How to get the instance type of an Exception?

Question

I have this code:

try:
    self.client.post(url, data, self.cookies, headers, auth, jsonrpc)
    self.status  = self.client.status
    self.mytime  = self.client.time
    self.text    = self.client.text
    self.length  = len(self.text)
except urllib2.URLError, error:
    print error
    self.exception = True
    self.urrlib2   = True
    if isinstance(error.reason, socket.timeout):
        self.timeout = True

But sometimes I get exceptions printing out like this:

URLError in POST > reason=The read operation timed out > <urlopen error The read operation timed out>

These are handled by the except urllib2.URLError. They should pass the if isinstance(error.reason, socket.timeout) test, but they do not.

So I would like to know what instance this exception is. How can I do this?

`type()` gives you a string representation of an object's type or class. — Martijn Pieters, Jan 16 '13 at 09:10
So you mean I should do `type(error)` here? I have to modify my code, and the exception will take several hours to appear ... Or is it `type(error.reason)` ? — blueFast, Jan 16 '13 at 09:13
`print type(error.reason)` will help you diagnose what type it is; not much of an answer, hence just a comment. — Martijn Pieters, Jan 16 '13 at 09:14
why not!? That *is* the answer (if it works). So I will test it and accept it as answer ... — blueFast, Jan 16 '13 at 09:15
Erm, not a string representation, a type object. Sorry, need some more sleep there. — Martijn Pieters, Jan 16 '13 at 09:16
@ATOzTOA: `urllib2.URLError` objects have a `.reason` attribute. That is what the exception handling is catching. — Martijn Pieters, Jan 16 '13 at 09:18
@gonvaled Your code should work, see this thread: http://stackoverflow.com/questions/2712524/handling-urllib2s-timeout-python — ATOzTOA, Jan 16 '13 at 09:23

score 1 · Accepted Answer · answered Jan 16 '13 at 09:17

1

The type() function returns the type of an object.

You could use print type(error.reason) to diagnose what type of object reason is in this case.

answered Jan 16 '13 at 09:17

Martijn Pieters

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I have found that it is of instance `ssl.SSLError`. I wonder what this has to do with `urllib2.URLError` – blueFast Jan 16 '13 at 09:47
Mmm. I see this http://docs.python.org/2/library/ssl.html. `ssl.SSLError` is of subtype `socket.error` which is of subtype `IOError`. I do not know why it goes through the `except urllib2.URLError, error` code. – blueFast Jan 16 '13 at 09:51
@gonvaled: The `urllib2` code catches that exception, then raises `URLError(originalexception)`, and that argument is stored as `.reason`. – Martijn Pieters Jan 16 '13 at 09:55

score 0 · Answer 2 · answered Jan 16 '13 at 09:45

Use this:

import sys

try:
    self.client.post(url, data, self.cookies, headers, auth, jsonrpc)
    self.status  = self.client.status
    self.mytime  = self.client.time
    self.text    = self.client.text
    self.length  = len(self.text)
except urllib2.URLError, error:
    print error
    self.exception = True
    self.urrlib2   = True

    errno, errstr = sys.exc_info()[:2]
    if errno == socket.timeout:
        print "There was a timeout"
        self.timeout = True

How to get the instance type of an Exception?

2 Answers2