What can cause a ClientCertificateValidationMiddleware null reference error in the GetBulkStockInformation?

Question

What can cause the following error log when retrieving stock information from the Commerce Engine?

00186 04:18:52 ERROR ClientCertificateValidationMiddleware: Message = Object reference not set to an instance of an object.
System.NullReferenceException: Object reference not set to an instance of an object.
   at Sitecore.Commerce.Plugin.Inventory.ApiController.<GetBulkStockInformation>d__1.MoveNext()

Is it related to client certificate or can it be any error during processing of the GetBulkStockInformation?

Answer 1

I think it should not be related to client certificate.

Here is the section of code from client certificate validation middleware (taken from XC 9.2):

Notice there are two try/catch blocks, first catch block will be executed for certificate error or some other error. If response code is 401 then error is related to certificate otherwise not.

Second try/catch block is only related to processing of next middleware (which will be commerce engine api call such as GetBulkStockInformation).

If you are using XC 9.2 then error message you mentioned above must be coming from the second try/catch block and it can be any error during processing of the GetBulkStockInformation.