Qlik Sense NPrinting On-Demand Extension does not pass specific Selections

[Sonja_Bauernfeind]

The Qlik Sense NPrinting On-Demand extension correctly installed and configured. It is possible to generate reports without selections or with specific selections, but at least one of the following problems is present:

1. The report is not generated if you apply specific selections: the "Export" table shows "Request failed". The same report can be generated with other selections or without selections.
2. The report is generated, but some of the values in the selections are not present, as if they were not passed. In the logs, it looks like the filter values were not passed and they may appear to be a null value.

Status code and POST response seen when using browsers Develpment Tools, respectively:
...
500 Internal Server Error
...

An unhandled exception occurred; check the log for more information.
...

In the nprinting_WebEngine.log files:
...
Qlik.NPrinting.WebEngine    18.39.6.0    Qlik.NPrinting.WebEngine.ExceptionHandling.GenericTextExceptionHandler    20190331T204620.272+02:00    ERROR    QLIKSERVERName    username    0    0    0    0    0    0    0    0    Unhandled exception in request http://qlikserver1:4996/api/v1/ondemand/requests. ERROR: System.AggregateException: One or more errors occurred. ---> System.ArgumentException: Cannot add/remove field F\<field name> because it has no values and it is not an override nor a void one??Parameter name: fields??   at Qlik.Printing.Filters.Filter.InternalChecksFilterFields(IEnumerable`1 fields)??
...

Environment:

• Qlik Sense Enterprise on Windows  November 2018 or higher
• Qlik NPrinting  November 2018 or higher

Note:

• The Qlik Sense NPrinting On-Demand extension is officially supported by Qlik from the Qlik Sense 2018 November release.
• Any previous 3rd party or Github extensions are NOT supported by Qlik Support

Resolution:

Fix Version

• Qlik Sense April 2019
• Note: This issue have been seen on April 2019, with same symptom and different logs lines (see below). Hence this issue appears to only be fully resolved on even later releases. Such occurrences were confirmed to be resolved on the November 2019 release, but may also be resolve on other newer releases than April 2019 and prior to November 2019:

From the engine logs:
...
Qlik.NPrinting.Engine    19.9.5.0    Qlik.NPrinting.Engine.Consumer.ContentRequestExecutor    20191206T182635.159-03:00    WARN    QLIKSERVER1        0    0    b5ca8639-7868-4634-8cf4-a55298b6323c    0    cabe39ca-ba19-4bff-8714-b3632695d29d    0    47e28bf5-0775-45f4-8721-2606fce04860    0    Exception during content resolution while processing request {"FilterSequenceToMaterialize":{"Filters":[{"Fields":[{"Name"
...

Note1:

• Recreate any affected custom Qlik Sense On Demand objects if you still experience the issue after upgrading to QS Feb. 2019 Patch 1.
• Also visit the following article for other potential solution: How to manage Qlik Sense NPrinting On Demand "Request Failed" message