ci: add optional release signing from repository secrets

.gitea/workflows/android-build.yml

@@ -1,5 +1,9 @@
 name: Android build
 
+permissions:
+  contents: read
+  releases: write
+
 on:
   push:
     branches:
@@ -33,7 +37,9 @@ jobs:
           export ANDROID_HOME="$ANDROID_SDK_ROOT"
           mkdir -p "$ANDROID_SDK_ROOT/cmdline-tools"
           if [ ! -x "$ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager" ]; then
-            curl -fsSL -o /tmp/commandlinetools.zip https://dl.google.com/android/repository/commandlinetools-linux-12266719_latest.zip
+            tools_url="$(curl -fsSL https://developer.android.com/studio | grep -o 'https://dl.google.com/android/repository/commandlinetools-linux-[0-9][0-9]*_latest.zip' | head -n 1)"
+            test -n "$tools_url"
+            curl -fsSL -o /tmp/commandlinetools.zip "$tools_url"
             rm -rf "$ANDROID_SDK_ROOT/cmdline-tools/latest" "$ANDROID_SDK_ROOT/cmdline-tools/cmdline-tools"
             unzip -q /tmp/commandlinetools.zip -d "$ANDROID_SDK_ROOT/cmdline-tools"
             mv "$ANDROID_SDK_ROOT/cmdline-tools/cmdline-tools" "$ANDROID_SDK_ROOT/cmdline-tools/latest"
@@ -47,6 +53,39 @@ jobs:
             "platforms;android-35" \
             "build-tools;35.0.0"
 
+      - name: Prepare optional release signing
+        if: github.event_name == 'release'
+        env:
+          ANDROID_KEYSTORE_BASE64: ${{ secrets.ANDROID_KEYSTORE_BASE64 }}
+          ANDROID_KEYSTORE_PASSWORD: ${{ secrets.ANDROID_KEYSTORE_PASSWORD }}
+          ANDROID_KEY_ALIAS: ${{ secrets.ANDROID_KEY_ALIAS }}
+          ANDROID_KEY_PASSWORD: ${{ secrets.ANDROID_KEY_PASSWORD }}
+        shell: bash
+        run: |
+          set -euo pipefail
+          missing=()
+          for key in ANDROID_KEYSTORE_BASE64 ANDROID_KEYSTORE_PASSWORD ANDROID_KEY_ALIAS ANDROID_KEY_PASSWORD; do
+            if [ -z "${!key:-}" ]; then
+              missing+=("$key")
+            fi
+          done
+
+          if [ ${#missing[@]} -gt 0 ]; then
+            printf -v missing_csv '%s, ' "${missing[@]}"
+            missing_csv="${missing_csv%, }"
+            echo "::warning::Release signing secrets missing: ${missing_csv}. Building unsigned/default-signed release AAB."
+            exit 0
+          fi
+
+          mkdir -p .ci-secrets
+          printf '%s' "$ANDROID_KEYSTORE_BASE64" | base64 -d > .ci-secrets/release-keystore.jks
+          cat > keystore.properties <<EOF
+          storeFile=.ci-secrets/release-keystore.jks
+          storePassword=$ANDROID_KEYSTORE_PASSWORD
+          keyAlias=$ANDROID_KEY_ALIAS
+          keyPassword=$ANDROID_KEY_PASSWORD
+          EOF
+
       - name: Make Gradle wrapper executable
         run: chmod +x gradlew
 
@@ -82,10 +121,17 @@ jobs:
           path: app/build/outputs/apk/debug/*.apk
           if-no-files-found: error
 
-      - name: Upload release AAB
+      - name: Attach release AAB to Gitea release
         if: github.event_name == 'release'
-        uses: actions/upload-artifact@v3
-        with:
-          name: release-aab
-          path: app/build/outputs/bundle/release/*.aab
-          if-no-files-found: error
+        env:
+          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
+        shell: bash
+        run: |
+          set -euxo pipefail
+          release_id="$(python3 -c 'import json, os; print(json.load(open(os.environ["GITHUB_EVENT_PATH"], encoding="utf-8"))["release"]["id"])')"
+          aab="$(find app/build/outputs/bundle/release -name '*.aab' | head -n 1)"
+          curl --fail-with-body \
+            --request POST \
+            --header "Authorization: token ${GITEA_TOKEN}" \
+            --form "attachment=@${aab}" \
+            "${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}/releases/${release_id}/assets?name=$(basename "$aab")"

app/build.gradle.kts

@@ -1,9 +1,23 @@
+import java.util.Properties
+
 plugins {
     id("com.android.application")
     id("org.jetbrains.kotlin.android")
     id("org.jetbrains.kotlin.plugin.compose")
 }
 
+val keystorePropertiesFile = rootProject.file("keystore.properties")
+val keystoreProperties = Properties()
+if (keystorePropertiesFile.exists()) {
+    keystorePropertiesFile.inputStream().use { keystoreProperties.load(it) }
+}
+val hasReleaseSigning = listOf(
+    "storeFile",
+    "storePassword",
+    "keyAlias",
+    "keyPassword",
+).all { !keystoreProperties.getProperty(it).isNullOrBlank() }
+
 android {
     namespace = "solutions.tretter.esunandroid"
     compileSdk = 35
@@ -19,6 +33,17 @@ android {
         vectorDrawables.useSupportLibrary = true
     }
 
+    signingConfigs {
+        if (hasReleaseSigning) {
+            create("release") {
+                storeFile = file(keystoreProperties.getProperty("storeFile"))
+                storePassword = keystoreProperties.getProperty("storePassword")
+                keyAlias = keystoreProperties.getProperty("keyAlias")
+                keyPassword = keystoreProperties.getProperty("keyPassword")
+            }
+        }
+    }
+
     buildTypes {
         release {
             isMinifyEnabled = false
@@ -26,6 +51,9 @@ android {
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
             )
+            if (hasReleaseSigning) {
+                signingConfig = signingConfigs.getByName("release")
+            }
         }
     }