Arctic Tern Arctic Tern - 4 months ago 374
Python Question

JSON TypeError: expected string or buffer

I'm trying to store an exception error to json. Even though I'm pretty sure I'm storing a string, it's still giving me a typeerror.

Relevant section of code:

except ConnectionError as e:
s = str(e)
print type(s)
data = json.loads({'error message': s})
print "JSON load succeeded"


Traceback:

<type 'str'>

Traceback (most recent call last):
File "[REDACTED]", line 36, in <module>
ping(SERVERS)
File "[REDACTED]", line 29, in ping
data = json.loads({'error message': s})
File "C:\Python27\Lib\json\__init__.py", line 339, in loads
return _default_decoder.decode(s)
File "C:\Python27\Lib\json\decoder.py", line 364, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
TypeError: expected string or buffer


This is quite baffling to me. I'd appreciate any help with this matter.

Answer

You are looking for json.dumps(), not json.loads(). Try this:

    data = json.dumps({'error message': s})

json.dumps(obj): Serialize obj to a JSON formatted str
json.loads(s): Deserialize s (a str instance containing a JSON document) to a Python object