HTML Nprinting Report Failure in generation

[EISSA]

Dear all,

We are facing a very weird error when sending an html report using Nprinting. (check below screenshot)

The weird thing is that this report is sent on daily basis and most of the time over 95% it will send the report successfully but suddenly without any error on QS tasks we receive this error in the Nprinting Task :

Failed generation of report 1a9f8b4c-b9f0-4416-89d3-e863f6b1da42 for user 07658320-8c0e-4884-a678-ecbc346def0c. ERROR: Exception during content resolution while processing request with id 0249bb54-0e36-44bf-b8ce-b5c325f92ad2. Check Engine logs for details. ERROR: Value cannot be null. Parameter name: value

As first thing we did is that we added the below in the send out script (we use API script to trigger the Nprinting tasks)

// Sleeping time parameter added to avoid sending the data check report empty from Nprinting

SET vLocalSleepTimeInMinutes        = 1; // Enter the sleep time in minutes here

SET vLocalSleepTimeInMiliseconds    = $(vLocalSleepTimeInMinutes) * 60 * 1000; // 60 (sec) = 1 minute

        Sleep $(vLocalSleepTimeInMiliseconds);

So in this case we are granting 1 minute time for the app (qvf) that we are using to generate the HTML to save on the server before sending the report empty.

the above solution worked well for more than 2 weeks then today the error showed again.

Note : After we receive this error all we have to do is to run again the task on QS to trigger the task in Nprinting and the report will be sent successfully without any error. 

Thanks for your support 🙂 

[Ruggero_Piccoli]

Hi,

Did you check the Engine logs? Could you post the errors you find there?

I also suggest to refresh the connection cache and run the Check Entities button from the Designer to be sure all entities used in the report template are still available in the source app. Be also sure you are not applying filters that generates empty dataset.

Best REgards,

Ruggero

[EISSA]

Hi Ruggero,

Thanks for your reply.

Regarding The Engine logs error I found the below in the Engine nprinting_engine.log  :

ERROR: System.ArgumentNullException: Value cannot be null.↓↓Parameter name: value↓↓ at Google.Protobuf.ProtoPreconditions.CheckNotNull[T](T value, String name)↓↓ at ReportingWebRenderer.SnapshotRequest.set_WorkerPoolGuid(String value)↓↓ at Engine.Navigator.QlikSense.SDK.Rendering.MashupGrpcServerUpdated.PrepareSnapshotRequest(RenderParams renderParams, SnapshotRequest& snapshotRequest, RequestMapParameters& requestMapParameters)↓↓ at Engine.Navigator.QlikSense.SDK.Rendering.MashupGrpcServerUpdated.PrepareAndStreamRequest(RenderParams renderParams, CancellationToken token, RequestMapParameters& requestMapParameters)↓↓ at Engine.Navigator.QlikSense.SDK.Rendering.MashupGrpcServerUpdated.Render(RenderParams renderParams)↓↓ at Engine.Navigator.QlikSense.SDK.Rendering.RenderingManager.Render(SenseApp doc, Guid navRequestId, String appId, String identity, String typeId, String objId, Int32 width, Int32 height, Int32 dpi, Double zoom, Int32 timeout)↓↓ at Engine.Navigator.QlikSense.SDK.SenseApp.ExportToImage(IGenericObject sheetObject, Guid requestId, Dictionary`2 propertyValues, Int32 width, Int32 height, Int32 dpi, Double zoom, KeepAspectRatioStrategy keepAspectRatioStrategy, FallbackStrategy fallbackStrategy)

The Error is not clear where I should check further.

Connection cache and  Check Entities are refreshed and checked and nothing changed there.

Regarding the Filters there is no Filters applied for this Report or for the task itself.

Thanks.

Elie