How to trace QRS API POST errors in Qlik Sense logs, which log file to look at?

Dave-Ampere — Mon, 31 Oct 2022 20:24:05 GMT

Hi, I'm trying to develop some QRS API calls to automate some processes for QlikSense on Windows (Enterprise). GET calls are working OK, but POSTs and PUTs are not. I'm getting a 400 response back but without further information.

As a first step, could you advise me the best place to look in the QlikSense logs for these calls? Also, do the logs need to be at a certain verbosity?

Thanks!

Re: QRS API POST errors - which log file?

Patricia_Silva — Tue, 17 May 2022 13:36:47 GMT

Hello @Dave-Ampere, I would suggest you to set the logs to debug mode. On the other hand have you tried to use Postman tool to see what response you get from there?

Re: QRS API POST errors - which log file?

Dave-Ampere — Tue, 17 May 2022 15:16:43 GMT

Hi @Patricia_Silva , thanks. I do use Postman yes. The response doesn't carry enough information (a 400 code but little else).

Thanks! Your help has helped me crack it:

I worked out it is the "System Level Log" that needed to be set to DEBUG and then I can see more information in the Repository Log folder, in the "Trace > System Repository" log.

From there I could see the JSON payload was causing an exception in QlikSense. With a bit of trial and error I've got my payload JSON correct. Sorted 🙂

Some background details:

I was testing the create flow (POST) to create a new custom property definition (as per the API docs for creating custom property ). Once I'd set the level to Debug, I could see my POST request and then the next line in the logs carries this:

[RESTEngine.HandleException] Caught Newtonsoft.Json.JsonReaderException Unexpected character encountered while parsing value: n. Path '', line 0, position 0. at Newtonsoft.Json.JsonTextReader.ParseValue()↵↓ at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)↵↓ at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)↵↓ at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)↵↓ at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)↵↓ at Qlik.Sense.Common.Serialization.JSONSerializer.Deserialize(String value, Type type, JsonSerializerSettings serializerSettings)↵↓ at Qlik.Sense.Common.Communication.REST.Server.RESTParser.ParseRequest(IHttpListenerRequestWrapper httpRequest, IHttpRecording httpRecording, IObjectCreator objectCreator, ParsedMethod parsedMethod)↵↓ at Qlik.Sense.Common.Communication.REST.Server.RESTEngine.<>c__DisplayClass26_0.<GetParsedRequest>b__0(ParsedMethod parsedMethod)↵↓ at System.Collections.Generic.List`1.ForEach(Action`1 action)↵↓ at Qlik.Sense.Common.Communication.REST.Server.RESTEngine.GetParsedRequest(IHttpListenerRequestWrapper request, IHttpRecording httpRecording, IObjectCreator objectCreator)↵↓ at Qlik.Sense.Common.Communication.REST.Server.RESTEngine.HandleRequest(IHttpListenerRequestWrapper httpRequest, IHttpListenerResponseWrapper httpResponse, IHttpRecording httpRecording)

Re: QRS API POST errors - which log file?

Patricia_Silva — Thu, 19 May 2022 05:32:23 GMT

Hello @Dave-Ampere, I am happy to know the issue could be solved, and also happy that you shared the solution you found 🙂

topic Re: QRS API POST errors - which log file? in Integration, Extension & APIs

How to trace QRS API POST errors in Qlik Sense logs, which log file to look at?

Re: QRS API POST errors - which log file?

Re: QRS API POST errors - which log file?

Re: QRS API POST errors - which log file?