Reliability Problem

Question

hi all,
i have been developping webservices since the last past 7
months, so it's not a "how to" problem.
I hope that someone could maybe help in finding some clues.
Here is my problem:
i have made a webservice, with a java client, and a .NET
Server. Interop works fine. The server sends back the
result, and if the result is an error, it gives the full
error message for explanations. This error message is
initialized to " " (empty) and can only retrieve a
myError.Message().
When i call the webservice, it can work for 5,10 or 20
times, but suddenlty i will get a message "Exception". I
mean, not the full message, just a string "Exception". If
i call back the webservice with the same data, i could get
again an "Exception" or it could work again for 10 times.
So as you can see, it's not easy to reproduce the bug in
order to debug it.
I mean usualy, when it really bugs (like an insert problem
in a database etc...), i get a full message
like "Unexpected end of file from server" or "Must declare
the variable '@EMP_ContactId'". My try/catch deals with
this..
So i have no idea for the reason of this "Exception"
message. No more details, it can bug or work in a random
way... It's not a timeout problem as the server answers,
but it answers "Exception"... I have never seen this
before. A network problem ? a DB problem ? a SOAP problem
(when it's a SOAP problem i usualy get an "I/O Exception
so i don't thinks it's the case here)?
by the way, i have the feeling that this "exception" has more chances to appear when the webservice has not been called since a few minutes.
If i make successive 40 calls, i have no "exception", but if i wait 15 min for the next call (an example), it will give an "exception". and the next call just after will be fine.
maybe this could help you to help me
really weird.
Any help to find a solution would be appreciated.
Regards
Elise
ps: sorry for my coarse english.

Answer 1

hi all, i posted yesterday a question about reliability.
(see bellow).
I found a great clue that could help me, but not enought.
I have a java client calling a .net webservice.
It works fine at 80%. The other 20%, i don't know why, but
suddenly i have an error without explanation.
I now have a trace of the Sub Application_Error(ByVal
sender As Object, ByVal e As EventArgs) :
for those 20% of errors it tells : "Request format is
unrecognized.
at
System.Web.Services.Protocols.WebServiceHandlerFactory.Core
GetHandler(Type type, HttpContext context, HttpRequest
     request, HttpResponse response)
     at
System.Web.Services.Protocols.WebServiceHandlerFactory.GetH
andler(HttpContext context, String verb, String
     url, String filePath)
     at System.Web.HttpApplication.MapHttpHandler
(HttpContext context, String requestType, String path,
String      pathTranslated, Boolean useAppConfig)
     at System.Web.MapHandlerExecutionStep.Execute()
     at System.Web.HttpApplication.ExecuteStep
(IExecutionStep step, Boolean& completedSynchronously)
I would understand if my java code whas not correct, but
if i send again and again the SAME request (same SOAP
content, i made a SOAP trace to be sure), it will work !!!
So the code to generate the soap message is ok.
I noticed that i have more "chance" to get this error when
the IIS server has just been started and the java client
makes the first call. This first call will often get an
error, but all the other call won't get any error. And
suddenly, after 15 min of inactivity, a new error will be
caught (just an example, the process is a bit random and
the error not so easy to reproduce whenever you want).
I putted this code on the production environment, and this
represents 10 errors /day, it's too much
Why is the request format not valid only 20% ofthe time ?it should be always ok or always bad !!!
Is there anybody here that has an information that could
be helpfull ? I would really appreciate
regards
Elise
ps : sorry for my coarse english again. i do by best ;-)