Question

I want Python’s None to be encoded in json as empty string how? Below is the default behavior of json.dumps.

>>> import json
>>> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])
'["foo", {"bar": ["baz", null, 1.0, 2]}]'

Should I overwrite the json encoder method or is there any other way?

Input data is not that simple as in above example, on every request it could be changed to different data structure. Its difficult to write a function for changing data structure.

Answer 1

In the object you’re encoding, use an empty string instead of a None.

Here’s an untested function that walks through a series of nested dictionaries to change all None values to ''. Adding support for lists and tuples is left as an exercise to the reader. 🙂

import copy

def scrub(x):
    ret = copy.deepcopy(x)
    # Handle dictionaries. Scrub all values
    if isinstance(x, dict):
        for k,v in ret.items():
            ret[k] = scrub(v)
    # Handle None
    if x == None:
        ret = ''
    # Finished scrubbing
    return ret