I was wondering if there was a way to use json.loads in order to automatically convert an empty string in something else, such as None.
For example, given:
data = json.loads('{"foo":"5", "bar":""}')
I would like to have:
data = {"foo":"5", "bar":None}
Instead of:
data = {"foo":"5", "bar":""}
You can use a dictionary comprehension:
data = json.loads('{"foo":"5", "bar":""}')
res = {k: v if v != '' else None for k, v in data.items()}
{'foo': '5', 'bar': None}
This will only deal with the first level of a nested dictionary. You can use a recursive function to deal with the more generalised nested dictionary case:
def updater(d, inval, outval):
for k, v in d.items():
if isinstance(v, dict):
updater(d[k], inval, outval)
else:
if v == '':
d[k] = None
return d
data = json.loads('{"foo":"5", "bar":"", "nested": {"test": "", "test2": "5"}}')
res = updater(data, '', None)
{'foo': '5', 'bar': None,
'nested': {'test': None, 'test2': '5'}}
You can also accomplish this with the json.loads object_hook parameter. For example:
import json
import six
def empty_string2none(obj):
for k, v in six.iteritems(obj):
if v == '':
obj[k] = None
return obj
print(json.loads('{"foo":"5", "bar":"", "hello": {"world": ""}}',
object_hook=empty_string2none))
This will print
{'foo': '5', 'bar': None, 'hello': {'world': None}}
This way, you don't need additional recursion.
I did some trial and error and it is impossible to parse
Noneinto a String usingjson.loads()you will have to usejson.loads() with json.dumps()like I do in this example:
import json
data = json.loads('{"foo":"5", "bar":"%r"}' %(None))
data2 = json.loads(json.dumps({'foo': 5, 'bar': None}))
if data2['bar'] is None:
print('worked')
print(data['bar'])
else:
print('did not work')
.replace("\"\"", "None")on the string before loading it into json.