ASP.NET Authorize Filter Denies Access for User in Specified Role - asp.net-core

Question

In my ASP.NET Core 2.0 Application, I am stuck with an issue an Admin logged in User cannot access controller I used the Authorize Filter on [Authorize(Policy="AdminAlone")].
I confirmed that the user is in the "Administrators" role and added the policy in startup.cs but it redirects to an AccessDenied view when I try to access the controller.
I saw a similar problem on this link, but the solution didn't help me
Startup Class in MVC Client - ConfigureServices
services.AddMvc();
services.AddSession();
JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
services.AddAuthorization(options =>
{
options.AddPolicy("AdminAlone", policy => policy.RequireRole("Administrators"));
});
services.AddAuthentication(options =>
{
options.DefaultScheme = "Cookies";
options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
options.DefaultForbidScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddCookie("Cookies")
.AddOpenIdConnect("Bearer", options =>
{
options.SignInScheme = "Cookies";
options.Authority = "http://localhost:5000";
options.RequireHttpsMetadata = false;
options.ClientId = "mvcWeb";
options.ClientSecret = "spring12345";
options.ResponseType = OidcConstants.ResponseTypes.CodeIdToken;
options.SaveTokens = true;
options.GetClaimsFromUserInfoEndpoint = true;
options.Scope.Add("NuB.HospitalSearch");
options.Scope.Add("offline_access");
});
Web API ConfigureServices
var jwtSecurityTokenHandler = new JwtSecurityTokenHandler
{
InboundClaimTypeMap = new Dictionary<string, string>()
};
services
.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
.AddJwtBearer(option =>
{
option.Audience = "NuB.HospitalSearch";
option.Authority = "http://localhost:5000";
option.RequireHttpsMetadata = false;
option.SecurityTokenValidators.Clear();
option.SecurityTokenValidators.Add(jwtSecurityTokenHandler);
option.TokenValidationParameters = new Microsoft.IdentityModel.Tokens.TokenValidationParameters
{
ValidateAudience = true,
ValidAudience = "NuB.HospitalSearch",
ValidateIssuer = true
};
});

Answer 1

You may try the following. Inside your AddOpenIdConnect configuration add
options.TokenValidationParameters = new TokenValidationParameters {
NameClaimType = JwtClaimTypes.Name,
RoleClaimType = JwtClaimTypes.Role
};
In fact, this property defines the types and definitions required for validating a token. Please refer to this post from Dominick Baier for a more detailed explanation.