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InvalidParameterException occurs and WO function incorrectly



InvalidParameterException occurs and the work objects function incorrectly.

Error Messages

Caused by: property .pyRequestParams was expected to have a List or Page mode, but attributes are @Z:J?N:. Details: Invalid value for aAttr passed to, String, char, StorageStream, List) 

Steps to Reproduce


Root Cause

An issue in the custom application code or rules.
The pyRequestParams  are in each flow of the work objects; however, the client did not respond.


Here’s the explanation for the reported behavior:

In the Create case activity, a call is made to a SOAP Service. When the SOAP call is invoked, the Java objects from the Parameter page (pyRequestParams) are copied to local variables. However, the Java objects are not removed from the Parameter page.

The Process Engine copies all the parameters to the pyFlowParameters. This is process that is used to add the properties to each of the pyFlowParameters page.

When the SOAP service is unavailable, due to the upgrade and certificate issues, the existing cases are updated. As result, work objects are saved with old or corrupt pyRequestParams.

To avoid this, add a step to the activity that invokes the SOAP Connector to remove the values from the Parameter page right after invoking the Connect-SOAP method.

Suggest Edit

Published March 19, 2020 - Updated October 8, 2020

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