Last Updated: 22 Jun 2021 10:52 by ADMIN
Created on: 15 Jun 2021 13:14
Type: Bug Report
Telerik Report Designer: Web Service Datasource throws Null reference exception on valid JSON


I am using Telerik Report Designer

I have created a Web Service Datasource:

The returned Raw String in Preview Data in the Wizard:


 "Ordinal": 0,
 "Cardinality": 1,
 "Tuples": [
     "Ordinal": 0,
     "Members": [
         "Name": "Total ProfitLossBalance"

Everything appears to work, however the Datasource returns an Error:

System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
   bei Telerik.Reporting.Processing.WebServiceDataSource.WebServiceClient.SendCore(IWebServiceRequestSettings settings, AuthenticationHeaderValue authHeader, HttpClient httpClient, HttpClientHandler httpClientHandler)
   bei Telerik.Reporting.Processing.WebServiceDataSource.WebServiceClient.Request(WebServiceDataSource processedDS)
   bei Telerik.Reporting.Processing.WebServiceDataSource.WebServiceDataProvider.GetRemoteRawData(WebServiceDataSource processedDS)
   bei Telerik.Reporting.Processing.WebServiceDataSource.WebServiceDataProvider.get_RawData()
   bei Telerik.Reporting.Processing.WebServiceDataSource.WebServiceSchemaAdapter.AddDataMeasures(SimpleDataModel model)
   bei Telerik.Reporting.Processing.Data.SimpleSchemaAdapterBase.Fill(SimpleDataModel model)
   bei Telerik.Reporting.Processing.Data.SimpleDataProvider`1.GetSchemaCore()
   bei Telerik.Reporting.Processing.Data.DataProvider`1.Telerik.Reporting.Processing.Data.IDataProvider.GetSchema()
   bei Telerik.Reporting.Data.Design.DataSourceService.GetLocalSchema(IDataSource datasource, IDataProviderContext dataProviderContext)
   bei Telerik.Reporting.Data.Design.DataSourceDesignerBase.Telerik.Reporting.Design.Interfaces.IDataSchemaProvider.GetSchema()
   bei Telerik.Reporting.Data.Design.DataSourceService.GetSchemaFromContext(Object context)
   bei Telerik.Reporting.Data.Design.DataSourceService.Telerik.Reporting.Design.Interfaces.IDataSourceService.GetCurrentDataItemSchema(Boolean getFromParentRecursively)
   bei Telerik.Reporting.Design.DataExplorerControl.<>c__DisplayClass2.<RefreshDataSource>b__0()
1 comment
Posted on: 22 Jun 2021 10:52

Hello Constantin,

Thank you for the provided information.

If I understand correctly, when setting up the WebServiceDataSource component through the wizard, in the last step when you preview the data is returned correctly but when you use that data source in the project and then preview the report, it is returning this error message, is that correct?

Based on the image, there are 2 parameters being used, perhaps their runtime and design-time values are not the same and the runtime values are incorrect or missing, please test making both values the same and test again.

Also, does the API work when you use it with a tool like postman, for example? Which report designer do you use?

Please have a look at the Using Parameters with the WebServiceDataSource component article and make sure that everything is set up correctly.

Since the wizard's preview, the data is returned as expected, I think that something is not set up correctly and the issue is not actually a bug and thus I will change the status to Declined.

If you need further help, you may make a forum post where we can continue this discussion and if in the end, it turns out to be a bug, we will log it.

Thank you for using Telerik Reporting!

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