API Connect 5 - Error attempting to read the urlopen response data - api

Question

I'm trying to create a REST API from a SOAP Service using IBM API Connect 5. I have followed all the steps described in this guide (https://www.ibm.com/support/knowledgecenter/en/SSFS6T/com.ibm.apic.apionprem.doc/tutorial_apionprem_expose_SOAP.html).
So, after dragging the web service block from palette, ensuring the correctness of endpoint and publishing the API, I have tried to call the API from the browser. Unfortunately, the API return the following message:
<errorResponse>
<httpCode>500</httpCode>
<httpMessage>Internal Server Error</httpMessage>
<moreInformation>Error attempting to read the urlopen response
data</moreInformation>
</errorResponse>
To testing purpose, I have logged the request and I have tried the request on SOAPUI. The service return the response correctly.
What is the problem?

Answer 1

In my case, the problem was in the backend charset (Content-Type: text/xml;charset=iso-8859-1).
For example, backend returns text/xml in German (or French). Api Connect cannot process character ü. It needs Content-Type: text/xml;charset=UTF-8.

Answer 2

I had a similar issue, in my case was the accept. if you have an Invoke and the content-type or the accept, is not matching the one of the request, or the response that you got, APIC is getting mad.

Answer 3

Please, check if the formats to send (contentType) and receive (accept) are the same of that your API expected. In my case the error occurs because the API returns a String and my default code is configured to receive a JSON body.
//define a JSON-PLAIN TEXT protocol
private HttpEntity<String> httpEntityWithBody(Object objToParse){
HttpHeaders headers = new HttpHeaders();
headers.set("Authorization", "Bearer " + "xxx token xxx");
headers.set("Accept", MediaType.TEXT_PLAIN_VALUE);
headers.setContentType(MediaType.APPLICATION_JSON);
Gson gson = new GsonBuilder().create();
String json = gson.toJson(objToParse);
HttpEntity<String> httpEntity = new HttpEntity<String>(json, headers);
return httpEntity;
}
//calling the API to APIC...
ParameterizedTypeReference<String> responseType = new
ParameterizedTypeReference<String>(){};
ResponseEntity<String> result =
rest.exchange(builder.buildAndExpand(urlParams).toUri(), HttpMethod.PUT, httpEntityWithBody(myDTO), responseType);
String statusCode = result.getStatusCodeValue();
String message = result.getBody();