I understand that this is a RuntimeException but for my usecase I need to catch it and set some attributes.
Context: I am using JPA EntityListeners for auditing and everything works fine when user accesses the application. The problem occurs when the application is accessed remotely using RemoteEJB. I am using a session object (Credentials which captures the user) in the EntityListener, so when the call is from RemoteEJB and because there is no session it fails as expected. This is the only exception I anticipate so I want to catch it and hardcode the auditing in this RemoteEJB accessing case. But somehow I am not able to catch it. I tried to catch javax.enterprise.context.ContextNotActiveException but to no avail.
public class CreateListener {
#Inject #Named("credentials") private Credentials credentials;
#PrePersist
public void setCreateAttributes(Auditable entity){
try {
entity.setCreateUserName(credentials.getUserName());
} catch (RuntimeException e) {
entity.setCreateUserName("RemoteEJB");
}
entity.setCreateTmstmp(new Date());
}
}
Environment: JDK 1.8, JBOSS EAP 7.1, hibernate-jpa-2.1-api, Hibernate 5.2.12.Final
Any help of alternative approach is appreciated.
TIA
-Avi
Related
When my application traffic gets high, StackExchange.Redis starts to throw RedisTimeoutException and after some minutes, my asp.net core application crashes.
The Windows event viewer says The process was terminated due to an unhandled exception. Exception Info: StackExchange.Redis.RedisTimeoutException.
Ok, I understand that there is some issue between my app and Redis, but while I can't solve this, how can I prevent the application to shutdown?
Inside startup.cs, I tried to put:
TaskScheduler.UnobservedTaskException += (object sender, UnobservedTaskExceptionEventArgs eventArgs) =>
{
eventArgs.SetObserved();
eventArgs.Exception.Handle(ex => true);
};
no success....
Any help ?
Tks
How are you creating the ConnectionMultiplexer instances?
Maybe you are not reusing a multiplexer instance and creating a lot of connections.
The ConnectionMultiplexer object should be shared and reused between callers. It is not recommended to create a ConnectionMultiplexer per operation. Check StackExchange.Redis documentation here for more information.
About the exception handling on Asp.NET Core, you can use the UseExceptionHandler diagnostic middleware to handle exceptions globally. Check this article for a complete explanation
Have you tried to put the block that throws the exception in a try/catch block? And perhaps make it try a few times with Polly when there is a timeout. https://github.com/App-vNext/Polly
Normally it shouldn't terminate your app, but since you didn't share any code, We can not be sure.
If you create a service class like below, you can encapsulate all of your redis calls, therefore catch the exceptions.
public class EmptyClass
{
private readonly ConnectionMultiplexer _connectionMultiplexer;
public EmptyClass(ConnectionMultiplexer connectionMultiplexer)
{
_connectionMultiplexer = connectionMultiplexer;
}
public void Execute(Action<ConnectionMultiplexer> action)
{
try
{
action.Invoke(_connectionMultiplexer);
}
catch(RedisTimeoutException ex)
{
}
}
public void TestRun()
{
Execute((ConnectionMultiplexer obj) =>
{
//do stuff with obj.
});
}
}
I agree with #thepirat000's answer, reason is ConnectionMultiplexer
You can use ConnectionMultiplexer according your Redis package (StackExchange.Redis or ServiceStack.Redis) and according your deployment environment
In my aspnet core application (like you) i have used StackExchange.Redis and i have deployed to windows server without any error within below Startup.cs settings
#region Redis settings ConnectionMultiplexer
services.AddDataProtection().ProtectKeysWithDpapi(protectToLocalMachine: true);
services.AddDataProtection()
.PersistKeysToFileSystem(new DirectoryInfo(#"c:\temp-keys"))
.ProtectKeysWithDpapiNG($"CERTIFICATE=HashId:{thumbPrint}", flags: Microsoft.AspNetCore.DataProtection.XmlEncryption.DpapiNGProtectionDescriptorFlags.None);
services.AddDataProtection().ProtectKeysWithDpapiNG();
services.Configure<StorageConfiguration>(new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory()).AddJsonFile("appsettings.json", optional: true, reloadOnChange: true).Build());
var redisConf = Configuration.GetSection("RedisConnection").Get<RedisConnection>();
ConnectionMultiplexer redis = ConnectionMultiplexer.Connect(redisConf.Host.ToString() + ":" + redisConf.Port.ToString());
services.AddDataProtection().PersistKeysToStackExchangeRedis(redis, "DataProtection-Keys");
services.AddSingleton<IConnectionMultiplexer>(ConnectionMultiplexer.Connect(redisConf.Host.ToString() + ":" + redisConf.Port.ToString()));
#endregion
Look here for basic usage https://stackexchange.github.io/StackExchange.Redis/Basics.html
I am sending an message through my standalone application that uses EJB MDB to communicate to my other application server that is running on JBOSS server.My application server is connected to a MSSQL server. In certain scenario, connection to the database is lost on application server side and we get following error -
Connection is reset.
Later , when i try to send message i don't get any error at my standalone EJB MDB logs and the process just stops executing.I get error log on application server side logs but same logs don't get propagated to my EJB MDB error logs.
As per my understanding, when db connection is lost all the ejb bean present in jboss container get nullified too.(I could be wrong here, i am new to EJB).
I tried implementing below code in my code that use to send message -
QueueConnection qcon = null;
#PostConstruct
public void initialize() {
System.out.println("In PostConstruct");
try {
qcon = qconFactory.createQueueConnection();
} catch (Exception e) {
e.printStackTrace();
}
}
#PreDestroy
public void releaseResources() {
System.out.println("In PreDestroy");
try {
if(qcon != null)
{
qcon.close();
}
if(qcon== null){
throw new Exception(" new exception occured.");
}
} catch (Exception e) {
e.printStackTrace();
}
}
I was in a impression that Queueconnection object will be nullified, when our db connection have been lost(as we are creating bean and making connection for message). But it doesn't seem to work.
