fix: keep WorkManager InputMerger for R8 (AGP 9); minified demo + CI (#2589)

Co-authored-by: AR Abdul Azeez <abdul@onesignal.com>

Author: abdulraqeeb33

.github/workflows/ci.yml

@@ -7,6 +7,11 @@ concurrency:
 on:
   pull_request:
     branches: ["**"]
+  push:
+    branches:
+      - main
+      - "*-main"
+  workflow_dispatch:
 
 env:
   DIFF_COVERAGE_THRESHOLD: "80"
@@ -36,8 +41,13 @@ jobs:
         working-directory: OneSignalSDK
         run: |
           ./gradlew testDebugUnitTest --console=plain --continue
+      - name: "[Build] Demo app (minified release)"
+        working-directory: OneSignalSDK
+        run: |
+          ./gradlew :app:assembleGmsRelease --console=plain
       - name: "[Diff Coverage] Check for bypass"
         id: coverage_bypass
+        if: github.event_name == 'pull_request' || github.event_name == 'workflow_dispatch'
         run: |
           # Check if PR has Skip Coverage Check label
           if [ "${{ github.event_name }}" = "pull_request" ]; then
@@ -54,6 +64,7 @@ jobs:
             echo "bypass=false" >> $GITHUB_OUTPUT
           fi
       - name: "[Diff Coverage] Check coverage"
+        if: github.event_name == 'pull_request' || github.event_name == 'workflow_dispatch'
         working-directory: OneSignalSDK
         run: |
           # Use the shared coverage check script for consistency

.github/workflows/publish-release.yml

@@ -89,6 +89,10 @@ jobs:
         run: ./gradlew assembleRelease
         working-directory: OneSignalSDK
 
+      - name: Build minified demo app (validates R8 / consumer ProGuard rules)
+        run: ./gradlew :app:assembleGmsRelease --console=plain
+        working-directory: OneSignalSDK
+
       - name: Dry Run - Publish to Maven Local with signing
         working-directory: OneSignalSDK
         run: |

OneSignalSDK/onesignal/notifications/consumer-rules.pro

@@ -59,4 +59,14 @@
 # Keep OneSignal WorkManager workers and constructors used for runtime instantiation.
 -keep class com.onesignal.notifications.internal.** extends androidx.work.ListenableWorker {
     public <init>(android.content.Context, androidx.work.WorkerParameters);
-}
+}
+
+# WorkManager instantiates InputMerger classes via reflection (InputMerger.fromClassName).
+# R8 full mode (AGP 8+) strips no-arg constructors, causing:
+# java.lang.NoSuchMethodException: androidx.work.OverwritingInputMerger.<init>()
+# WM-WorkerWrapper E Could not create Input Merger androidx.work.OverwritingInputMerger
+# Keep all InputMerger subclasses (OverwritingInputMerger, ArrayCreatingInputMerger, etc.)
+-keep class * extends androidx.work.InputMerger {
+    public <init>();
+}
+

examples/demo/app/build.gradle.kts

@@ -53,7 +53,11 @@ android {
 
     buildTypes {
         release {
-            isMinifyEnabled = false
+            // Minify MUST be enabled to exercise R8 and validate WorkManager/ProGuard rules.
+            // See: SDK-4185, https://github.com/OneSignal/OneSignal-Android-SDK/issues/2582
+            isMinifyEnabled = true
+            isShrinkResources = true
+            signingConfig = signingConfigs.getByName("debug")
             proguardFiles(
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
@@ -66,7 +70,8 @@ android {
             initWith(getByName("release"))
             isDebuggable = false
             isProfileable = true
-            isMinifyEnabled = false
+            isMinifyEnabled = true
+            isShrinkResources = true
             signingConfig = signingConfigs.getByName("debug")
             matchingFallbacks += listOf("release")
         }

examples/demo/app/proguard-rules.pro

@@ -19,3 +19,8 @@
 # If you keep the line number information, uncomment this to
 # hide the original source file name.
 #-renamesourcefileattribute SourceFile
+
+# Demo-only suppression for optional OTel transitive classes.
+-dontwarn com.fasterxml.jackson.core.JsonFactory
+-dontwarn com.fasterxml.jackson.core.JsonGenerator
+-dontwarn com.google.auto.value.AutoValue$CopyAnnotations