
Last modified: May 22, 2022JWT is one of way to authenticate and authorize user against WEB APIs
1. Create a WEB API project
2. Remove old code
3. Install NuGet package
4. appsettings - setup JWT variables
"Jwt": {
"Key": "ertwet3245sgf2342werwergww4352345"
}
5. Get token method (in program.cs - above app.Run)
using Microsoft.AspNetCore.Authorization;
using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
var app = builder.Build();
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
app.UseSwagger();
app.UseSwaggerUI();
}
app.UseHttpsRedirection();
app.MapPost("/auth/getToken", [AllowAnonymous] (UserDto user) =>
{
/*check if username and password are correct
if correct generate JWT token*/
if(user.UserName == "[email protected]" && user.Password == "admin") //you need to check aganist database or identity server
{
var securityKey = Encoding.UTF8.GetBytes(builder.Configuration["Jwt:Key"]);
var handler = new JwtSecurityTokenHandler();
var descriptor = new SecurityTokenDescriptor
{
Subject = new ClaimsIdentity(new[] {
new Claim(JwtRegisteredClaimNames.Name, user.UserName)
}),
Expires = DateTime.UtcNow.AddMinutes(30),
SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(securityKey), SecurityAlgorithms.HmacSha256Signature)
};
var token = handler.CreateToken(descriptor);
var jwtToken = handler.WriteToken(token);
return Results.Ok(jwtToken);
}
else
{
return Results.Unauthorized();
}
});
app.Run();
record UserDto(string UserName, string Password);
5. Test application
Successful
Fail
