How to make a download with progress bar in Python?

Question

I am trying to implement this package http://code.google.com/p/python-progressbar/ when downloading a file like below:

    def dlProgress(count, blockSize, totalSize):
        widgets = ['Test: ', Percentage(), ' ', Bar(marker=RotatingMarker()), ' ', ETA(), ' ', FileTransferSpeed()]
        pbar = ProgressBar(widgets=widgets, maxval=totalSize).start()
        for count in range(totalSize):
            #print count
            pbar.update(int(count*blockSize*100/totalSize))
        pbar.finish()            
    urllib.urlretrieve(url, fileName, reporthook=dlProgress)

The problem is that the progress bar goes to 100% before the real download progress finished, and it continues to begin the new bar, like this:

Test: 100% |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Time: 0:00:31 402.06 kB/s
Test: 100% |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Time: 0:00:31 408.39 kB/s
Test: 100% |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Time: 0:00:32 389.47 kB/s

Trevor Trevor · Accepted Answer · 2012-06-21T18:26:19

You should initialize your progress bar outside of the progress callback. Then on the first time its called back, check and set the maxval and start it up:

widgets = ['Test: ', Percentage(), ' ', Bar(marker=RotatingMarker()), ' ', ETA(), ' ', FileTransferSpeed()]
pbar = ProgressBar(widgets=widgets)

def dlProgress(count, blockSize, totalSize):
    if pbar.maxval is None:
        pbar.maxval = totalSize
        pbar.start()

    pbar.update(min(count*blockSize, totalSize))

urllib.urlretrieve(url, fileName, reporthook=dlProgress)
pbar.finish()

As a side note, that last block will not be a full block, so you'll want to make sure your not going over the totalSize.

How to make a download with progress bar in Python?

1 Answers