If you expect to see a JSON response from your HTTP request, it's recommended that you always verify that the HTTP response is indeed a well-formed JSON.
Here is an example checking that JSON has been loaded into the JSON Document:
Define_Com Class(#PRIM_SRVM.HttpClientRequest) Name(#Req)
Define_Com Class(#PRIM_JSON.Document) Name(#JsonDoc) Reference(*DYNAMIC)
...
#Req.DoGet Url('https://maps.googleapis.com/maps/api/geocode/json?...')
* Check if request is successful
If (#Req.Response.IsSuccessHttpStatusCode)
* Place the response into PRIM_JSON.Document
#Req.Response.AsJson Result(#JsonDoc)
If_Ref Com(#JsonDoc) Is_Not(*NULL)
* Good response. JsonDoc is JSON
else
* Bad response. JsonDoc isn't valid
endif
Similar code can be used to validate if the structure of the document is correct. So, before the For/Endfor:
If_Ref Com(#JsonDoc.RootNode<'results'>) Is_Not(*NULL)
For Each(#Result) In(#JsonDoc.RootNode<'results'>)
Endfor
Endif
