Add full offline Android Gradle Plugin dependency cache

tauri_app/Dockerfile.apk

@@ -60,6 +60,11 @@ RUN sed -i 's/\r$//' tauri_app/docker/*.sh \
 
 ENV ANDROID_AGP_LOCAL_REPO=/opt/android-agp-maven
 ENV GRADLE_USER_HOME=/root/.gradle
+ENV ANDROID_COMPILE_SDK=35
+
+RUN if [ ! -d "${ANDROID_HOME}" ] && [ -d /opt/android-sdk-linux ]; then ln -s /opt/android-sdk-linux "${ANDROID_HOME}"; fi \
+  && ln -sfn android-35 "${ANDROID_HOME}/platforms/android-36" \
+  && test -e "${ANDROID_HOME}/platforms/android-36"
 
 RUN /workspace/tauri_app/docker/prefetch-android-agp.sh \
   && /workspace/tauri_app/docker/verify-offline-agp.sh

tauri_app/docker/patch-android-sdk.sh

@@ -5,6 +5,7 @@ set -euo pipefail
 ANDROID_GEN="${1:-/workspace/tauri_app/src-tauri/gen/android}"
 ANDROID_HOME="${ANDROID_HOME:-/opt/android-sdk}"
 ANDROID_SDK_ROOT="${ANDROID_SDK_ROOT:-${ANDROID_HOME}}"
+GRADLE_USER_HOME="${GRADLE_USER_HOME:-/root/.gradle}"
 
 if [ ! -d "${ANDROID_GEN}" ]; then
   echo "Android project not found: ${ANDROID_GEN}" >&2
@@ -33,10 +34,43 @@ if [ -z "${SDK_LEVEL}" ]; then
   exit 1
 fi
 
-APP_BUILD="${ANDROID_GEN}/app/build.gradle.kts"
+export ANDROID_COMPILE_SDK="${SDK_LEVEL}"
-if [ -f "${APP_BUILD}" ]; then
+
-  sed -i -E "s/compileSdk = [0-9]+/compileSdk = ${SDK_LEVEL}/g" "${APP_BUILD}"
+PLATFORM_DIR="${ANDROID_HOME}/platforms"
-  sed -i -E "s/targetSdk = [0-9]+/targetSdk = ${SDK_LEVEL}/g" "${APP_BUILD}"
+# Tauri 2.x templates/plugins request android-36 while the SDK image ships android-35.
+for requested in 36 35 34; do
+  if [ ! -e "${PLATFORM_DIR}/android-${requested}" ] && [ -d "${PLATFORM_DIR}/android-${SDK_LEVEL}" ]; then
+    ln -sfn "android-${SDK_LEVEL}" "${PLATFORM_DIR}/android-${requested}"
+    echo "==> Platform symlink: android-${requested} -> android-${SDK_LEVEL}"
+  fi
+done
+
+while IFS= read -r -d '' gradle_file; do
+  sed -i -E "s/compileSdk = [0-9]+/compileSdk = ${SDK_LEVEL}/g" "${gradle_file}"
+  sed -i -E "s/targetSdk = [0-9]+/targetSdk = ${SDK_LEVEL}/g" "${gradle_file}"
+  sed -i -E "s/compileSdkVersion = [0-9]+/compileSdkVersion = ${SDK_LEVEL}/g" "${gradle_file}"
+  sed -i -E "s/compileSdkVersion [0-9]+/compileSdkVersion ${SDK_LEVEL}/g" "${gradle_file}"
+  sed -i -E "s/targetSdkVersion = [0-9]+/targetSdkVersion = ${SDK_LEVEL}/g" "${gradle_file}"
+  sed -i -E "s/targetSdkVersion [0-9]+/targetSdkVersion ${SDK_LEVEL}/g" "${gradle_file}"
+done < <(find "${ANDROID_GEN}" \( -name 'build.gradle.kts' -o -name 'build.gradle' \) -print0 2>/dev/null || true)
+
+ROOT_BUILD="${ANDROID_GEN}/build.gradle.kts"
+if [ -f "${ROOT_BUILD}" ] && ! grep -q 'forceOfflineAndroidSdk' "${ROOT_BUILD}"; then
+  cat >> "${ROOT_BUILD}" <<EOF
+
+// forceOfflineAndroidSdk: override compileSdk for Tauri plugin subprojects (offline LAN builds)
+subprojects {
+    afterEvaluate {
+        extensions.findByType(com.android.build.gradle.AppExtension::class.java)?.apply {
+            compileSdk = ${SDK_LEVEL}
+            defaultConfig.targetSdk = ${SDK_LEVEL}
+        }
+        extensions.findByType(com.android.build.gradle.LibraryExtension::class.java)?.apply {
+            compileSdk = ${SDK_LEVEL}
+        }
+    }
+}
+EOF
 fi
 
 GRADLE_PROPS="${ANDROID_GEN}/gradle.properties"
@@ -47,9 +81,49 @@ else
   sed -i 's/^android.builder.sdkDownload=.*/android.builder.sdkDownload=false/' "${GRADLE_PROPS}"
 fi
 
+if ! grep -q '^android.compileSdk=' "${GRADLE_PROPS}"; then
+  printf 'android.compileSdk=%s\n' "${SDK_LEVEL}" >> "${GRADLE_PROPS}"
+else
+  sed -i "s/^android.compileSdk=.*/android.compileSdk=${SDK_LEVEL}/" "${GRADLE_PROPS}"
+fi
+
 cat > "${ANDROID_GEN}/local.properties" <<EOF
 ## Autogenerated for offline Docker build. Do not commit.
 sdk.dir=${ANDROID_HOME}
 EOF
 
+mkdir -p "${GRADLE_USER_HOME}/init.d"
+cat > "${GRADLE_USER_HOME}/init.d/force-android-sdk.gradle" <<EOF
+def offlineCompileSdk = (System.getenv('ANDROID_COMPILE_SDK') ?: '${SDK_LEVEL}').toInteger()
+
+gradle.beforeProject { project ->
+    project.afterEvaluate {
+        def androidExt = project.extensions.findByName('android')
+        if (androidExt == null) {
+            return
+        }
+        try {
+            androidExt.compileSdk = offlineCompileSdk
+        } catch (ignored) {
+            try {
+                androidExt.compileSdkVersion offlineCompileSdk
+            } catch (ignored2) {
+                // ignore non-Android projects
+            }
+        }
+        try {
+            if (androidExt.metaClass.hasProperty(androidExt, 'defaultConfig') && androidExt.defaultConfig != null) {
+                androidExt.defaultConfig.targetSdk = offlineCompileSdk
+            }
+        } catch (ignored) {
+            try {
+                androidExt.defaultConfig.targetSdkVersion offlineCompileSdk
+            } catch (ignored2) {
+                // ignore library modules without targetSdk
+            }
+        }
+    }
+}
+EOF
+
 echo "==> Android SDK patched: compileSdk/targetSdk=${SDK_LEVEL}, sdk.dir=${ANDROID_HOME}, sdkDownload=false"