WebApp-WebAPI-OpenIDConnect-DotNet not deploying on azure - asp.net-mvc

Question

I have created sample project of WebApp-WebAPI-OpenIDConnect-DotNet. Reference project is available on git.
I followed all the steps as described on git repo. My sample project is working properly on local host. But when I am deploying my project on Azure it's giving following error.
Please check below stack trace.
Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
CMS.Web.Utils.NaiveSessionCache.Load() in c:\a\src\CMS.Web\CMS.Web\Utils\NaiveSessionCache.cs:30
CMS.Web.Utils.NaiveSessionCache..ctor(String userId) in c:\a\src\CMS.Web\CMS.Web\Utils\NaiveSessionCache.cs:23
CMS.Web.Startup.<ConfigureAuth>b__2(AuthorizationCodeReceivedNotification context) in c:\a\src\CMS.Web\CMS.Web\App_Start\Startup.Auth.cs:83
Microsoft.Owin.Security.OpenIdConnect.<AuthenticateCoreAsync>d__1a.MoveNext() +4995
System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() +22
Microsoft.Owin.Security.OpenIdConnect.<AuthenticateCoreAsync>d__1a.MoveNext() +6529
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
Microsoft.Owin.Security.Infrastructure.<BaseInitializeAsync>d__0.MoveNext() +595
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
Microsoft.Owin.Security.Infrastructure.<Invoke>d__0.MoveNext() +264
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.<RunApp>d__5.MoveNext() +191
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
Microsoft.Owin.Security.Infrastructure.<Invoke>d__0.MoveNext() +665
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.<RunApp>d__5.MoveNext() +191
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.<DoFinalWork>d__2.MoveNext() +189
Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.StageAsyncResult.End(IAsyncResult ar) +69
Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.IntegratedPipelineContext.EndFinalWork(IAsyncResult ar) +64
System.Web.AsyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +415
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Answer 1

I'm on an identical case. My project is working on development environment and getting NullRefenceException on same line after publishing it to production evironment. After working on it, I've discovered that Request.Current was OK, but Request.Current.Session was null. So, I´ve changed my code to be like that:
public void Load()
{
lock (FileLock)
{
if (HttpContext.Current != null && HttpContext.Current.Session != null)
{
if (HttpContext.Current.Session[CacheId] == null)
throw new System.NullReferenceException("CacheId is null");
Deserialize((byte[]) HttpContext.Current.Session[CacheId]);
}
}
}
After that it´s giving me WebExcetpion 400 (BAD REQUEST), and that´s happening before session is created.
To Handle this kind of error, I changed the Startup.Auth.cs:
Notifications = new OpenIdConnectAuthenticationNotifications()
{
AuthenticationFailed = OnAuthenticationFailed,
...
}
and then:
private Task OnAuthenticationFailed(AuthenticationFailedNotification<OpenIdConnectMessage, OpenIdConnectAuthenticationOptions> notification)
{
UtilLogger.PublishException(notification.Exception);
notification.HandleResponse();
notification.Response.Redirect($"{postLogoutRedirectUri}?message={notification.Exception.Message}");
return Task.FromResult(0);
}

Answer 2

I see a similar issue, HttpContext.Current is null initially when getting the token and when it tries to save that token to the cache, you see this error in the Load/Persist methods. Not sure if this is expected, but adding a not null check on the HttpContext.Current in the Load and Persist methods would mitigate the object null reference exception.