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Report server crashes when a report produces an error.

edited December 2005 in Server
I am using Report Server 9. When a report gets called which produces error
by calculations, the report server crashes. A Range Check error is raised.
After this error, the report server produces an dialog "TRsServer - Fatal
Exception" and stops listening.

Is there any way to catch these errors?

Kind regards,
Mariella

Comments

  • edited December 2005

    -------------------------------------------------------------------------------
    Tech Tip: RB Server - Exception Handling
    -------------------------------------------------------------------------------

    ThiS article applies to processing that occurs on the report server. It does
    not apply to the webtier or client report.

    The report server is a multi-threaded application. Each report executes in a
    separate thread. Exceptions that descend from EReportBuilder are handled
    gracefully by the server - the exception is propogated back to the web tier
    or client report application. A web tier application will display an error
    page, a client report application will raise an exception in the client app.
    In both cases a descriptive message is included.

    An exception that does not descend from EReportBuilder error is considered
    fatal and will cause the server application to terminate. If ReportBuilder
    Services is being used to manage the server, then ReportBuilder Services
    will automatically try to restart the server application.

    ReportBuilder Server contains code to check for common exceptions that occur
    when loading and generating reports. These exceptions are re-raised as
    either EReportBuilder or a descendant of EReportBuilder error.


    Custom code that is added to the server should follow these same guidelines.

    Example:

    uses
    ppTypes;


    // define a custom exception class to use for all of your custom code

    ECustomReportBuilderError = class(EReportBuilderError);


    try
    {some processing here}

    except on E: EStreamError do

    raise ECustomReportBuilderErrorr.Create(E.Message);

    end;


    Note: The above example will trap an EStreamError and re-raise it as
    ECustomReportBuilderError. Other exceptions will be considered fatal.
    Therefore you will have to decide which exceptions are acceptable and which
    are fatal.





    Best regards,

    Nard Moseley
    Digital Metaphors
    www.digital-metaphors.com
  • edited December 2005
    Hi Nard,

    The exception occurs from the report itself. How can I trap these errors, as
    they do not occur in custom code, but in report server and/or report builder
    code?

    Kind regards,
    Mariella
  • edited December 2005

    The RB and RB Server code is structured in such a way that it traps common
    errors and re-raises them as EReportBuilder error so that they can be passed
    back to the client.

    Any other errors in RB code would mean that the application needs to be shut
    down. A properly structured report server application should not be
    encountering crashes. Sounds like you might have issues with thread-safety
    or some other issues.

    From your description, it appears that you may be structuring your
    application in a manner that has never been tested.

    The report server application should be run as a stand alone .exe or within
    the context of ReportBuilder Services (i.e. Windows Service). This is
    described in the RB Server Developers Guide and demonstrated in the
    tutorials and the RB Server Demos. Using this architecture you can
    optionally run the server as a standard Delphi application using the Delphi
    debugger to trace and find exceptions. Embedding the Server and WebTier in
    the same application or .dll has not been tested and I would expect that it
    will fail.

    The WebTier has been tested within the context of ISAPI, Apache, ASP and
    ASP.NET applications. These are all multi-threaded applications that all
    essentially work by building a dynamically loaded module (.dll or .so) and
    passing the web request/response to/from the WebTier.

    report server app <----> web tier app <---> web browser




    Best regards,

    Nard Moseley
    Digital Metaphors
    www.digital-metaphors.com
  • edited December 2005
    Hi Nard,

    The exception appears only to happen in the report server, and not when
    calling the same report from report builder.

    I will investigate further, and let you know when I know more.

    Kind regards,
    Mariella
  • edited December 2005
    Hi Nard,

    Problem appears to be in 3rd Party components which are not able to read an
    empty stream. The failing reports do not exist. Our main application will
    just call a "new" report in that case. Since the method to retrieve the
    reports for the report server is different, the problem only occured in the
    report server.

    Kind regards,
    Mariella

  • edited December 2005

    Ok great.

    Another option is to write some code that retrieves the report catalog (i.e.
    the directory tree of available reports) fom the server. For an example,
    check out RBuilder\Demos\Clients\Dynamic List and Dynamic Menu. I'm thinking
    you could retrieve the report catalog and then check whether a specified
    report exists.

    The WebTier.CreateClientReportCatalog method can create and configure a
    TrsClientReportCatalog instance that you can use.

    uses
    rsWebTier,
    rsWebRequest,
    rsClientReportCatalog;

    var
    lWebRequest: TrsWebRequest;
    lClientReportCatalog: TrsClientReportCatalog;

    lWebRequest := myWebTier.CreateWebRequest(lQueryParams, lContent);

    lClientReportCatalog := myWebTier.CreateClientReportCatalog(lWebRequest);

    {call methods on client report catalog}








    Best regards,

    Nard Moseley
    Digital Metaphors
    www.digital-metaphors.com
  • edited December 2005
    Hi Nard,

    For now I will check if the stream has data, and only process it further
    when its length is greather than 0. It appears to be the only problem, as
    the report server did not crash anymore afterwards on non-existent reports
    or broken reports.

    Thanks for your input, I will see what it can do for me. :)

    Kind regards,
    Mariella

This discussion has been closed.