I did found a way to call back my application after sending message. I used a separate temporary queue and used setJMSReplyTo method to set the reply destination. More info could be obtained from this
link. Hope this helps others.
I am developing a custom login module for jboss' jaas implementation. I would like to be able to access the HttpServletRequest object inside my login module. Does anyone know the best way to do this, if it's possible? I've been researching this, and so far I think I need to use a Callback of some kind, but I'm not sure.I found some WebSphere documentation that shows they have a WSServletRequestCallback that seems to be able to do this. Please suggest a simple example or documentation if jboss' jaas implementation have anything like this.
Update:
#kwart: As per your suggestion, I coded the following. Please suggest if this is the right way:
protected CallbackHandler _callbackHandler;
HttpServletRequest request = null;
ObjectCallback objectCallback = null;
Callback[] callbacks = new Callback[1];
callbacks[0] = objectCallback = new ObjectCallback("HttpServletRequest: ");
try
{
_callbackHandler.handle(callbacks);
}
catch (Exception e)
{
logger.logp(Level.SEVERE, CLASSNAME, METHOD_NAME, "Error handling callbacks", e);
}
try
{
if (objectCallback != null)
{
request = (HttpServletRequest) PolicyContext.getContext("javax.servlet.http.HttpServletRequest");
}
}
catch (PolicyContextException e) {
logger.logp(Level.SEVERE, CLASSNAME, METHOD_NAME, "Error getting request", e);
}
catch (Exception e)
{
logger.logp(Level.SEVERE, CLASSNAME, METHOD_NAME, "Exception occured augmenting JbossSubject", e);
}
You can use JACC PolicyContext to retrieve the HttpRequestObject in the LoginModule methods:
HttpServletRequest request = (HttpServletRequest) javax.security.jacc.PolicyContext
.getContext(HttpServletRequest.class.getName());
Update: Find sample usage in LoginModule here.
I got a solution from this site.
Used JSPI authentication. Configured an auth module in security domain in standalone as explained here .
Created a custom authenticator and a custom login module, configured the authenticator in jboss-web.xml and login module in security domain in standalone xml.
I jar'd them in a separate module and added that to jboss-deployment-structure.xml. Stored http request in ThreadLocal in the authenticator and retrieved it in my login module by simply reading the value stored in the Thread Local.
I have an MVC 4 web application. Using ELMAH, and Elmah.Contrib.WebApi, any exceptions that occur within my controllers, or API controllers (or their underlying services) are logged perfectly.
Where I run into trouble is with manually logging of errors. Specifically, inside my Global.asax, I have lots of initialization code (setting up automapper and the like). In order to catch problems which might happen in the initialization code, I have the following:
protected void Application_Start()
{
try
{
ControllerBuilder.Current.SetControllerFactory(new ErrorHandlingControllerFactory());
GlobalConfiguration.Configuration.IncludeErrorDetailPolicy = IncludeErrorDetailPolicy.Always;
GlobalConfiguration.Configuration.Filters.Add(new ElmahHandleErrorApiAttribute());
AutoMapperConfiguration.Configure();
AreaRegistration.RegisterAllAreas();
WebApiConfig.Register(GlobalConfiguration.Configuration);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
AuthConfig.RegisterAuth();
DatabaseConfig.Initialize();
SecurityConfig.Initialize();
}
catch (Exception e)
{
var context = HttpContext.Current;
var signal = ErrorSignal.FromContext(context);
if (signal != null)
{
signal.Raise(e, context);
}
}
}
Any exception caught inside the "catch" block will never be logged by ELMAH. Yet, I know that ELMAH is working because any other exceptions that will occur from this point on, inside any controller, will be logged. Therefore I have ruled out problems in the web.config, and the like.
Any suggestions? Thanks.
When the Applicaiton is executing the code in Application_Start it is still being initialized, and it is not handling any HttpRequest.
So the problem with your code is that HttpContext is null. In fact, the line ´ErrorSignal.FromContext(context);´ will throw an ArgumentNullException.
However, you can still use Elmah when there is no HttpContext (and it will basically log the error message and stack trace) as explained in this question.
So your catch would be:
catch (Exception e)
{
ErrorLog.GetDefault(null).Log(new Error(e));
}
Hope it helps!
I'm a newbie to Elmah but have had luck with something like this:
catch (Exception ex)
{
ErrorSignal.FromCurrentContext().Raise(ex);
return Json(string.Format("Failure: {0}", ex.Message), JsonRequestBehavior.AllowGet);
}
We're using EJB3 on GlassFish v2.
My application includes a GenericServlet called StartupServlet, which has an init method. java.util.TimerTask pollers started from this method cannot lookup facades from the InitialContext.
However if I make an HTTP request and do a lookup, it succeeds. Therefore I have a workaround now where my poller startup code makes an HTTP connection to a page which looks up the interfaces they need.
How can I rearrange my application so I don't need to use such a hack? If possible the solution needs to work on GFv3 as well.
Thanks in advance for your help!
On GF 2, I have a servlet that on start ensures that my timer is created. This looks up a remote session bean and calls it successfully from the init() (not actual code, distilled down to the important parts):
#EJB(name="TimerSessionRef", beanInterface=TimerSessionRemote.class)
public class StartTimers extends HttpServlet {
#Override
public void init() throws ServletException {
super.init();
try {
Context ctx = new InitialContext();
TimerSessionRemote timerSession = (TimerSessionRemote) ctx.lookup("java:comp/env/TimerSessionRef");
timerSession.createTimer();
} catch (NamingException ex) {
logger.blah();
}