Python-for-android: Can't build a package with bcrypt as requirement

[Cheaterman]

Everything is in the title. If you attempt to build a package with bcrypt in the requirements, you'll get an error when it tries to import the "encodings" module.

[Cheaterman]

This is due to SDL2 build blacklist: /pythonforandroid/bootstraps/sdl2/build/blacklist.txt

[Cheaterman]

Adding the relevant files to a custom whitelist.txt doesn't seem to solve everything however, as now it fails on hashlib. Adding pycrypto to requirements doesn't seem to help.

[Cheaterman]

This possibly runs quite deep and has been going on for a long time: https://stackoverflow.com/questions/24256134/using-hashlib-with-kivy-buildozer

[Cheaterman]

https://github.com/kivy/python-for-android/issues/1260 this told me to add openssl to requirements, which I did. Now, I get a ModuleNotFoundError: No module named 'binascii' from hostpython3/Lib/zipfile.py...

[Cheaterman]

Erf. A buildozer android clean debug seems to have fixed this one. :-)

So in short, it seems the only required steps are to add openssl to requirements in buildozer.spec, and manage the whitelist.txt to revert the blacklisted encodings.

The file looks as follows:

lib-dynload/*codec*
encodings/cp*.pyo
encodings/tis*
encodings/shift*
encodings/bz2*
encodings/iso*
encodings/undefined*
encodings/johab*
encodings/p*
encodings/m*
encodings/euc*
encodings/k*
encodings/unicode_internal*
encodings/quo*
encodings/gb*
encodings/big5*
encodings/hp*
encodings/hz*

And in buildozer.spec:
android.whitelist_src = whitelist.txt

The exact name of the config entry might be different in the future, I know it has changed in the past.

[Cheaterman]

Oops: ImportError: dlopen failed: "/data/data/com.digitalfactoryparis.scs.app/files/app/_python_bundle/site-packages/bcrypt/_bcrypt.so" is 64-bit instead of 32-bit

I think I'll have to build a recipe, hehe.

[Cheaterman]

Here's the recipe I created for BCrypt - it's probably not optimal by any means, but hey, WorksForMe™ so I guess it's GoodEnough™ ? :-)
("created" is an overstatement, it's basically copypasta from CryptographyRecipe hehe)

from pythonforandroid.recipe import CompiledComponentsPythonRecipe, Recipe


class BCryptRecipe(CompiledComponentsPythonRecipe):
    name = 'bcrypt'
    version = '3.1.7'
    url = 'https://github.com/pyca/bcrypt/archive/{version}.tar.gz'
    depends = ['openssl', 'cffi']
    call_hostpython_via_targetpython = False

    def get_recipe_env(self, arch):
        env = super(BCryptRecipe, self).get_recipe_env(arch)

        openssl_recipe = Recipe.get_recipe('openssl', self.ctx)
        env['CFLAGS'] += openssl_recipe.include_flags(arch)
        env['LDFLAGS'] += openssl_recipe.link_dirs_flags(arch)
        env['LIBS'] = openssl_recipe.link_libs_flags()

        return env


recipe = BCryptRecipe()

[AndreMiras]

Great work :clap:
Why don't you pull request it?

[Cheaterman]

Sorry man hectic time at work, coming very soon 😁

[Cheaterman]

Also it doesn't include the whitelist in the recipe and I'm not quite sure
how to achieve that so your input is welcome 😊

[AndreMiras]

No rush, you already provided the solution in this ticket. So if people are in a urge to see it in the tree, they know what to do :smile:
As for the whitelist, I think it could also just be a docstring comment in the recipe listing the modules that need to be whitelisted and pointing to this issue.
Good luck at work

[tomgold182]

I also had the
Oops: ImportError: dlopen failed: "/data/data/com.digitalfactoryparis.scs.app/files/app/_python_bundle/site-packages/bcrypt/_bcrypt.so" is 64-bit instead of 32-bit

issue!
Trying to compile now with your new recipe

[Cheaterman]

I don't think this will work with arm64-v8a builds yet, I need to fix this properly at some point, can anyone provide some feedback on this? Thanks in advance :-)

[ZurMaD]

I also had the
Error: dlopen failed: "/data/data/com.pablogod.eica.eica/files/app/_python_bundle/site-packages/bcrypt/_bcrypt.so" is 64-bit instead of 32-bit
How can I fix it guys?
Some useful information:

Please, can you explain what's a recipe and where I need to compile?

[tomgold182]

@ZurMaD check this
https://python-for-android.readthedocs.io/en/latest/recipes/#creating-your-own-recipe
Let me know if you need more help.