Build Python for Android

Author: FeodorFitsner

.appveyor.yml

@@ -4,13 +4,16 @@ skip_branch_with_pr: true
 environment:
   python_stack: python 3.12
   PYTHON_VERSION: 3.12.6
+  GITHUB_TOKEN:
+    secure: 9SKIwc3VSfYJ5IChvNR74rlTF9BMbAfhCGu1/TmYJBMtC6lkY+UDDkZNK7rC9xnQFUxMrNgoo9kNcNAbKbU8XAcrSwkP2H4mX04FI7P+YbxfiWC8nVHhGNxR4LzO+GO0
 
   matrix:
-    # - job_name: Build Python for Linux
-    #   APPVEYOR_BUILD_WORKER_IMAGE: ubuntu
+    - job_name: Build Python for Android
+      APPVEYOR_BUILD_WORKER_IMAGE: ubuntu-gce-c
+      NDK_VERSION: r27
 
-    - job_name: Build Python for Windows
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
+    # - job_name: Build Python for Windows
+    #   APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
 
 matrix:
   fast_finish: true
@@ -19,19 +22,42 @@ stack: $python_stack
 
 for:
   # ======================================
-  #      Build Python for Linux
+  #      Build Python for Android
   # ======================================
 
   - matrix:
       only:
-        - job_name: Build Python for Linux
+        - job_name: Build Python for Android
 
     install:
-      - echo install
+    - read ver_maj ver_min < <(echo $PYTHON_VERSION | sed -E 's/^([0-9]+)\.([0-9]+).*/\1 \2/')
+    - export PYTHON_VERSION_SHORT="$ver_maj.$ver_min"
 
     build_script:
-      - sh: |
-          echo build
+    - cd android
+
+    # Build all Python ABIs
+    - ./build-all.sh $PYTHON_VERSION
+
+    # Package support package for use with mobile-forge
+    - mkdir -p dist
+    - tar -czf dist/python-android-mobile-forge-$PYTHON_VERSION_SHORT.tar.gz install support
+
+    # Package individual ABIs for use with serious_python Flutter package
+    - ./package-for-dart.sh install $PYTHON_VERSION arm64-v8a
+    - ./package-for-dart.sh install $PYTHON_VERSION armeabi-v7a
+    - ./package-for-dart.sh install $PYTHON_VERSION x86_64
+
+    # Push all archives to artifacts
+    - find dist -maxdepth 1 -type f -iname python-android-*.tar.gz -exec appveyor PushArtifact -DeploymentName python-android {} \;
+
+    test: off
+
+    deploy:
+      provider: GitHub
+      auth_token: $(GITHUB_TOKEN)
+      release: v$(PYTHON_VERSION_SHORT)
+      artifact: python-android
 
   # ======================================
   #      Build Python for Windows

android/.gitignore

@@ -0,0 +1,13 @@
+.envrc
+.vscode/
+build
+dist
+downloads
+install
+local
+support
+*.dist-info
+__pycache__
+*.log
+*.gz
+*.DS_Store

android/README.md

@@ -0,0 +1,33 @@
+# Python for Android
+
+Scripts and CI jobs for building Python 3 for Android.
+
+* Can be run on both Linux and macOS.
+* Build Python 3.12 - specific or the last minor version.
+* Installs NDK r26d or use pre-installed one with path configured by `NDK_HOME` variable.
+* Creates Python installation with a structure suitable for https://github.com/flet-dev/mobile-forge
+
+## Usage
+
+To build the latest minor version of Python 3.12 for selected Android API:
+
+```
+./build.sh 3.12 arm64-v8a
+```
+
+To build all ABIs:
+
+```
+./build-all.sh 3.12
+```
+
+## Credits
+
+Build process depends on:
+* https://github.com/beeware/cpython-android-source-deps
+
+Based on the work from:
+* https://github.com/chaquo/chaquopy/tree/master/target
+* https://github.com/beeware/Python-Android-support
+* https://github.com/beeware/cpython-android-source-deps
+* https://github.com/GRRedWings/python3-android

