I am suddenly getting the error: "Unable to locate persister for the entity named 'MyLib.Project'."
I did not make any code changes to this project since the last time I published it. The reason I went into the code to look at it is because a user reported that the web page that utilizes this library was giving an error. I have also checked the eager loading of the provider as per (NHibernate - Random occurrences of "Unable to locate persister") but I am already eagerly loading.
Furthermore, I even changed my data provider configuration to:
.Mappings(Function(x) x.FluentMappings.AddFromAssemblyOf(Of Project)())
I stepped through the code and actually saw it find the Project mapping and step through it. There are no exceptions thrown while building the provider, but yet the web app still fails when I try to fetch a Project from the DB.
Update
I have tested this same exact code with a desktop application and it works perfectly fine. It seems to me the problem must be with NHibernate and the Web Application. Does anyone have any ideas about this specifically?
The answer to this, of course, is that I made a mistake.
I had two session factories in use in the same program and I passed a session from the wrong factory to one of my functions. So the error is correct, because the session it was passed was unaware of the Project type. I found this out eventually by looking at the Connection property of the session I was querying through.
Hopefully this helps someone else who may have made the same mistake.
Related
Our application is using CefSharp version 73.1.130. The issue only occurs on a small number of internal workstations within our organization. Worth noting, we are also seeing the same error with CefSharp version 92. Another strange thing is that it the issue is consistent, but only when the web apps are launched through certain navigations. Other navigations work consistently for these users.
We use RegisterJsObject to register a javascript object with browser. If I understand correctly, asynchronous binding is preferred moving forward.
The issue presents as strange/unexpected behavior in the hosted web application due to failure to retrieve context from the host WinForms application. The behavior would suggest a failure to register/bind the js object with the RegisterJsObject method. However, that method is not throwing an exception.
Enabled Cef logging showed the following error:
ERROR:JavascriptRootObjectWrapper.cpp(34)] IBrowserProcess is null, unable to bind object
After looking into the code, it appears the location that the value pointed to by "IBrowserProcess" is set is in WcfEnabledSubProcess::OnBrowserCreated (https://github.com/cefsharp/CefSharp/blob/cefsharp/73/CefSharp.BrowserSubprocess.Core/WcfEnabledSubProcess.cpp). I was able to build CefSharp and add additional logging to that method.
On my workstation (I'm not affected by the issue), I get through OnBrowserCreated with no exceptions. However, on my coworkers workstation I see the following line is failing:
...
channelFactory->Open();
auto browserProcess = channelFactory->CreateChannel();
auto clientChannel = ((IClientChannel^)browserProcess);
try
{
clientChannel->Open(); <-- FAILS
browser->ChannelFactory = channelFactory;
browser->BrowserProcess = browserProcess;
}
catch (Exception^)
{
}
}
With the error:
There was an error reading from the pipe: The pipe has been ended. (109, 0x6d)
Has anyone seen this issue before? I'm not sure how much this will help, but does anyone know if it's possible to enable WCF tracing with the CefSharp.BrowserSubProcess.exe. I have been trying this, but no luck so far.
My main program is an ASP.Net Core Web API that has a third party library in a hosted service. The third party library is initializing fine but then it throws some errors sometime throughout its lifecycle.
It supplies a way of hooking into the object via an event and will let me know what the error is so that I can handle it but it still throws in the third party library..
Since I am handling the event myself, I want to completely ignore these errors that are occurring in this library. Is there anyway that I can do that?
I have already tried to add a global exception handler and the strange thing is, this exception handler never gets hit. The only way I can get the exception is to set my exception settings to break when CLR exceptions happen like in the picture above
This does not crash my program. For some reason, the program just hangs. When I turn off CLR exceptions in the "Break when thrown" window, then the program runs just fine. It is almost like visual studio is doing something special to handle these types of exceptions that a console version cannot do
The only way that I can seem to get a console version of this running, is attach a visual studio debugger to the process and when the exception is hit, press the green play button "Continue" in visual studio. Otherwise the application just seems to hang on the exception being thrown by the third party library.
The application will run fine as long as visual studio is attached and the CLR break exceptions are not checked
Does anyone know how to make sure that these types of exceptions do not hang the program when released?
