My web app is integrated with App Insights for telemetry purposes.
My question is this:
If I have my app insights configured incorrectly, i will get an error.
Should this error break the UI, or gracefully let the user know of the error, or should it just be silent/ignore it?
thanks.
It will depend on the type of application, end users etc.
Type of application - If this is going to be a public facing application, I don't think you would want the end users to know that there was an error with instrumentation. A regular check of the data being collected could help you understand if AppInsights is not configured correctly.
End users - If the end users are internal to your organization/team, the error information on UI could be considered for faster diagnosis.
Depending on the Framework/platform being used for the application, you could enable it using Auto-Instrumentaion which does not require a lot of configuration update to enable AppInsights. The chance of error here would be minimal.
However, if you are going with the SDK method, you could check the AppInsights logs, dashboards after a few minutes of hosting the application, to ensure that the data is flowing in.
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.
How do I handle and return a human readable error in a Java Azure Function app?
All examples of this on a Google search, are just simple instructions on how to do a try-catch, which is not my question.
More specfically, how do we design the return status code and the response body of the request, in a way that provides the most flexibility to a wide array of situations?
Given that we are not integrating Spring-Boot in this case, and that we do not have access to anything Spring.
Given that my API generally returns an object that we will call Pojo1, on error, what is the best way to return a informative message.
NOTE: Of course, I do know there are situations where you want security through obscurity, in which case I would probably choose logging errors to app insights. This is not my question though.
Well, you can set custom headers while returning the request. This
can be done using a setHeader function.
You can also use azure service bus or event grid which will carry
specific messages regarding the errors.
Also, you can use azure monitoring which collect all the error and
notify you when everything happens.
Refer this article by Eugen Paraschiv for indepth explanation on how to use setheader.
Refer this documentation on azure service bus and this documentation on event grid.
Refer this documentation on azure monitoring logs.
Is there a way to test if current user has been authenticated to BBG? I have my c# program which uses BBG API, and want to check if the user logged in the service before, either via API calls or the BBG Terminal. This check can then be used to distinguish whether the user's network is unavailable or simply he hasn't logged in yet.
Thanks!
There's a couple of ways to interpret your question, so I'll answer both... (I'm speaking from the perspective of using the Java API, but it should be pretty similar on C#.)
1. Can I tell whether the user connect to Bloomberg (i.e. are there network issues / are they are logged in)?
Yes - you can create a new Session, try to start it using .start(). If it fails or returns false, you cannot connect. If it starts, you can call .openService("//blp/apiauth"). Again, if it fails or returns false, you cannot connect.
If you cannot connect, you may or may not be able to determine why you cannot... Nevertheless, I would suggest registering a callback to the BLP API logging framework. In our code, we we-direct these to the logging framework we use throughout our code.
2. The user has created a Session (pre-cursor to a Service) - can I tell if the Session has been started?
Unfortunately - no. There is nothing in the API to allow you to determine the state of the Session. (I suppose you could try starting it, and if it starts it wasn't started, and if it fails, it was started - but that strikes me as an unhelpful or risk appraoch.)
I am trying to create a testing application to validate server side error messages. Right now our framework is such that each time a incorrect value is entered in a field and the submit button is clicked and on submission, the error message displayed on the page is captured.
Is there anyway I can bypass this technique, such that the validation happens only in the server side and is passed back to the client side, without having to reload the page each time.
Any other ideas would be much appreciated. Please try to ignore the lameness of the question :( I'm just starting off and wanted to try something new to reduce the time taken to capture the error messages.
Thanks a lot..!!
Use AJAX, Luke!
There are a lot of options to do this. You may use jQuery.ajax for sending your form data to some validation servlet. Or you may use JSF for it. It largely depends on your framework and/or architecture of your application.
Generally, in software design, which of the options below is preferred when there is a problem or error with a resource such as a database or file?
Show an error message
Do not show an error message and act as though the resource was empty (eg. do not populate a GUI component)]
For example, should the user see an empty DataGrid following which they complain, or should there be an error message? Which is better?
I don't see this as an either/or. Also, we need to consider all "users" of the system.
First consider the UI. Let's consider a contrived general case: you are populating a UI by calling a service which in turn uses a couple of of databases (for example a "current data" and an "historic data") database.
There are at least these possibilities:
It all works, data is retrieved
It all works but as it happens there's no data for this particular query
Can't reach the service
Service is invoked, but one database is down
Service is invoked, but both databases are down
Then also consider your application's semantics. Can your applciation procede in a "degraded" mode if all the data cannot be retrieved? For example, we can't query the history but that doesn't stop us creating a new item.,
Now also consider the roles here. There's the person using the UI, there's also support and maintenance people who need to know about and fix problems.
My general rules:
First Failure Data capture: Whichever component first detects an error should log it in some detail. So, service up, database down the service should log the problem. Service down, the UI should log the problem. This log should be a technical record targeting the support roles.
UIs should be tolerant: if at all possible run in a degraded mode. So if the service is down but (for example) local working is possible put up an empty screen and continue. BUT ...
Always indicate a problem: The "no data for this query" and "databases unavailable" cases may both result in an empty screen. The user needs to know the status of the display, is it showing complete information, partial information (eg. because one DB is down) or is no information available (eg. service or both dbs down). So have a "Status" field somewhere on the screen. Giving messages such as
Historica Data not currently available
or
There are problems retrieveing
information, if these persist please
contact support ...
There are some pitfalls to each of the options
Showing error message
This is specially helpful when your application is in testing stage or public testing. Also when clients meets an error, he or she can copy down the details and forward to you.
However sometimes this error message gets very ugly (call stacks and so on - remember ASP.NET?) and it becomes so large that it becomes difficult for clients to copy down the details.
Do not show error message and act as though nothing happened =)
This is useful when you don't want error messages to cog up your software UI design. But be reminded that it becomes difficult and further error prone when clients can't differentiate between an actual error, or really nothing on the GUI. The error stays there and nothing gets fixed.
My stand
Get the best of both worlds. In fact most modern applications how have a very good error handling process. I'll take the example of Mozilla Firefox 3.
A deadly error occurred and Firefox crashes
Error is captured and stored into a file as a form of error report
Error Reporting Application pops up apologizing to the user
Ask the user if the user want to send the error report to the software dev team
Then ask the user if want to restart the application
Or if the error is a warning or of lesser severity:
Show a simple error code and tell the user that there's the error with that action. Something like: "Error 123 at RequestSalary() Line 2"
The practice I usualy use is:
If the error didn't happen due to user error, then you should try to handle the error quietly.
If the error occurred because of some external problem (such as no internet connection) then you should alert the user.
IMO you should show a message (albeit a user friendly one and not something like "java.io.IOException: Connection timed out".) You could have a message box telling the user that an error occured while getting the data and provide helpful tips like: Trying after some time, check network cable, etc.
Also allow user to report that error to you (error reporting build into the app) that will send you the actual error and stack trace.