OData PATCH request results in IllegalArgumentException

Question

Since last week we started using SDK version 3.34.1 (and also tested this with 3.35.0). When we send a PATCH request to a SAP service we get a HTTP 204 No-Content response back from our SAP service (SAP Gateway). When the SDK tries to read that response, it tries to parse the response body which is empty. This leads to the following exception:

2020-12-17 16:13:51.767 ERROR 106363 --- [ut.sap.cases]-0] .s.c.s.d.o.c.r.ODataRequestResultGeneric : 
Failed to buffer HTTP response. Unable to buffer HTTP entity.

java.lang.IllegalArgumentException: Wrapped entity may not be null
    at org.apache.http.util.Args.notNull(Args.java:54)
    at org.apache.http.entity.HttpEntityWrapper.<init>(HttpEntityWrapper.java:59)
    at org.apache.http.entity.BufferedHttpEntity.<init>(BufferedHttpEntity.java:59)
    at com.sap.cloud.sdk.datamodel.odata.client.request.ODataRequestResultGeneric.lambda$getHttpResponse$4f00ca4e$1(ODataRequestResultGeneric.java:180)
    at io.vavr.control.Try.of(Try.java:75)
    at com.sap.cloud.sdk.datamodel.odata.client.request.ODataRequestResultGeneric.getHttpResponse(ODataRequestResultGeneric.java:180)
    at com.sap.cloud.sdk.datamodel.odata.client.request.ODataHealthyResponseValidator.requireHealthyResponse(ODataHealthyResponseValidator.java:44)
    at io.vavr.control.Try.andThenTry(Try.java:250)
    at com.sap.cloud.sdk.datamodel.odata.client.request.ODataRequestGeneric.tryExecute(ODataRequestGeneric.java:194)
    at com.sap.cloud.sdk.datamodel.odata.client.request.ODataRequestGeneric.tryExecuteWithCsrfToken(ODataRequestGeneric.java:225)
    at com.sap.cloud.sdk.datamodel.odata.client.request.ODataRequestUpdate.execute(ODataRequestUpdate.java:136)
    at com.sap.cloud.sdk.datamodel.odata.helper.FluentHelperUpdate.executeRequest(FluentHelperUpdate.java:372)
    at com.alliander.gvrn.pmd.adapter.out.sap.cases.SapCasesClient.updateCase(SapCasesClient.java:103)
    at com.alliander.gvrn.pmd.adapter.out.sap.cases.SapCasesClient.persistOn(SapCasesClient.java:81)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at ....

We use generated typed OData V2 client, which are generated by providing our EDMX files a per the SDK documentation.

Below a code snippet of the function that's calling the service. The matrixCase is a autogenerated object. The OData PATCH is properly handled by the SAP service.

private void updateCase(final ExternalId caseId, final PMDFlow pmdFlow, String jwtToken) {
        final HttpDestination sapMatrix = httpDestinationProvider.providePrincipalPropagationDestination(jwtToken);

        // "Create matrixCase object with key
        MatrixCase matrixCase = MatrixCase.builder()
                .psReference(caseId.getValue())
                .build();
        // Set PmdAppControl explicitly, otherwise the generated client doesn't know which fields are updated.
        matrixCase.setPMDAppControl(pmdFlow.getSapNotation());

        try {
            casesService
                    .updateMatrixCase(matrixCase)
                    .executeRequest(sapMatrix);
        } catch (ODataException e) {
            OdataLogger.logODataException(e);
            throw new SapClientException(e);
        }
    }

We've updated to SDK 3.34.1 due to other issues, however before we used 3.32.0 and I don't remember having this issue in version 3.32.0

Any ideas?

Danny

Answer 1

Yes, your observation is correct that 204 represents a valid answer and is not worth logging an error. Hence, the Cloud SDK team will adjust the log entry level to be less alarming.

Regards, Tanvi