Additional Info:
The third party library is a .NET Framework 4 library
The Asp.Net project is targetting "net5.0-windows"
The 3rd party class is probably using multi-threading
if it helps, this is how I am creating the third party class
Handling NullReferenceException in release code（Official advice）
It's usually better to avoid a NullReferenceException than to handle it after it occurs. Handling an exception can make your code harder to maintain and understand, and can sometimes introduce other bugs. A NullReferenceException is often a non-recoverable error. In these cases, letting the exception stop the app might be the best alternative.
However, there are many situations where handling the error can be useful:
1.Your app can ignore objects that are null. For example, if your app retrieves and processes records in a database, you might be able to ignore some number of bad records that result in null objects. Recording the bad data in a log file or in the application UI might be all you have to do.
2.You can recover from the exception. For example, a call to a web service that returns a reference type might return null if the connection is lost or the connection times out. You can attempt to reestablish the connection and try the call again.
3.You can restore the state of your app to a valid state. For example, you might be performing a multi-step task that requires you to save information to a data store before you call a method that throws a NullReferenceException. If the uninitialized object would corrupt the data record, you can remove the previous data before you close the app.
4.You want to report the exception. For example, if the error was caused by a mistake from the user of your app, you can generate a message to help them supply the correct information. You can also log information about the error to help you fix the problem. Some frameworks, like ASP.NET, have a high-level exception handler that captures all errors to that the app never crashes; in that case, logging the exception might be the only way you can know that it occurs.
So after days of research I've finally found an event to hook into to give you error messages from ANY source no matter how many level deep you go in threads.
AppDomain.CurrentDomain.FirstChanceException += CurrentDomain_FirstChanceException;
Hooking into this event it will allow you to see errors from every library and every thread. Simply place the above into you program.cs (or whatever startup file you have) and magically you will be flooded with all of the unknown errors from all of the 3rd party libraries you thought were once flawless.
private static void CurrentDomain_FirstChanceException(object sender, System.Runtime.ExceptionServices.FirstChanceExceptionEventArgs e)
{
Console.WriteLine(e.Exception.Message, e.Exception.StackTrace);
}
I've done so with the following method and low and behold. The third party library was trying to reference another project in an unsafe way and throwing an error. Since I didn't need this other project reference the built exe did not have a reference to this assembly because I had no direct reference to it in the project (darn smarty pants who need to optimize everything). I was able to run correctly because in my visual studio solution, I had a reference to this other project. So the third party library would pick up on it as soon as visual studio connected with the debugger through some sort of dark magic.
Anyways, I made a throw away object that used the project that was required and the issue was solved.
I really hope that this helps someone else and saves them the days it took me to find this.
I have a site built using MVC4 which is getting content out of a database and it all works fine.
If I then rebuild the solution and try to refresh the page to check my changes, I will always get the SQL Network Interfaces, error: 26 saying that I cannot connect to the server.
However, if I then browse to my homepage and then back to the page I was looking at it will work fine.
Does anyone know what could cause this problem as it is really annoying
EDIT
Further to this I have found it is when the AuthorizationContext filterContext is being loaded after the rebuild that it cannot connect to the db
EDIT 2
As with neil below I have found that I only get the problem if I try to access a page that has had a role assigned to it
I'm seeing the exact same problem and can trace it to the .ASPXAUTH session cookie in the browser. Delete that cookie and the database error goes away until the next rebuild.
The error occurs regularly if you are authenticated and then rebuild the project and try to browse any page that either:
Requires authentication
Makes a call to the User object (e.g. #if (User.IsInRole("Administrators")))
If you have the AuthorizeAttribute filter set in App_Start/FilterConfig.cs you'll get this on every page.
This seems to be new behavior following the most recent Patch Tuesday updates. Previously, I was seeing weird behavior where I would remain logged in but I would loose my roll membership. After the most recent patches, it seems Simple Membership chokes when it gets a bad .ASPXAUTH cookie (invalid because of the rebuild).
I've got the correct connection string in InitializeSimpleMembershipAttribute.cs but it's like Simple Membership is defaulting to something else in this one instance.
Note that I've moved the Simple Membership databases from the original (localDb) to a full-fledged (local) SQL Server instance. Don't know why that would matter, and it works fine in all other cases.
Update:
I've also tried making the connection string name the same as the EF context name (e.g. "ProjectContext") on the theory that it is defaulting to the standard convention, but that made no difference. I am explicitly identifying the connection string name in all my context class constructors (using the : base("connectionString") syntax) and Simple Membership is able to find the right connection string all other times.
