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pythonexceptiontypes

How to know which exception type to catch, given the traceback?

A general exception catcher logs the following exception:

Traceback (most recent call last):
  File "4sq.py", line 37, in <module>
    checkin = client.checkins()
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 416, in __call__
    return self.GET('{CHECKIN_ID}'.format(CHECKIN_ID=CHECKIN_ID), params, multi=multi)
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 217, in GET
    return self.requester.GET(self._expanded_path(path), *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 163, in GET
    return self._request(url)
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 200, in _request
    return _request_with_retry(url, data)['response']
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 696, in _request_with_retry
    return _process_request_with_httplib2(url, data)
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 719, in _process_request_with_httplib2
    return _check_response(data)
  File "/usr/local/lib/python2.7/dist-packages/foursquare-20120716-py2.7.egg/foursquare/__init__.py", line 742, in _check_response
    raise exc(meta.get('errorDetail'))
RateLimitExceeded: Quota exceeded

I would like to know the specific exception name so I could add a dedicated catch to it. How can it be found?

Is there a 'type' function on the caught exception or should it be found in the throwing lib's source (available here)?

Solution

  • The exception being raised in the paste is foursquare.RateLimitExceeded (as it says in the final line). You should be able to catch it as normal, or catch its base class foursquare.FoursquareException if you want to handle all errors from the module.

    The code that raises the exception is just looking up which exception class to raise from a dictionary. That shouldn't have any effect on how you catch those errors.