我有一个使用 .net core 2.0 构建的 Web Api 和一个使用 xamarin 构建的移动应用程序。要登录移动应用程序，请通过传递（用户名和密码）调用 web api。如果凭证是有效的 Web Api，则返回一个 JWT 令牌。该移动应用程序具有一项功能，即使您关闭应用程序（例如（facebook、Instagram 等）），用户也可以保持登录状态。
问题是：
【问题讨论】：
标签： c# .net-core jwt .net-core-2.0 jwt-auth
// This code tested with dotnet core 2.1 ( WebApi + Jwt ) with sample structure
//为你的项目添加一个类Auth
public static class Auth
{
private static string salt = "jnyanendra_sethi"; // u can chose any key satisfying the length
private static int timeoutInMinute = 1;
private static string _issuer = "http://localhost:5000";
private static string _audience = "http://localhost:5000";
//Generate Token
public static string GenerateToken(Customer customer, List<SupplierInfo> lstSpplierInfo)
{
var securitykey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(salt));
var credential = new SigningCredentials(securitykey, SecurityAlgorithms.HmacSha256);
// var suppliers = any json string e.g. [{"SupplierId":1001,"SupplierName":"RateHawk"},{"SupplierId":1002,"SupplierName":"Hotelbeds"}]
var suppliers = JsonConvert.SerializeObject(lstSpplierInfo);//"ur json object to store in claim";
var claims = new List<Claim> {
new Claim("CustomerName", customer.CustomerName),
new Claim("Suppliers",suppliers )
};
var mytoken = new JwtSecurityToken(issuer: _issuer, audience: _audience,
claims: claims, notBefore: DateTime.Now, expires: DateTime.Now.AddMinutes(timeoutInMinute), signingCredentials: credential);
var tokenValue = new JwtSecurityTokenHandler().WriteToken(mytoken);
return tokenValue;
}
//Validate token
public static void ValidateJwtToken(this IServiceCollection services)
{
var securitykey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(salt));
var credential = new SigningCredentials(securitykey, SecurityAlgorithms.HmacSha256);
var tokenParam = new TokenValidationParameters
{
ValidateIssuerSigningKey = true,
ValidIssuer = _issuer,
ValidAudience = _audience,
ValidateIssuer = true,
ValidateAudience = true,
RequireSignedTokens = true,
IssuerSigningKey = credential.Key,
ClockSkew = TimeSpan.FromMinutes(timeoutInMinute)
};
services.AddAuthentication(
options =>
{
options.DefaultScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(
options =>
{
options.TokenValidationParameters = tokenParam;
});
}
}
[Route("api/[controller]")]
[ApiController]
public class HotelController : ControllerBase
{
[HttpGet("Search")]
public SearchReponse Search()// u can take search parameters for input
{
// based on apikey or username, call db for first time
// get customername / supplierinfo from db
Customer customer = new Customer() { CustomerId = "CUS001", CustomerName = "TestCust" };// dummy
if (customer == null)
{
this.HttpContext.Response.StatusCode = 401;
return new SearchReponse()
{
ErrorInfo = new ErrorInfo()
{
Code = "0",
Description = "No Customer Found"
}
};
}
string token = Auth.GenerateToken(customer, GetDummyDataToStoreInClaim());
SearchReponse reponse = new SearchReponse()
{
GeneralInfo = new GeneralInfo()
{
Token = token,
Duration = 0
},
Hotels = "Hotels Data",
};
return reponse;
}
[Authorize]
[HttpGet("Get/{id}")]
public ActionResult<string> Get(int id)
{//// Getting the data stored in claim that required for further process
var CustomerName = HttpContext.User.Identities.FirstOrDefault().Claims.FirstOrDefault(x => x.Type == "CustomerName").Value;
var strSuppliers = HttpContext.User.Identities.FirstOrDefault().Claims.FirstOrDefault(x => x.Type == "Suppliers").Value;
return CustomerName;
}
}
我用过的型号：
public class SearchReponse
{
public GeneralInfo GeneralInfo { get; set; }
public ErrorInfo ErrorInfo { get; set; }
public string Hotels { get; set; }
}
public class GeneralInfo
{
public string Token { get; set; }
public long Duration { get; set; }
}
public class ErrorInfo
{
public string Code { get; set; }
public string Description { get; set; }
}
在 Startup.cs 中
public void ConfigureServices(IServiceCollection services)
{
services.ValidateJwtToken();
services.AddAuthorization(Options => {
Options.DefaultPolicy = new AuthorizationPolicyBuilder(JwtBearerDefaults.AuthenticationScheme).RequireAuthenticatedUser().Build();
});
services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
}
--
【讨论】：
如何在用户登录应用程序之前保持 JWT 令牌有效 无需再次询问他/她的登录凭据即可给他/她 另一个有效的 JWT 令牌？
您可以设置令牌到期日期并对其进行跟踪。
用户决定退出应用后，如何让 JWT 令牌失效？
更新：
JWT 由 Header、Payload 和 Signature 组成。您可以阅读有关它的所有内容here 在有效负载中，您可以设置一个名为：“exp”的声明。
The docs: “exp”（过期时间）声明标识过期时间 或者在此之后，JWT 不得被接受处理。这 处理“exp”声明需要当前日期/时间 必须早于“exp”声明中列出的到期日期/时间。
另外，在研究澄清我的答案时，我发现了这个 SO 答案：JSON Web Token expiration。
【讨论】：