Python 3 Android

This is an experimental set of build scripts that will cross-compile the latest Python 3 git master for an Android device.

Build status:

System	Status
Linux (GitLab)

Prerequisites

Building requires:

1. Linux. This project might work on other Unix-like systems but no guarantee.
2. Android NDK r19 beta 1 or newer installed and environment variable $ANDROID_NDK points to its root directory. NDk r18 or below is not supported.
3. git and python3.9 in $PATH. It's recommended to use the latest git-master to build python3.9. Here are some ways to install the python3.9:

• For Arch Linux users, install python-git package from AUR
• For other users, install 3.9 from pyenv

4. (Optional yet highly recommended) Vinay Sajip's python-gnupg package for verifying PGP signatures of source tarballs and patches. You can install it with the following command:

python -m pip install --user python-gnupg

If pip is not installed, the ensurepip module is your friend:

python -m ensurepip --user

Running requires:

1. Android 5.0 (Lollipop, API 21) or above
2. arm, arm64, x86 or x86-64
3. A busybox binary at /data/local/tmp/busybox

Build

1. make clean for good measure.
2. For every API Level/architecture combination you wish to build for:
   • Edit pybuild/env.py to match your (desired) configuration.
   • make to build everything!

Build using Docker

pushd docker && docker build -t python3-android-base . && popd
docker run --rm -it --user $(id -u):$(id -g) -v $(pwd):/python3-android python3-android-base

Installation

1. Make sure adb shell works fine
2. Copy all files in build/sysroot to a folder on the device (e.g., /data/local/tmp/python3). Note that on most devices /sdcard is not on a POSIX-compliant filesystem, so the python binary will not run from there.
3. In adb shell:

cd /data/local/tmp
. ./python3/tools/env.sh
python3.9

And have fun!

SSL/TLS

SSL certificates have old and new naming schemes. Android uses the old scheme yet the latest OpenSSL uses the new one. If you got CERTIFICATE_VERIFY_FAILED when using SSL/TLS in Python, you need to generating certificate names of the new scheme:

python3.9 ./python3/tools/c_rehash.py

Check SSL/TLS functionality with:

python3.9 ./python3/tools/ssl_test.py

Known Issues

No big issues! yay