android/android-env.sh

@@ -0,0 +1,107 @@
+fail() {
+    echo "$1" >&2
+    exit 1
+}
+
+if [[ -z "${NDK_HOME-}" ]]; then
+    NDK_HOME=$HOME/ndk/$NDK_VERSION
+    echo "NDK_HOME environment variable is not set."
+    if [ ! -d $NDK_HOME ]; then
+        echo "Installing NDK $NDK_VERSION to $NDK_HOME"
+
+        if [ $(uname) = "Darwin" ]; then
+            seven_zip=$downloads/7zip/7zz
+            if ! test -f $seven_zip; then
+                echo "Installing 7-zip"
+                mkdir -p $(dirname $seven_zip)
+                cd $(dirname $seven_zip)
+                curl -#OL https://www.7-zip.org/a/7z2301-mac.tar.xz
+                tar -xf 7z2301-mac.tar.xz
+                cd -
+            fi
+
+            ndk_dmg=android-ndk-$NDK_VERSION-darwin.dmg
+            if ! test -f $downloads/$ndk_dmg; then
+                echo ">>> Downloading $ndk_dmg"
+                curl -#L -o $downloads/$ndk_dmg https://dl.google.com/android/repository/$ndk_dmg
+            fi
+
+            cd $downloads
+            $seven_zip x -snld $ndk_dmg
+            mkdir -p $(dirname $NDK_HOME)
+            mv Android\ NDK\ */AndroidNDK*.app/Contents/NDK $NDK_HOME
+            rm -rf Android\ NDK\ *
+            cd -
+        else
+            ndk_zip=android-ndk-$NDK_VERSION-linux.zip
+            if ! test -f $downloads/$ndk_zip; then
+                echo ">>> Downloading $ndk_zip"
+                curl -#L -o $downloads/$ndk_zip https://dl.google.com/android/repository/$ndk_zip
+            fi
+            cd $downloads
+            unzip -oq $ndk_zip
+            mkdir -p $(dirname $NDK_HOME)
+            mv android-ndk-$NDK_VERSION $NDK_HOME
+            cd -
+            echo "NDK installed to $NDK_HOME"
+        fi
+    else
+        echo "NDK $NDK_VERSION is already installed in $NDK_HOME"
+    fi
+else
+    echo "NDK home: $NDK_HOME"
+fi
+
+if [ $host_triplet = "arm-linux-androideabi" ]; then
+    clang_triplet=armv7a-linux-androideabi
+else
+    clang_triplet=$host_triplet
+fi
+
+# These variables are based on BuildSystemMaintainers.md above, and
+# $NDK_HOME/build/cmake/android.toolchain.cmake.
+toolchain=$(echo $NDK_HOME/toolchains/llvm/prebuilt/*)
+export AR="$toolchain/bin/llvm-ar"
+export AS="$toolchain/bin/llvm-as"
+export CC="$toolchain/bin/${clang_triplet}$api_level-clang"
+export CXX="${CC}++"
+export LD="$toolchain/bin/ld"
+export NM="$toolchain/bin/llvm-nm"
+export RANLIB="$toolchain/bin/llvm-ranlib"
+export READELF="$toolchain/bin/llvm-readelf"
+export STRIP="$toolchain/bin/llvm-strip"
+
+# The quotes make sure the wildcard in the `toolchain` assignment has been expanded.
+for path in "$AR" "$AS" "$CC" "$CXX" "$LD" "$NM" "$RANLIB" "$READELF" "$STRIP"; do
+    if ! [ -e "$path" ]; then
+        fail "$path does not exist"
+    fi
+done
+
+# Use -idirafter so that package-specified -I directories take priority. For example,
+# grpcio provides its own BoringSSL headers which must be used rather than our OpenSSL.
+export CFLAGS="-idirafter ${prefix:?}/include"
+export LDFLAGS="-L${prefix:?}/lib -Wl,--build-id=sha1 -Wl,--no-rosegment"
+
+# Many packages get away with omitting this on standard Linux, but Android is stricter.
+LDFLAGS+=" -lm"
+
+case $abi in
+    armeabi-v7a)
+        CFLAGS+=" -march=armv7-a -mthumb"
+        ;;
+    x86)
+        # -mstackrealign is unnecessary because it's included in the clang launcher script
+        # which is pointed to by $CC.
+        ;;
+esac
+
+export PKG_CONFIG="pkg-config --define-prefix"
+export PKG_CONFIG_LIBDIR="$prefix/lib/pkgconfig"
+
+# conda-build variable name
+if [ $(uname) = "Darwin" ]; then
+    export CPU_COUNT=$(sysctl -n hw.ncpu)
+else
+    export CPU_COUNT=$(nproc)
+fi

android/build-all.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+set -eu
+
+python_version=${1:?}
+abis="arm64-v8a armeabi-v7a x86_64 x86"
+
+for abi in $abis; do
+    ./build.sh $python_version $abi
+done