Python urllib2 Progress Hook

Question

I am trying to create a download progress bar in python using the urllib2 http client. I've looked through the API (and on google) and it seems that urllib2 does not allow you to register progress hooks. However the older deprecated urllib does have this functionality.

Does anyone know how to create a progress bar or reporting hook using urllib2? Or are there some other hacks to get similar functionality?

Solution 1

Here's a fully working example that builds on Anurag's approach of chunking in a response. My version allows you to set the the chunk size, and attach an arbitrary reporting function:

import urllib2, sys

def chunk_report(bytes_so_far, chunk_size, total_size):
   percent = float(bytes_so_far) / total_size
   percent = round(percent*100, 2)
   sys.stdout.write("Downloaded %d of %d bytes (%0.2f%%)\r" % 
       (bytes_so_far, total_size, percent))

   if bytes_so_far >= total_size:
      sys.stdout.write('\n')

def chunk_read(response, chunk_size=8192, report_hook=None):
   total_size = response.info().getheader('Content-Length').strip()
   total_size = int(total_size)
   bytes_so_far = 0

   while 1:
      chunk = response.read(chunk_size)
      bytes_so_far += len(chunk)

      if not chunk:
         break

      if report_hook:
         report_hook(bytes_so_far, chunk_size, total_size)

   return bytes_so_far

if __name__ == '__main__':
   response = urllib2.urlopen('http://www.ebay.com');
   chunk_read(response, report_hook=chunk_report)

Solution 2

Why not just read data in chunks and do whatever you want to do in between, e.g. run in a thread, hook into a UI, etc etc

import urllib2

urlfile = urllib2.urlopen("http://www.google.com")

data_list = []
chunk = 4096
while 1:
    data = urlfile.read(chunk)
    if not data:
        print "done."
        break
    data_list.append(data)
    print "Read %s bytes"%len(data)

output:

Read 4096 bytes
Read 3113 bytes
done.

Solution 3

urlgrabber has built-in support for progress notification.