CODEWITHSUNDEEP
pythondeployment
bph
bph

Reputation: 11258

deploying python applications

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) ?

Upvotes: 14

Views: 10474

Answers (5)

eestrada
eestrada

Reputation: 1603

I am surprised no one mentioned this before now, but Cython seems like a viable solution to this problem. It will take your Python code and transpile it into CPython compatible C code. You also get a small speed boost (~25% last I checked) since it will be compiled to native machine code instead of just Python byte code. You still need to be sure the user has Python installed (either by making it a pre-requisite pushed off onto the user to deal with, or bundling it as part of the installer process). Also, you do need to have at least one small part of your application in pure Python: the hook into the main function.

So you would need something basic like this:

import cython_compiled_module

if __name__ == '__main__':
    cython_compiled_module.main()

But this effectively leaks no implementation details. I think using Cython should meet the criteria in the question, but it also introduces the added complexity of compiling in C, which loses some of Python's easy cross-platform nature. Whether that is worth it or not is up to you.

As others stated, even the resulting compiled C code could be decompiled with a little effort, but it is likely much more close to the type of obfuscation you were initially hoping for.

Upvotes: 6

Mike Graham
Mike Graham

Reputation: 76683

  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.

Upvotes: 19

Oleh Prypin
Oleh Prypin

Reputation: 34116

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.

Upvotes: 8

cha0site
cha0site

Reputation: 10717

Well, it depends what you want to do. If by "not releasing the source code" you mean "the customer should not be able to access the source code in any way", well, you're fighting a losing battle. Even programs written in C can be reverse engineered, after all. If you're afraid someone will steal from you, make them sign a contract and sue them if there's trouble.

But if you mean "the customer should not care about python files, and not be able to casually access them", you can use a solution like cx_Freeze to turn your Python application into an executable.

Upvotes: 3

Matt Alcock
Matt Alcock

Reputation: 12891

Build a web application in python. Then the world can use it via a browser with zero install.

Upvotes: 1

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