urlretrieve regression no.2, now in Python 3.3
urlretrieve has a callback parameter, which takes function with the following prototype: def callback(block_number, block_size, total_size): pass Where block_size was constant and block_size*block_number gave an exact number of transferred bytes. Recent change in Python 3.3 changed the semantic of block_size and broke my `wget` package. http://bugs.python.org/issue16409 Can anybody tell me if I can wait for the fix in 3.3.1 or should implement a long-term workaround myself? -- anatoly t.
On 11/7/2012 5:57 AM, anatoly techtonik wrote:
urlretrieve has a callback parameter, which takes function with the following prototype:
def callback(block_number, block_size, total_size): pass
Where block_size was constant and block_size*block_number gave an exact number of transferred bytes.
The 3.2 and 3.3 docs both say "The third argument, if present, is a hook function that will be called once on establishment of the network connection and once after each block read thereafter. The hook will be passed three arguments; a count of blocks transferred so far, a block size in bytes, and the total size of the file. The third argument may be -1 on older FTP servers which do not return a file size in response to a retrieval request." The word 'constant' does not appear. The product is still the same.
Recent change in Python 3.3 changed the semantic of block_size and broke my `wget` package. http://bugs.python.org/issue16409
The only change is that blocksize is now reported as 0 before any blocks have been transmitted. It is a side-effect of commits for http://bugs.python.org/issue10050. -- Terry Jan Reedy
On Wed, Nov 7, 2012 at 2:42 PM, Terry Reedy
On 11/7/2012 5:57 AM, anatoly techtonik wrote:
urlretrieve has a callback parameter, which takes function with the following prototype:
def callback(block_number, block_size, total_size): pass
Where block_size was constant and block_size*block_number gave an exact number of transferred bytes.
The 3.2 and 3.3 docs both say "The third argument, if present, is a hook function that will be called once on establishment of the network connection and once after each block read thereafter. The hook will be passed three arguments; a count of blocks transferred so far, a block size in bytes, and the total size of the file. The third argument may be -1 on older FTP servers which do not return a file size in response to a retrieval request."
The word 'constant' does not appear. The product is still the same.
Recent change in Python 3.3 changed the semantic of block_size and broke my `wget` package. http://bugs.python.org/issue16409
The only change is that blocksize is now reported as 0 before any blocks have been transmitted. It is a side-effect of commits for http://bugs.python.org/issue10050.
two changes. the first block size is 0. the last block size is the number of bytes read. It is a trivial two line change to undo this and I think it would be wise. It is difficult to even find documentation on what the arguments to that callback mean. Look up the urlretrieve() function docs in 2.7 and 3.3 and it doesn't tell you there or refer you to anywhere else to find out. I'm in favor of restoring and documenting the old behavior for this legacy urlretrieve API to make existing code being ported from 2.7 not break. -gps
-- Terry Jan Reedy
_______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/greg%40krypto.org
participants (3)
-
anatoly techtonik -
Gregory P. Smith -
Terry Reedy