bootstrapping on machines without Python

[M.-A. Lemburg]

Jonathan Hartley wrote:
> While examining py2exe et al of late, my thoughts keep returning to
> the idea of writing, in C or similar, a compiled stand-alone
> executable 'bootstrapper', which:
> 1) downloads and install a Python interpreter if none exists
> 2) runs the application's Python source code using this interpreter.
> 
> An application source code could be distributed with this small exe to
> wrap its top level 'main.py', and the application could then be run on
> machines which do not (yet) have Python installed.
> 
> The goal of this is to provide a way for end-users to download and
> double-click a Python application, without having to know what Python
> is or whether (an appropriate version of) it is installed. This method
> has some disadvantages compared to using py2exe et al, but it has the
> advantage that a small application would remain small: there is no
> need to bundle a whole interpreter with every application.

There are two major issues with such an approach:

 * users will not necessarily like it if a small application
   downloads a several MB from the web somewhere without asking

 * installing applications on Windows typically requires admin
   rights or at least user interaction

I think a good solution to the problem is wrapping the application's
main.py in a batch file which pops up a window to let the user know
that s/he will need to install Python first and point him/her to the
www.python.org web site, if necessary.

Another aspect to consider is whether a py2exe wrapped Python
application is really too big at all.

We ship a rather complex application using py2exe (mxODBC Connect Server)
and the resulting installed footprint is just around 14 MB - that's
roughly the size of a typical YouTube video.

By comparison, a full Python 2.5 installation is around 84 MB and
includes lots of stuff normally not needed for a small
Python application.

> From an
> advocacy point of view, it also must help that merely running such an
> application would seamlessly put a usable Python interpreter installed
> and on the PATH on Windows boxes.
> 
> Even my very limited understanding of the issues is enough to see that
> the idea is far from trivial. I'm aware that great minds are working
> on related and overlapping problems, so I thought I'd ask whether many
> people have done this already, and if not, is there any value in
> taking the trivial first step described above? ie. Ignore all
> complications, and write a simple C program to download & install an
> interpreter, then use that to run my Python.
> 
> In the long run, to be useful for real projects, the bootstrapper
> would need to manage some nasty details:
> * different versions of the interpreter for different applications
> * download required packages
> * manage conflicting versions of packages
> I'm hoping that these thorny problems will be solved, if they aren't
> already, by the great minds working on packaging, etc.
> 
> I'm very aware that I don't know anything at all about this, compared
> to many on the list. Be gentle with me. :-)

-- 
Marc-Andre Lemburg
eGenix.com

Professional Python Services directly from the Source  (#1, Nov 13 2009)
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

::: Try our new mxODBC.Connect Python Database Interface for free ! ::::


   eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
    D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
           Registered at Amtsgericht Duesseldorf: HRB 46611
               http://www.egenix.com/company/contact/