Zip file writing progress (callback proc)

[Larry Bates]

durumdara wrote:
> Hi!
> 
> I want to check my zip file writings.
> I need some callback procedure to show a progress bar.
> Can I do that?
> I don't want to modify the PyLib module to extend it, because if I get
> another py, the changes are lost.
> This happening too if I copy the zip module to modify it.
> Any solution?
> 
> Thanks for it:
>    dd

I did this by extending the write method of my zipfile module.

1) Add a callback= keyword argument to __init__ and saving that in
an instance variable (self._callback).

    def __init__(self, file, mode="r", compression=ZIP_STORED,
                 allowZip64=False, callback=None):

        """Open the ZIP file with mode read "r", write "w" or append "a"."""
        self._allowZip64 = allowZip64
        self._didModify = False
        self._callback = callback  # new instance variable to be used in write




2) Change write method so that it calls the progress method of the callback
function after every block is written (if user passed in one).

        while 1:
            buf = fp.read(1024 * 8)
            if not buf:
                break
            file_size = file_size + len(buf)
            #-----New lines follow
	    #
            # Call the progress method of the callback function (if defined)
            #
            if self._callback is not None:
                self._callback.progress(st.st_size, fp.tell())

	    #-----End of new lines
            CRC = binascii.crc32(buf, CRC)
            if cmpr:
                buf = cmpr.compress(buf)
                compress_size = compress_size + len(buf)
            self.fp.write(buf)



3) Define a callback class and use it:

import zipfile

class CB():
    def progress(self, total, sofar):
        zippercentcomplete=100.0*sofar/total
        print "callback.progress.zippercentcomplete=%.2f" % zippercentcomplete
        return

z=zipfile.ZipFile(r'C:\testzip.zip', mode='w', callback=CB())
z.write(r'c:\Library\TurboDelphi\TurboDelphi.exe')

At least by doing it this way you won't break anything if you get a new zipfile
module.  It just won't show progress any more and then you can patch it.

Hope info helps.

-Larry Bates