UnicodeDecodeError: 'utf8' codec can't decode bytes in position 3-6: invalid data

Question

how does the unicode thing works on python2? i just dont get it.

here i download data from a server and parse it for JSON.

Traceback (most recent call last):
  File "/usr/local/lib/python2.6/dist-packages/eventlet-0.9.12-py2.6.egg/eventlet/hubs/poll.py", line 92, in wait
    readers.get(fileno, noop).cb(fileno)
  File "/usr/local/lib/python2.6/dist-packages/eventlet-0.9.12-py2.6.egg/eventlet/greenthread.py", line 202, in main
    result = function(*args, **kwargs)
  File "android_suggest.py", line 60, in fetch
    suggestions = suggest(chars)
  File "android_suggest.py", line 28, in suggest
    return [i['s'] for i in json.loads(opener.open('https://market.android.com/suggest/SuggRequest?json=1&query='+s+'&hl=de&gl=DE').read())]
  File "/usr/lib/python2.6/json/__init__.py", line 307, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python2.6/json/decoder.py", line 319, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.6/json/decoder.py", line 336, in raw_decode
    obj, end = self._scanner.iterscan(s, **kw).next()
  File "/usr/lib/python2.6/json/scanner.py", line 55, in iterscan
    rval, next_pos = action(m, context)
  File "/usr/lib/python2.6/json/decoder.py", line 217, in JSONArray
    value, end = iterscan(s, idx=end, context=context).next()
  File "/usr/lib/python2.6/json/scanner.py", line 55, in iterscan
    rval, next_pos = action(m, context)
  File "/usr/lib/python2.6/json/decoder.py", line 183, in JSONObject
    value, end = iterscan(s, idx=end, context=context).next()
  File "/usr/lib/python2.6/json/scanner.py", line 55, in iterscan
    rval, next_pos = action(m, context)
  File "/usr/lib/python2.6/json/decoder.py", line 155, in JSONString
    return scanstring(match.string, match.end(), encoding, strict)
UnicodeDecodeError: 'utf8' codec can't decode bytes in position 3-6: invalid data

thank you!!

EDIT: the following string causes the error: '[{"t":"q","s":"abh\xf6ren"}]'. \xf6 should be decoded to ö (abhören)

Answer 1

The string you're trying to parse as a JSON is not encoded in UTF-8. Most likely it is encoded in ISO-8859-1. Try the following:

json.loads(unicode(opener.open(...), "ISO-8859-1"))

That will handle any umlauts that might get in the JSON message.

You should read Joel Spolsky's The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!). I hope that it will clarify some issues you're having around Unicode.