no inputstream?

[John Krukoff]

On Thu, 2008-05-15 at 17:32 -0600, John Krukoff wrote:
> On Thu, 2008-05-15 at 17:11 -0600, John Krukoff wrote:
> > On Thu, 2008-05-15 at 15:35 -0700, max wrote:
> > > On May 15, 6:18 pm, MRAB <goo... at mrabarnett.plus.com> wrote:
> > > > On May 15, 9:00 pm, max <maxwell.newla... at gmail.com> wrote:
> > > >
> > > > > you're right, my java implementation does indeed parse for Id3v2
> > > > > (sorry for the confusion).  i'm using the getrawid3v2() method of this
> > > > > bitstream class (http://www.javazoom.net/javalayer/docs/docs0.4/
> > > > > javazoom/jl/decoder/Bitstream.html) to return an inputstream that then
> > > > > i buffer and parse.  apologies if i misrepresented my code!
> > > >
> > > > > back to python, i wonder if i'm misusing the mutagen id3 module.  this
> > > > > brief tutorial (http://www.sacredchao.net/quodlibet/wiki/Development/
> > > > > Mutagen/Tutorial) leads me to believe that something like this might
> > > > > work:
> > > >
> > > > > from mutagen.mp3 import MP3
> > > > > id3tags = MP3(urllib2.urlopen(URL))
> > > >
> > > > > but this gives me the following TypeError: "coercing to Unicode: need
> > > > > string or buffer, instance found".  does this mean i need to convert
> > > > > the "file-like object" that is returned by urlopen() into a unicode
> > > > > object?  if so, do i just decode() with 'utf-8', or is this more
> > > > > complex?  as of now, doing so gives me mostly "No such file or
> > > > > directory" errors, with a few HTTP 404s.
> > > >
> > > > [snip]
> > > > I think it's expecting the path of the MP3 but you're giving it the
> > > > contents.
> > > 
> > > cool, so how do i give it the path, if not in the form of a URL
> > > string?  maybe this is obvious...
> > > --
> > > http://mail.python.org/mailman/listinfo/python-list
> > 
> > It doesn't look like you can, with mutagen. So, time to find a different
> > library that supports arbitrary file objects instead of only file paths.
> > I'd suggest starting here:
> > http://pypi.python.org/pypi?%3Aaction=search&term=id3&submit=search
> > 
> > Possibly one with actual documentation, since that would also be a step
> > up from mutagen.
> > 
> 
> After a bit of time looking around, looks like nearly all the python id3
> modules expect to work with filenames, instead of file objects.
> 
> I can't vouch for it, and the documentation still looks sparse, but this
> module at least looks capable of accepting a file object:
> http://pypi.python.org/pypi/tagpy
> 
> Looks like it'd be a challenge to build if you're on windows, since it
> depends on an external library.
> 
> Alternately, you could probably create a subclass of the mutagen stuff
> that used an existing file object instead of opening a new one. No idea
> what that might break, but seems like it would be worth a try.
> 
> As last ditch option, could write the first few kb of the file out to a
> temp file and see if mutagen will load the partial file.
> 

Okay, now I'm officially spending too much time looking through this
stuff.

However, looks like the "load" method of the MP3 class is what you'd
want to override to change mutagen's file loading behavior. Probably
pass the URL as the filename, and take a cut & paste version of the
default load method from ID3FileType and change it to use urllib2 to
open it instead of a local file open.

Might work. Might not. No warranty express or implied.
-- 
John Krukoff <jkrukoff at ltgc.com>
Land Title Guarantee Company