Downloading Image

Question

Hi all,

I used urllib2.build_opener() to download an image from a corresponding url.But for a particular url i am getting error.When i checked that url i came to know that there is no image.How can i check whether there is image or not.This is my code

opener1 = urllib2.build_opener()
page1=opener1.open(orginal)
my_picture=page1.read()

The error i got is

  File "suitcase.py", line 120, in <module>
    get_suitcase()
  File "suitcase.py", line 96, in get_suitcase
    page1=opener1.open(orginal)
  File "D:\Program Files\Python\lib\urllib2.py", line 395, in open
    response = meth(req, response)
  File "D:\Program Files\Python\lib\urllib2.py", line 508, in http_response
    'http', request, response, code, msg, hdrs)
  File "D:\Program Files\Python\lib\urllib2.py", line 433, in error
    return self._call_chain(*args)
  File "D:\Program Files\Python\lib\urllib2.py", line 367, in _call_chain
    result = func(*args)
  File "D:\Program Files\Python\lib\urllib2.py", line 516, in http_error_default

    raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 404: Not Found

How to check image is there and proceed with saving that image

regards

arun

Answer 1

I don't understand. Why just not catch the error with the try and except keywords?

Answer 2

By checking the code attribute of the exception.

Answer 3

as others have suggested catch the exception and check for code e.g.

import urllib2

opener1 = urllib2.build_opener()
try:
    page1=opener1.open("http://www.google.com/nosuchimage")
    my_picture=page1.read()
except urllib2.HTTPError,e:
    if e.code == 404:
        print "no such image"
    else:
        print "error",e
except urllib2.URLError,e:
    print "URLError",e

Answer 4

try:
    page1=opener1.open(orginal)
except HTTPError, e:
    if e.code == 404: # Only one of the many possible errors...
        print "Resource does not exist"
    raise

my_picture=page1.read() 

see also urllib2 - the missing manual