MeshChatX/android

MeshChatX Android App

This directory contains the Android app build configuration using Chaquopy to embed the Python MeshChatX server.

Architecture

The app uses a WebView to display the existing Vue.js frontend. The Python server runs in the background via Chaquopy and serves the web interface on https://127.0.0.1:8000.

Build debug APK

Prerequisites:

• JDK 17 or newer (required by the Android Gradle Plugin used in this project). On distributions with multiple JDKs, point the build at JDK 17+ (for example JAVA_HOME for the Gradle invocation).
• Android SDK with API 34 platform and Build-Tools 34 installed. Set ANDROID_HOME and ANDROID_SDK_ROOT to the SDK root (the same directory for both is fine).
• android/vendor/ must contain the Chaquopy vendor wheels (see Updating Android Python ABI Wheels). The build fails fast if this directory is missing or incomplete.
• MeshChatX Python sources at the repository root (meshchatx/). The build syncs them into the app before compiling.

SDK licenses:

• Use Command-line Tools sdkmanager, not the legacy tools/bin/sdkmanager from old SDK layouts. The legacy tool loads JAXB classes that were removed from the JDK in Java 11, so running it on JDK 17+ fails with NoClassDefFoundError: javax/xml/bind/annotation/XmlSchema.
• Install Command-line Tools if needed: download the package for your OS from Android Studio command-line tools, extract it so you have cmdline-tools/latest/bin/sdkmanager under ANDROID_HOME (the inner folder is often named latest; see Google’s layout for that zip).
• Accept licenses (writes under the SDK; use sudo if the SDK is root-owned):

yes | path/to/cmdline-tools/latest/bin/sdkmanager --licenses

• Install missing packages if the build still complains (platform 34, build-tools 34, etc.):

path/to/cmdline-tools/latest/bin/sdkmanager "platforms;android-34" "build-tools;34.0.0"

Build from the android/ directory:

./gradlew assembleDebug

Debug APK outputs (ABI splits plus universal) are written under app/build/outputs/apk/debug/, for example:

• app-arm64-v8a-debug.apk
• app-x86_64-debug.apk
• app-universal-debug.apk

Updating Android Python ABI Wheels (Python 3.11)

Use this workflow when a dependency (for example cryptography) requires custom Android wheels for arm64-v8a and x86_64.

1. Build wheels in a Podman Python 3.11 container to avoid host Python mismatches:
   • Use docker.io/library/python:3.11-bookworm.
   • Mount project root to /work and Android SDK to /opt/android-sdk.
   • Export ANDROID_HOME and ANDROID_SDK_ROOT to /opt/android-sdk.
   • Example container entry: podman run --rm --network host -e ANDROID_HOME=/opt/android-sdk -e ANDROID_SDK_ROOT=/opt/android-sdk -v "/opt/android-sdk:/opt/android-sdk" -v "<repo>:/work" -w /work docker.io/library/python:3.11-bookworm bash
2. Keep custom Chaquopy recipes in android/chaquopy-recipes/<package>-<major>/:
   • Define package/version in meta.yaml.
   • Store source patches in patches/.
3. Build both ABIs with Chaquopy build-wheel.py and place final wheels in android/vendor/.
4. Update android/app/build.gradle pip installs to the new pinned version.
5. Rebuild with ./gradlew assembleDebug and verify split outputs:
   • app-arm64-v8a-debug.apk
   • app-x86_64-debug.apk
   • app-universal-debug.apk

Notes:

• For Rust-backed wheels (such as modern cryptography), build inside the container with Rust toolchain available.
• Keep recipe files and patches versioned; keep generated build artifacts untracked.

Custom Recipes and Patches

This project keeps Android-specific Chaquopy recipes in android/chaquopy-recipes/ to bridge gaps between desktop Python dependencies and Android wheel availability.

• cryptography-46

  • Purpose: provide Android ABI wheels for cryptography 46.0.7 (arm64-v8a, x86_64) because upstream Chaquopy index only provided older builds.
  • patches/openssl_no_legacy.patch: disables OpenSSL legacy provider loading, which is unavailable in the bundled Android OpenSSL runtime.
  • patches/pyo3_no_interpreter.patch: enables compatible pyo3 ABI settings for Chaquopy Python 3.11 Android builds.

• aiohttp-3.13

  • Purpose: align Android with desktop dependency line (aiohttp 3.13.3) by building fresh ABI wheels with Chaquopy.
  • No source patch is required; recipe pins the newer upstream version for Android wheel generation.

• psutil-7.2

  • Purpose: align Android with desktop dependency line (psutil 7.2.2) while preserving Android runtime behavior.
  • patches/chaquopy.patch: treats android platform as Linux in psutil internals and forces a safe partition enumeration path because /proc/filesystems can be restricted by SELinux on some Android API levels.

• bcrypt-5

  • Purpose: tracks attempted upgrade path to desktop-equivalent bcrypt.
  • Status: currently not enabled in Android app dependencies; bcrypt==3.1.7 remains pinned for stable APK builds.

License

This directory is part of the main project licensing split:

• project-owned portions: 0BSD
• original upstream MeshChat portions: MIT

See ../LICENSE for full text and notices.