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================ RestrictedPython

RestrictedPython is a tool that helps to define a subset of the Python language which allows to provide a program input into a trusted environment. RestrictedPython is not a sandbox system or a secured environment, but it helps to define a trusted environment and execute untrusted code inside of it.

.. warning::

RestrictedPython only supports CPython. It does not support PyPy and other Python implementations as it cannot provide its restrictions there.

For full documentation please see http://restrictedpython.readthedocs.io/.

Example

To give a basic understanding what RestrictedPython does here two examples:

An unproblematic code example

Python allows you to execute a large set of commands. This would not harm any system.

.. code-block:: pycon

>>> from RestrictedPython import compile_restricted
>>> from RestrictedPython import safe_globals
>>>
>>> source_code = """
... def example():
...     return 'Hello World!'
... """
>>>
>>> loc = {}
>>> byte_code = compile_restricted(source_code, '<inline>', 'exec')
>>> exec(byte_code, safe_globals, loc)
>>>
>>> loc['example']()
'Hello World!'

Problematic code example

This example directly executed in Python could harm your system.

.. code-block:: pycon

>>> from RestrictedPython import compile_restricted
>>> from RestrictedPython import safe_globals
>>>
>>> source_code = """
... import os
...
... os.listdir('/')
... """
>>> byte_code = compile_restricted(source_code, '<inline>', 'exec')
>>> exec(byte_code, safe_globals, {})
Traceback (most recent call last):
ImportError: __import__ not found