Question

object = {'score-set': [('SomeString', 1.0)], 'n': 10, 'num-found': 1, 'start': 0}
type(object) is dict. 

When I do this in the command line
json.dump(object,f)

where f is an writable open file. I get the dump in the file perfectly.

But inside a program in a context like this:

def JSONresponse(object,request,jsonIndent=None):
    r=HttpResponse(mimetype="application/json")
    callback1=request.GET["jsoncallback"] if "jsoncallback" in request.GET else None
    callback2=request.GET["callback"] if "callback" in request.GET else None
    callback = callback1 or callback2
    if callback and len(callback) > 1:
        r.write(callback + "(")
        json.dump(object,r,indent=jsonIndent)
        r.write(");")
    else:
        json.dump(object,r,indent=jsonIndent)
        r.write("\n")
    return r

I get the following exception on the json.dump line.

Exception Value: 1.0 is not JSON serializable

Any hints would be much appreciated,

Thanks a lot,

Answer 1

I’m guessing your float isn’t really a float, but acts like it in certain ways. Try converting it to a float before serializing it:

object['score-set'] = [(a, float(b)) for (a, b) in object['score-set']]