android-compile-check.yml

name: Android Compile Check

# Compiles all app Kotlin (by building the debug APK) on PRs that change Kotlin
# source, to catch Kotlin compile breaks before they reach main. The full signed
# release build (build-android.yml) is workflow_call-only and never runs on PRs,
# so without this gate a Kotlin break (e.g. the bare success() call in #8754)
# could merge undetected.
#
# Scope: the PR trigger runs only on Kotlin (*.kt) changes. It intentionally
# does NOT run on Go/gomobile-AAR or Flutter/dep changes — a Go change that
# breaks the AAR<->Kotlin interface would surface in build-android.yml /
# release, not here. workflow_dispatch exists only for benchmarking/debugging.
#
# Debug build only: no keystore/APP_ENV secrets, no AAB, no artifact upload.

on:
  workflow_dispatch:
  pull_request:
    paths:
      - "**/*.kt"
      # keep the self-trigger so edits to this workflow re-run it
      - ".github/workflows/android-compile-check.yml"

concurrency:
  group: android-compile-check-${{ github.ref }}
  cancel-in-progress: true

jobs:
  compile-check:
    permissions:
      contents: "read"
    runs-on: ubuntu-24.04
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Set up Go
        uses: actions/setup-go@v5
        with:
          go-version-file: "go.mod"
          cache: true

      - name: Cache Flutter dependencies
        uses: actions/cache@v4
        timeout-minutes: 5
        continue-on-error: true
        with:
          path: |
            ~/.pub-cache
          key: ${{ runner.os }}-flutter-${{ hashFiles('**/pubspec.lock') }}
          restore-keys: |
            ${{ runner.os }}-flutter-

      - name: Set up Java 17 (Gradle cache)
        uses: actions/setup-java@v4
        with:
          distribution: temurin
          java-version: 17
          cache: "gradle"
          cache-dependency-path: |
            **/*.gradle*
            **/gradle-wrapper.properties

      - name: Set up Android SDK
        uses: android-actions/setup-android@v3

      - name: Free Linux runner disk
        if: runner.os == 'Linux'
        shell: bash
        run: |
          set -euxo pipefail
          df -h
          sdk_root="${ANDROID_SDK_ROOT:-${ANDROID_HOME:-}}"
          sdk_root="${sdk_root%/}"
          if [[ -z "$sdk_root" || "$sdk_root" == "/" || "$sdk_root" != /* ]]; then
            echo "Android SDK root is not set to a safe absolute path: '${sdk_root}'" >&2
            exit 1
          fi
          # Keep the preinstalled Android platforms/build-tools/CMake/NDK; the
          # shared Makefile defaults match the versions this job needs.
          sudo rm -rf \
            "$sdk_root/emulator" \
            "$sdk_root/system-images" \
            /opt/ghc \
            /opt/hostedtoolcache/CodeQL \
            /usr/local/.ghcup \
            /usr/local/julia* \
            /usr/local/share/boost \
            /usr/share/dotnet \
            /usr/share/swift
          df -h

      - name: Install Android SDK components
        shell: bash
        run: |
          set -euxo pipefail
          make install-android-sdk
          make android-env >> "$GITHUB_ENV"

      - name: Install Flutter
        uses: subosito/flutter-action@v2.22.0
        with:
          channel: stable
          flutter-version-file: .github/flutter-version.yaml
          cache: true

      - name: Set gomobile cache dir
        shell: bash
        run: |
          echo "GOMOBILECACHE=$HOME/.cache/gomobile" >> "$GITHUB_ENV"
          mkdir -p "$HOME/.cache/gomobile"

      - name: Cache gomobile
        uses: actions/cache@v4
        timeout-minutes: 10
        continue-on-error: true
        with:
          path: ~/.cache/gomobile
          key: ${{ runner.os }}-gomobile-${{ hashFiles('**/go.mod', '**/go.sum') }}
          restore-keys: |
            ${{ runner.os }}-gomobile-

      - name: Cache Android AAR
        id: android-aar-cache
        uses: actions/cache@v4
        timeout-minutes: 5
        continue-on-error: true
        with:
          path: |
            bin/android/liblantern.aar
            android/app/libs/liblantern.aar
          key: ${{ runner.os }}-android-aar-${{ hashFiles('go.mod', 'go.sum', 'Makefile', '**/*.go') }}

      - name: Mark restored Android AAR fresh
        if: steps.android-aar-cache.outputs.cache-hit == 'true'
        run: |
          test -s bin/android/liblantern.aar
          test -s android/app/libs/liblantern.aar
          touch bin/android/liblantern.aar android/app/libs/liblantern.aar

      - name: Install dependencies (gomobile)
        if: steps.android-aar-cache.outputs.cache-hit != 'true'
        run: make install-android-deps
        env:
          GOMOBILECACHE: ${{ env.GOMOBILECACHE }}

      - name: Flutter pub get + codegen
        run: |
          make pubget
          make gen

      # app.env is a declared pubspec asset, normally decoded from a secret by
      # the release workflow. This compile-only gate doesn't run the app, so an
      # empty placeholder is enough to satisfy asset bundling without the secret.
      - name: Create placeholder app.env
        run: touch app.env

      # Uses the cached gomobile AAR when possible, then compiles the debug APK
      # (all app Kotlin). A Kotlin compile error fails this step — the whole
      # point of the gate.
      - name: Build debug APK (compiles Kotlin)
        run: make android-debug-ci
        env:
          GOMOBILECACHE: ${{ env.GOMOBILECACHE }}