Update 2:
The problem only occurs after rebuild when accessing a page protected by role. A simple [Authorize] won't trigger it. You need something like [Authorize(Role="Admin")]. I've replicated this on a new MVC 4 project with no other modifications, using the default (localDb) database. Clear the cookie and that same user can access the protected content w/o any problems. I believe this is a core .NET or MVC bug and needs to be reported as such.
This happened to me while rebuilding the application when I was logged in the browser.
Deleting cookies fixed the problem for me.
When using SimpleMembership, this bug occurs with any use of Roles-not just in the controller, but also when I use:
if(Roles.IsUserInRole(rolename){...
I am late to the game with this answer, but I added [InitializeSimpleMembership] to my home controller and I think that fixed it.
I have a problem with WCF. My testing code is pretty simple.
I call a service layer method on my server from my silverlight application and print the result in a textbox.
Everything of this is surrounded by try-catch.
When my service layer method simply returns a constantly defined string there seems to be no problems - however as soon as it calls a more complex method it fails.
While debugging it does not even reach the complex model method; it fails before that inside some auto-generated code from microsoft:
/WuSIQ.jpg
As the error message "NotFound" is not exactly the most helpful or specific you can imagine my trouble googling for hints.
I thought maybe the auto-generated code could only send simple data so I made a temporary string and returned that, but this did not help.
I have already: a client access policy, a service reference added, removed duplicate reference in ServiceReferences.ClientConfig and a ServiceLayer.svc.cs.
I am debugging by running from the main window and my breakpoints are picked up.
Anyone?
I had some errors in the server side method that were quickly found after debugging was fixed.
I fixed this, as I said in comments, setting the project to have "Multiple Startup Projects".
Whenever I had troubles with updating the WCF service methods one of these usually solved it all:
1 Delete all bin and obj folders (specifically selecting re-build might do the same).
2 The servicelayer will not succesfully auto-update (but will work!) unless this:
[ServiceContract(Namespace = "")]
... is set to this:
[ServiceContract(Namespace = "YourServiceLayerName")]
3 Right clicking on the servicereference and selecting "update...".
Sometimes it would stop debugging again, but a forced full re-build would return it to normal.
I hope this helps someone.
I'm fairly new to CakePHPand am building a site using the Auth component. A couple of times I have tried to do things with this component which have caused the error
Fatal error: Call to undefined method stdClass::user() in /ftphome/site/app/controllers/users_controller.php on line 395
The line it refers to in this case is
$this->User->read(null, $this->Auth->user('id'));
This error does not disappear when I revert the code back to how it was before the error and I only seem to be able to get rid of it by removing some files on the server (I'm not sure which files, when I tried removing all files in the tmp directory the error persisted so I removed the entire site and restored from the latest svn revesion.
In this particular case I think I caused the error by putting the following code in app_controller
class AppController extends Controller {
function beforeRender() {
$this->set('test', $this->Auth->user());
}
}
Which I copied from this thread http://groups.google.com/group/cake-php/browse_thread/thread/ee9456de93d2eece/cff6fe580d13622b?lnk=gst&q=auth
A previous time I caused the issue by attempting to update the Auth user details after updating the user in the database.
I can see I'm somehow removing the user object from the Auth object but I can't understand why I need to delete files in the site to get it back or how the code above removes it - any help would be much appreciated.
Edit
It looks like in the case I mentioned above, the problem was the app_controller.php file which I'd copied into my app/controllers directory. Just having the file with an empty class declaration causes this error - can anyone provide further insight?
Further edit
I've realised I've been a bit silly and the problem was caused by me putting app_controller.php in /app/controllers/app_controller.php when there was already one in /app/app_controller.php - thanks for the input though Andy, it helps me understand a bit more what was happening.
This error is normally thrown when a class instance (in your case an instance of Auth) has been serialised to disk, then re-read/deserialised in another request but the class definition (i.e. Auth) has not been loaded yet, so PHP creates it as an "stdClass" (standard class.)
When you remove your site files, you're removing the session storage (IIRC it's the Cache folder in a CakePHP app) so at the next request, a new session is created from scratch.
It's been a while since I last used CakePHP (I switched to Zend) so I cannot remember if Cake includes files it requires using an __autoload function or not.
On that mailing list post, someone says that you can this $this->Auth->user() in a view, but in the controller, you can use $session->read('Auth.User') to get the user component. Not sure what the difference is, maybe $this->Auth is a view helper, so isn't available in the controller?