Advanced Topics¶

Restrict Mode¶

PyArmor can obfuscate the scripts in restrict mode.

If the script is obfuscated in restrict mode:

Each function (code object) will not be obfuscated again in runtime
Any other code can not be insert into the obfuscated scripts
The obfuscated module can not be imported from other clear python scripts

For examples, obfuscate foo.py in restrict mode:

pyarmor obfuscate --restrict foo.py

Each function is obfuscated before it’s called. Once it’s executed, it will not be obfuscated again.

And if adding print in the obfuscated script:

from pytransform import pyarmor_runtime
pyarmor_runtime()
__pyarmor__(__name__, __file__, b'...')
print('Something')

It will report error as running:

python foo.py

In a short word, the obfuscated script in restrict mode runs quickly, but maybe less security.

If the scripts is obfuscated in restrict mode, you should enable restrict mode either as generating new licenses for it:

pyarmor licenses --restrict --expired 2019-01-01 mycode

Show License Information¶

Maybe you’d like to show how many days left when you issue an expired license for obfuscated scripts.

Use get_license_info function in the module pytransform.py of Runtime Files to get license information of obfuscated scripts.

Here it’s an example which explains how to do. Suppose there is a script foo.py will be obfuscated and distributed to the customer, it will print expired date and license code, then do something.

The content of foo.py:

def show_license_code():
    from pytransfrom import get_license_info

    info = get_license_info()
    print('This script is only for %s' % info['CODE]')
    print('This script will expired on %s' % info['expired'])

if __name__ == '__main__':
    show_license_code()
    do_something()

Let’s obfuscate foo.py at first:

pyarmor obfuscate foo.py
pyarmor licenses --expired 2019-01-01 Brave-Tom
cp licenses/Brave-Tom/license.lic dist/license.ic

Then run this obfuscated script in the output path dist:

cd dist/
python foo.py

The output will be:

This script is only for Brave-Tom
This script will expired on 2019-01-01