Download excel file from web?

[Guilherme Polo]

On Mon, Jul 28, 2008 at 8:04 PM, patf at well.com <patf at well.com> wrote:
> On Jul 28, 3:52 pm, "Guilherme Polo" <ggp... at gmail.com> wrote:
>> On Mon, Jul 28, 2008 at 7:43 PM, p... at well.com <p... at well.com> wrote:
>> > On Jul 28, 3:33 pm, "p... at well.com" <p... at well.com> wrote:
>> >> On Jul 28, 3:29 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
>>
>> >> > p... at well.com schrieb:
>>
>> >> > > On Jul 28, 3:00 pm, "p... at well.com" <p... at well.com> wrote:
>> >> > >> Hi - experienced programmer but this is my first Python program.
>>
>> >> > >> This URL will retrieve an excel spreadsheet containing (that day's)
>> >> > >> msci stock index returns.
>>
>> >> > >>http://www.mscibarra.com/webapp/indexperf/excel?priceLevel=0&scope=0&...
>>
>> >> > >> Want to write python to download and save the file.
>>
>> >> > >> So far I've arrived at this:
>>
>> >> > >> [quote]
>> >> > >> # import pdb
>> >> > >> import urllib2
>> >> > >> from win32com.client import Dispatch
>>
>> >> > >> xlApp = Dispatch("Excel.Application")
>>
>> >> > >> # test 1
>> >> > >> # xlApp.Workbooks.Add()
>> >> > >> # xlApp.ActiveSheet.Cells(1,1).Value = 'A'
>> >> > >> # xlApp.ActiveWorkbook.ActiveSheet.Cells(2,1).Value = 'B'
>> >> > >> # xlBook = xlApp.ActiveWorkbook
>> >> > >> # xlBook.SaveAs(Filename='C:\\test.xls')
>>
>> >> > >> # pdb.set_trace()
>> >> > >> response = urllib2.urlopen('http://www.mscibarra.com/webapp/indexperf/
>> >> > >> excel?
>> >> > >> priceLevel=0&scope=0&currency=15&style=C&size=36&market=1897&asOf=Jul
>> >> > >> +25%2C+2008&export=Excel_IEIPerfRegional')
>> >> > >> # test 2 - returns check = False
>> >> > >> check_for_data = urllib2.Request('http://www.mscibarra.com/webapp/
>> >> > >> indexperf/excel?
>> >> > >> priceLevel=0&scope=0&currency=15&style=C&size=36&market=1897&asOf=Jul
>> >> > >> +25%2C+2008&export=Excel_IEIPerfRegional').has_data()
>>
>> >> > >> xlApp = response.fp
>> >> > >> print(response.fp.name)
>> >> > >> print(xlApp.name)
>> >> > >> xlApp.write
>> >> > >> xlApp.Close
>> >> > >> [/quote]
>>
>> >> > > Woops hit Send when I wanted Preview.  Looks like the html [quote] tag
>> >> > > doesn't work from groups.google.com (nice).
>>
>> >> > > Anway, in test 1 above, I determined how to instantiate an excel
>> >> > > object; put some stuff in it; then save to disk.
>>
>> >> > > So, in theory, I'm retrieving my excel spreadsheet with
>>
>> >> > > response = urllib2.urlopen()
>>
>> >> > > Except what then do I do with this?
>>
>> >> > > Well for one read some of the urllib2 documentation and found the
>> >> > > Request class with the method has_data() on it.  It returns False.
>> >> > > Hmm that's not encouraging.
>>
>> >> > > I supposed the trick to understand what urllib2.urlopen is returning
>> >> > > to me; rummage around in there; and hopefully find my excel file.
>>
>> >> > > I use pdb to debug.  This is interesting:
>>
>> >> > > (Pdb) dir(response)
>> >> > > ['__doc__', '__init__', '__iter__', '__module__', '__repr__', 'close',
>> >> > > 'code', '
>> >> > > fileno', 'fp', 'geturl', 'headers', 'info', 'msg', 'next', 'read',
>> >> > > 'readline', '
>> >> > > readlines', 'url']
>> >> > > (Pdb)
>>
>> >> > > I suppose the members with __*_ are methods; and the names without the
>> >> > > underbars are attributes (variables) (?).
>>
>> >> > No, these are the names of all attributes and methods. read is a method,
>> >> > for example.
>>
>> >> right - I got it backwards.
>>
>> >> > > Or maybe this isn't at all the right direction to take (maybe there
