How do i avoid ObjectDisposedException when i access the db with EF Core via API Requests for JWT Auth? - asp.net-core

Question

I am working on a API right now where i can send /api/login get a jwt token and use it further to do some stuff on that api with my client app later
thats my startup where i add the services :
services.AddScoped<IUserCoreController>(x => new UserCoreController(x.GetRequiredServic<TerraContext>(), x.GetRequiredService<IHashEngine>()));
services.AddScoped<ITokenFactory>(x => new TokenFactory(x.GetRequiredService<IConfiguration>(), x.GetService<JwtSettings>(), x.GetService<AppDataSettings>(),x.GetRequiredService<IUserCoreController>()));
With this method i try to access to my db _context and check if a user with that email exists and return true/false
public async Task<ResponseModel> Authenticate(string email, string password)
{
using (var db = _context)
{
//logic of my method
}
the code below shows the constructor for this class and how i inject the dbcontext and a hashengine
public class UserCoreController : IUserCoreController
{
TerraContext _context;
IHashEngine _hashEngine;
public UserCoreController(TerraContext context, IHashEngine engine)
{
_hashEngine = engine;
_context = context;
}
until now i get a true from this method after that i generate a jwt token with the class below
{
public class TokenFactory : ITokenFactory
{
IUserCoreController _userCore;
TerraContext _context;
IConfiguration _config;
JwtSettings _jwtSettings;
AppDataSettings _appDataSettings;
public TokenFactory(IConfiguration config, JwtSettings jwtsettings, AppDataSettings appDataSettings, IUserCoreController userCore)
{
_config = config;
_jwtSettings = jwtsettings;
_appDataSettings = appDataSettings;
_userCore = userCore;
}
public async Task<ResponseModel> Authenticate(LoginModel model)
{
var response = await _userCore.Authenticate(model.Email, model.Password);
return response;
}
public async Task<TokenResponse> GenerateJwtToken(string id)
{
var token = new TokenResponse();
var user = await _userCore.GetUser(id);
var securityKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_jwtSettings.SecretKey));
var credentials = new SigningCredentials(securityKey, SecurityAlgorithms.HmacSha256);
var claims = new List<Claim>();
if (!String.IsNullOrEmpty(user.Firstname))
claims.Add(new Claim("firstname", user.Firstname));
if (!String.IsNullOrEmpty(user.Lastname))
claims.Add(new Claim("lastname", user.Lastname));
if (!String.IsNullOrEmpty(user.Username))
claims.Add(new Claim("userId", user.UserId));
if (!String.IsNullOrEmpty(user.Username))
claims.Add(new Claim("appId", _appDataSettings.ApplicationId));
if (!String.IsNullOrEmpty(user.Username))
claims.Add(new Claim("orgId", _appDataSettings.OrganisationId));
var jwt = new JwtSecurityToken(
issuer: _jwtSettings.Issuer,
audience: _jwtSettings.Audience,
expires: DateTime.Now.AddHours(3),
signingCredentials: credentials,
claims: claims
);
var tokstring = new JwtSecurityTokenHandler().WriteToken(jwt);
token.Token = tokstring;
token.Email = user.Email;
token.TokenId = Guid.NewGuid().ToString();
return token;
}
public async Task<bool> ValidateToken(string token)
{
await Task.Delay(100);
var tokenHandler = new JwtSecurityTokenHandler();
var validationParameters = GetValidationParameters();
SecurityToken validatedToken;
IPrincipal principal = tokenHandler.ValidateToken(token, validationParameters, out validatedToken);
return true;
}
public async Task<ClaimsPrincipal> GetUser(string token)
{
await Task.Delay(100);
var tokenHandler = new JwtSecurityTokenHandler();
var validationParameters = GetValidationParameters();
SecurityToken validatedToken;
var principal = tokenHandler.ValidateToken(token, validationParameters, out validatedToken);
return principal;
}
private TokenValidationParameters GetValidationParameters()
{
return new TokenValidationParameters()
{
ValidateIssuer = true,
ValidateAudience = true,
ValidateIssuerSigningKey = true,
ValidAudience = _jwtSettings.Audience,
ValidIssuer = _jwtSettings.Issuer,
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_jwtSettings.SecretKey)),
ClockSkew = TimeSpan.Zero
};
}
}
I get the Exception System.ObjectDisposedException: Cannot access a disposed context instance. A common cause of this error is disposing a context instance that was resolved from dependency injection and then later trying to use the same context instance elsewhere in your application. This may occur if you are calling 'Dispose' on the context instance, or wrapping it in a using statement. If you are using dependency injection, you should let the dependency injection container take care of disposing context instances.
Should i just stop coding with a using() statement with my DbContext?