Cannot Parse JSON response

Question

I have a json response as shown below. I am trying to get fileUrl field but unfortunately getting null value.

{
   "errors":false,
   "results":[
      {
         "result":{
            "fileUrl":"/services/data/v42.0/connect/files/12041skfjsdkfs/content?versionNumber=1&_bearer=kjdflkjsdfkljsdklfjsd.asljdklasjdklasfklsnkfslkflkdsf",
            "externalDocumentUrl":null  
            }           
      },
      {
         "result":{
            "fileUrl":"/services/data/v42.0/connect/files/12041skfjsdkfs/content?versionNumber=1&_bearer=kjdflkjsdfkljsdklfjsd.asljdklasjdklasfklsnkfslkflkdsf",
            "externalDocumentUrl":null  
            }           
      }
   ]
}

This is the code i have tried so far.

   map<String, Object> jsonResp =(Map<String, Object>)JSON.deserializeUntyped(response.getBody());
        List<Object> results = (List<Object>)jsonResp.get('results');
        List<Object> result = new List<Object>();
        for(Object obj: results) {
            result.add(obj);
        } 
        Map<String, Object> leftMap =  ( Map<String, Object>) result[0];
        System.debug('LFileUrl=='+leftMap.get('fileUrl'));
        Map<String, Object> rightMap =  ( Map<String, Object>) result[1];
        System.debug('RFileUrl=='+rightMap.get('fileUrl'));

In system.debug, I am getting null value.

So, really cannot get fileUrl value. What have i missed?

Answer 1

EDIT - needed an extra level just as David said.

Pretty sure you just want something like this:

String resp = response.getBody();

Map<String, Object> jsonResp =(Map<String, Object>)JSON.deserializeUntyped(resp);
List<Object> results = (List<Object>)jsonResp.get('results');

for (Object result : results){
  Map<String, Object> resultMap =  ( Map<String, Object>) result;
  Map<String, Object> resultObj =(Map<String, Object>)resultMap.get('result');
  System.debug('fileUrl=='+resultObj.get('fileUrl'));
}

Also have you tried parsing it into a nice typed object using JSON2Apex? Check it out here:

EDIT To test this code (which I have verified works), replace the http response with this static string:

resp = '{"errors":false,"results":[{"result":{"fileUrl":"/services/data/v42.0/connect/files/12041skfjsdkfs/content?versionNumber=1&_bearer=kjdflkjsdfkljsdklfjsd.asljdklasjdklasfklsnkfslkflkdsf","externalDocumentUrl":null}},{"result":{"fileUrl":"/services/data/v42.0/connect/files/12041skfjsdkfs/content?versionNumber=1&_bearer=kjdflkjsdfkljsdklfjsd.asljdklasjdklasfklsnkfslkflkdsf","externalDocumentUrl":null}}]}';

Answer 2

Your code misses a level of structure in the JSON. result contains a list of maps, each of which has exactly one key - 'result'. You need to access this intermediate object to get the 'fileURL' key.