deploying python applications

Question

Is it possible to deploy python applications such that you don't release the source code and you don't have to be sure the customer has python installed?

I'm thinking maybe there is some installation process that can run a python app from just the .pyc files and a shared library containing the interpreter or something like that?

Basically I'm keen to get the development benefits of a language like Python - high productivity etc. but can't quite see how you could deploy it professionally to a customer where you don't know how there machine is set up and you definitely can't deliver the source.

How do professional software houses developing in python do it (or maybe the answer is that they don't) ?

Answer 1

1. You protect your source code legally, not technologically. Distributing py files really isn't a big deal. The only technological solution here is not to ship your program (which is really becoming more popular these days, as software is provided over the internet rather than fully installed locally more often.)

2. If you don't want the user to have to have Python installed but want to run Python programs, you'll have to bundle Python. Your resistance to doing so seems quite odd to me. Java programs have to either bundle or anticipate the JVM's presence. C programs have to either bundle or anticipate libc's presence (usually the latter), etc. There's nothing hacky about using what you need.

3. Professional Python desktop software bundles Python, either through something like py2exe/cx_Freeze/some in-house thing that does the same thing or through embedding Python (in which case Python comes along as a library rather than an executable). The former approach is usually a lot more powerful and robust.

Answer 2

Yes, it is possible to make installation packages. Look for py2exe, cx_freeze and others.

No, it is not possible to keep the source code completely safe. There are always ways to decompile.
Original source code can trivially be obtained from .pyc files if someone wants to do it. Code obfuscation would make it more difficult to do something with the code.