ANN: experimental patch to allow importing from file-like objects

[Gordon McMillan]

Gerson Kurz wrote:

> Motivation: Write a customized import that reads data from encrypted
> files. Both execfile() and exec() are limited, if only that that they
> don't mimic the import syntax. 
> 
> Problem: imp.load_module does expect a file object, but you can only
> pass "real" files, not file-like objects. The internal C-code expects
> native FILE* stuff.
> 
> Solution: An experimental patch to the python22.dll that makes this
> possible. Using file-like objects for import opens up a whole new set
> of possibilities, for example you could fetch the code at runtime from
> a database or a socket. 
 
Most people doing something like this don't use imp.load_module.

First you need a code object for the module. If it's source:

  co = compile(open(srcfile, 'r').read()+'\n', srcfile, 'exec')

If it's already compiled (and still fresh etc.)

  stuff = open(bytecodefile, 'rb').read()
  co = marshal.loads(stuff[8:])

Then you need a module object

  mod = imp.new_module(nm)

(You need to set up mod.__file__, mod.__name__ etc. here).
And finally

  sys.modules[fqname] = mod
  exec co in mod.__dict__

This is not to say that I'm against your patch (didn't look 
at it), just that there's another way around the problem.

-- Gordon
http://www.mcmillan-inc.com/