services.AddAuthentication().
                 AddJwtBearer(options =>
                 {
                     options.TokenValidationParameters = new TokenValidationParameters
                     {
                         ValidateIssuer = true,
                         ValidateAudience = true,
                         ValidateLifetime = true,
                         RequireExpirationTime=true,
                         ValidateIssuerSigningKey = true,
                         ValidIssuer = configuration.GetSection("Jwt").GetSection("Issuer").Value,
                         ValidAudience = configuration.GetSection("Jwt").GetSection("Audience").Value,
                         IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(configuration.GetSection("Jwt").GetSection("SecretKey").Value)),
                         ClockSkew = TimeSpan.FromMinutes(0)
                     };
                 });

     [HttpGet]
        [Route("gettoken/{id}")]
        public IActionResult gettkn( string id)
        {
            var claims = new[]
            {
                new Claim(JwtRegisteredClaimNames.Jti,Guid.NewGuid().ToString("N")),
                new Claim("PersonId",id)
            };
            
            var credentials = new SigningCredentials(new SymmetricSecurityKey(Encoding.UTF8.GetBytes(configuration.GetSection("Jwt").GetSection("SecretKey").Value)),
                SecurityAlgorithms.HmacSha256);

            var token = new JwtSecurityToken
                (
                issuer: configuration.GetSection("Jwt").GetSection("Issuer").Value,
                audience: configuration.GetSection("Jwt").GetSection("Audience").Value,
                claims: claims,
                expires: DateTime.UtcNow.AddDays(1), 
                signingCredentials: credentials
                );

            return Ok(
               new
               {
                   token = new JwtSecurityTokenHandler().WriteToken(token)
               }
             );        
        }