>> >> > > are much better modules to do this stuff).  Would be happy to learn if
>> >> > > that's the case (and if that gets the job done for me).
>>
>> >> > The docs (http://docs.python.org/lib/module-urllib2.html) are pretty
>> >> > clear on this:
>>
>> >> > """
>> >> > This function returns a file-like object with two additional methods:
>> >> > """
>>
>> >> > And then for file-like objects:
>>
>> >> >http://docs.python.org/lib/bltin-file-objects.html
>>
>> >> > """
>> >> > read(   [size])
>> >> >      Read at most size bytes from the file (less if the read hits EOF
>> >> > before obtaining size bytes). If the size argument is negative or
>> >> > omitted, read all data until EOF is reached. The bytes are returned as a
>> >> > string object. An empty string is returned when EOF is encountered
>> >> > immediately. (For certain files, like ttys, it makes sense to continue
>> >> > reading after an EOF is hit.) Note that this method may call the
>> >> > underlying C function fread() more than once in an effort to acquire as
>> >> > close to size bytes as possible. Also note that when in non-blocking
>> >> > mode, less data than what was requested may be returned, even if no size
>> >> > parameter was given.
>> >> > """
>>
>> >> > Diez
>>
>> >> Just stumbled upon .read:
>>
>> >> response = urllib2.urlopen('http://www.mscibarra.com/webapp/indexperf/
>> >> excel?
>> >> priceLevel=0&scope=0&currency=15&style=C&size=36&market=1897&asOf=Jul
>> >> +25%2C+2008&export=Excel_IEIPerfRegional').read
>>
>> >> Now the question is: what to do with this?  I'll look at the
>> >> documentation that you point to.
>>
>> >> thanx - pat
>>
>> > Or rather (next iteration):
>>
>> > response = urllib2.urlopen('http://www.mscibarra.com/webapp/indexperf/
>> > excel?
>> > priceLevel=0&scope=0&currency=15&style=C&size=36&market=1897&asOf=Jul
>> > +25%2C+2008&export=Excel_IEIPerfRegional').read(1000000)
>>
>> > The file is generally something like 26 KB so specifying 1,000,000
>> > seems like a good idea (first approximation).
>>
>> > And then when I do:
>>
>> > print(response)
>>
>> > I get a whole lot of garbage (and some non-garbage), so I know I'm
>> > onto something.
>>
>> > When I read the .read documentation further, it says that read() has
>> > returned the data as a string object.  Now - how do I convince Python
>> > that the string object is in fact an excel file - and save it to disk?
>>
>> You don't need to convince Python, just write it to a file.
>> More reading for you:http://docs.python.org/tut/node9.html
>>
>> > pat
>> > --
>> >http://mail.python.org/mailman/listinfo/python-list
>>
>> --
>> -- Guilherme H. Polo Goncalves
>
> OK:
>
> response = urllib2.urlopen('http://www.mscibarra.com/webapp/indexperf/
> excel?
> priceLevel=0&scope=0&currency=15&style=C&size=36&market=1897&asOf=Jul
> +25%2C+2008&export=Excel_IEIPerfRegional').read(1000000)
> # print(response)
> f = open("c:\\msci.xls",'w')
> f.write(response)

I would initially change that to:

response = urllib2.urlopen('http://www.mscibarra.com/webapp/indexperf/excel?priceLevel=0&scope=0&currency=15&style=C&size=36&market=1897&asOf=Jul+25%2C+2008&export=Excel_IEIPerfRegional')

f = open("c:\\msci.xls", "wb")
for line in response:
    f.write(line)
f.close()

and then..

>
> OK this makes the file, and there's a c:\msci.xls in place and it's
> about the right size. But whether I make the second param to open 'w'
> or 'wb', when I try to open msci.xls from the Windows file explorer,
> excel tells me that the file is corrupted.

try it.

>
> pat
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
-- Guilherme H. Polo Goncalves