sending NaN in json

Solution 1:

json.dumps has an allow_nan parameter, which defaults to True.

NaN, Infinity and -Infinity are not part of JSON, but they are standard in Javascript, so they're commonly used extensions. If the recipient can't handle them, set allow_nan=False. But then you'll get ValueError when you try to serialise NaN.

Solution 2:

The simplejson package on which Python's standard json package is based moves more quickly, and handles this situation. NaN is not valid JSON, and the ignore_nan flag will handle correctly all NaN to null conversions.

import simplejson as json
json.dumps(thing, ignore_nan=True)

The default parameter will allow simplejson to parse your datetimes correctly.

json.dumps(response, ignore_nan=True, default=datetime.datetime.isoformat)

simplejson can be installed with pip.

pip install simplejson

Solution 3:

NaN is not a valid JSON symbol, see the spec at http://json.org/

Your encoder should probably have encoded the NaN as null instead.