would be nice: import from archive

[Dan Perl]

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file?
Maybe a python specific file type, let's call it a 'par' file?

It would be useful in packaging an python library. Sure, there's always the
python packages, but a single file instead of a whole directory tree would
be more convenient. I am particularly interested because I am working on a
framework/toolkit and I am using a configuration divided into several
modules. It would be nice to be able to save configurations (combinations
of several modules) into single archive files and then switch between
configurations by pointing to one such archive file.

I am quite new to python so I should ask first whether there is already
something like that, although I did a search already. Or maybe such a
feature has already been discussed somewhere? If this is an original idea,
how can I propose it for future releases?

Dan Perl
(yes, I'm Mr. Perl, but I'm using Python, after all Perl is not my middle
name, it's my last name)

[Anthony Baxter]

On Fri, 27 Aug 2004 17:06:06 GMT, Dan Perl <dp***@rogers.c om> wrote:

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file?
Maybe a python specific file type, let's call it a 'par' file?

Or a zip file, perhaps? See PEP-0273, which was implemented in Python 2.3.

(Hm. 273 isn't up-to-date. This is bad :-(

[Dan Perl]

My bad. Right after posting the message I found the 'Index of Python
Enhancement Proposals (PEPs)'
and there is PEP 273, 'Import Modules from Zip Archives', submitted by
James C. Ahlstrom. Thank you, Jim! And there are even two implementations
already.

Dan

"Dan Perl" <dp***@rogers.c om> wrote in message
news:2S******** ***********@new s01.bloor.is.ne t.cable.rogers. com...

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file?
Maybe a python specific file type, let's call it a 'par' file?

It would be useful in packaging an python library. Sure, there's always the python packages, but a single file instead of a whole directory tree would
be more convenient. I am particularly interested because I am working on a framework/toolkit and I am using a configuration divided into several
modules. It would be nice to be able to save configurations (combinations
of several modules) into single archive files and then switch between
configurations by pointing to one such archive file.

I am quite new to python so I should ask first whether there is already
something like that, although I did a search already. Or maybe such a
feature has already been discussed somewhere? If this is an original idea, how can I propose it for future releases?

Dan Perl
(yes, I'm Mr. Perl, but I'm using Python, after all Perl is not my middle
name, it's my last name)

[Dan Perl]

Yes, I saw that after posting my initial message. Thanks though, Anthony!

Dan

"Anthony Baxter" <an***********@ gmail.com> wrote in message
news:ma******** *************** *************** @python.org...

On Fri, 27 Aug 2004 17:06:06 GMT, Dan Perl <dp***@rogers.c om> wrote:

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file?
Maybe a python specific file type, let's call it a 'par' file?

Or a zip file, perhaps? See PEP-0273, which was implemented in Python 2.3.

(Hm. 273 isn't up-to-date. This is bad :-(

[Sean Ross]

"Dan Perl" <dp***@rogers.c om> wrote in message
news:2S******** ***********@new s01.bloor.is.ne t.cable.rogers. com...

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file? [snip] I am quite new to python so I should ask first whether there is already
something like that, although I did a search already. Or maybe such a
feature has already been discussed somewhere? If this is an original idea, how can I propose it for future releases?

Well, you can use .zip files
http://www.python.org/doc/2.3.4/whatsnew/node5.html
HTH,
Sean

[Alex Martelli]

Dan Perl <dp***@rogers.c om> wrote:

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file?
Python 2.3 lets you import modules from a zipfile. The zip format is
better than tar when you just need to get one file from it, which is why
java's jar files are also basically zipfiles.
I am quite new to python so I should ask first whether there is already
something like that, although I did a search already. Or maybe such a
feature has already been discussed somewhere? If this is an original idea,
how can I propose it for future releases?

It's there already, and has been for over a year now;-).
Alex

[Anthony Baxter]

On Fri, 27 Aug 2004 17:15:49 GMT, Dan Perl <dp***@rogers.c om> wrote:

My bad. Right after posting the message I found the 'Index of Python
Enhancement Proposals (PEPs)'
and there is PEP 273, 'Import Modules from Zip Archives', submitted by
James C. Ahlstrom. Thank you, Jim! And there are even two implementations
already.

Note that the PEP is not up-to-date. zipimport "just works" in Python
2.3 and Python 2.4. In the following example, we use the -v flag to
show where imports are coming from.

bonanza% cat hello.py
def hello():
print 'hello world'
bonanza% zip hello.zip hello.py
adding: hello.py (deflated 8%)
bonanza% rm hello.py
bonanza% python2.4 -v
Python 2.4a2 (#3, Aug 24 2004, 01:25:51)
[GCC 3.4.0 20040613 (Red Hat Linux 3.4.0-5)] on linux2
Type "help", "copyright" , "credits" or "license" for more information.
... lots and lots of lines showing default imports snipped ...

import hello Traceback (most recent call last):
File "<stdin>", line 1, in ?
ImportError: No module named hello import sys
sys.path.append ('hello.zip')
import hello # zipimport: found 1 names in hello.zip
dlopen("/usr/local/lib/python2.4/lib-dynload/zlib.so", 2);
import zlib # dynamically loaded from
/usr/local/lib/python2.4/lib-dynload/zlib.so
# zipimport: zlib available
import hello # loaded from Zip hello.zip/hello.py hello.hello()

hello world

At least on this box (linux) there's even a zip file on the default sys.path!

Anthony

[Paul Rubin]

al*****@yahoo.c om (Alex Martelli) writes:

Here is a python feature that I would like: to be able to import modules
from an archive like the jar files in Java. Maybe a regular tar file?

Python 2.3 lets you import modules from a zipfile. The zip format is
better than tar when you just need to get one file from it, which is why
java's jar files are also basically zipfiles.

Jar files are -signed- zip files. Is there some reason to not do that
for Python?

[Dan Perl]

I am using 2.3 and I tried importing from a zip file in a script of my own
and, yes, it works.

I never used the -v flag before but it's great for debugging some problems.
Thanks for mentioning it!

Dan

"Anthony Baxter" <an***********@ gmail.com> wrote in message
news:ma******** *************** *************** @python.org...

Note that the PEP is not up-to-date. zipimport "just works" in Python
2.3 and Python 2.4. In the following example, we use the -v flag to
show where imports are coming from.

[Dan Perl]

----- Original Message -----
From: "Alex Martelli" <al*****@yahoo. com>
Newsgroups: comp.lang.pytho n
Sent: Friday, August 27, 2004 1:37 PM
Subject: Re: would be nice: import from archive

Python 2.3 lets you import modules from a zipfile. The zip format is
better than tar when you just need to get one file from it, which is why
java's jar files are also basically zipfiles.

[...]
It's there already, and has been for over a year now;-).

Alex

Alright, alright! And given the fact that it was added only in 2.3, that
explains why I couldn't find any mention of the feature in 'Python
Cookbook', the 1st ed. I'm looking forward to seeing it mentioned in the
2nd ed. ;-)

Dan