fix: make integration installation atomic

.changeset/calm-guards-install.md

@@ -0,0 +1,6 @@
+---
+'posthog': patch
+'posthog-android': patch
+---
+
+Prevent duplicate integration installation during concurrent SDK setup.

posthog-android/src/main/java/com/posthog/android/internal/PostHogActivityLifecycleCallbackIntegration.kt

@@ -7,6 +7,7 @@ import android.os.Bundle
 import com.posthog.PostHogIntegration
 import com.posthog.PostHogInterface
 import com.posthog.android.PostHogAndroidConfig
+import java.util.concurrent.atomic.AtomicBoolean
 
 /**
  * Captures deep link and screen view events
@@ -18,10 +19,10 @@ internal class PostHogActivityLifecycleCallbackIntegration(
     private val config: PostHogAndroidConfig,
 ) : ActivityLifecycleCallbacks, PostHogIntegration {
     private var postHog: PostHogInterface? = null
+    private var ownsInstallation = false
 
     private companion object {
-        @Volatile
-        private var integrationInstalled = false
+        private val integrationInstalled = AtomicBoolean(false)
     }
 
     override fun onActivityCreated(
@@ -83,19 +84,28 @@ internal class PostHogActivityLifecycleCallbackIntegration(
     override fun onActivityDestroyed(activity: Activity) {
     }
 
+    @Synchronized
     override fun install(postHog: PostHogInterface) {
-        if (integrationInstalled) {
+        if (!integrationInstalled.compareAndSet(false, true)) {
             return
         }
-        integrationInstalled = true
+        ownsInstallation = true
 
         this.postHog = postHog
         application.registerActivityLifecycleCallbacks(this)
     }
 
+    @Synchronized
     override fun uninstall() {
-        this.postHog = null
-        integrationInstalled = false
-        application.unregisterActivityLifecycleCallbacks(this)
+        if (!ownsInstallation) {
+            return
+        }
+        try {
+            this.postHog = null
+            application.unregisterActivityLifecycleCallbacks(this)
+        } finally {
+            ownsInstallation = false
+            integrationInstalled.set(false)
+        }
     }
 }

posthog-android/src/main/java/com/posthog/android/internal/PostHogAppInstallIntegration.kt

@@ -6,6 +6,7 @@ import com.posthog.PostHogInterface
 import com.posthog.android.PostHogAndroidConfig
 import com.posthog.internal.PostHogPreferences.Companion.BUILD
 import com.posthog.internal.PostHogPreferences.Companion.VERSION
+import java.util.concurrent.atomic.AtomicBoolean
 
 /**
  * Captures app installed and updated events
@@ -16,23 +17,25 @@ internal class PostHogAppInstallIntegration(
     private val context: Context,
     private val config: PostHogAndroidConfig,
 ) : PostHogIntegration {
+    private var ownsInstallation = false
+
     private companion object {
-        @Volatile
-        private var integrationInstalled = false
+        private val integrationInstalled = AtomicBoolean(false)
     }
 
+    @Synchronized
     override fun install(postHog: PostHogInterface) {
-        if (integrationInstalled) {
-            return
-        }
         // While the store is unreadable (Direct Boot) VERSION/BUILD read as absent, which would
         // fire a spurious "Application Installed" for an existing install and overwrite the
         // persisted previous build on unlock. Stay uninstalled so the correct event can still be
         // emitted once the store is readable.
         if (config.cachePreferences?.isAvailable() == false) {
             return
         }
-        integrationInstalled = true
+        if (!integrationInstalled.compareAndSet(false, true)) {
+            return
+        }
+        ownsInstallation = true
 
         getPackageInfo(context, config)?.let { packageInfo ->
             config.cachePreferences?.let { preferences ->
@@ -74,7 +77,12 @@ internal class PostHogAppInstallIntegration(
         }
     }
 
+    @Synchronized
     override fun uninstall() {
-        integrationInstalled = false
+        if (!ownsInstallation) {
+            return
+        }
+        ownsInstallation = false
+        integrationInstalled.set(false)
     }
 }

posthog-android/src/main/java/com/posthog/android/internal/PostHogLifecycleObserverIntegration.kt

@@ -11,6 +11,7 @@ import com.posthog.android.PostHogAndroidConfig
 import com.posthog.internal.PostHogSessionManager
 import java.util.Timer
 import java.util.TimerTask
+import java.util.concurrent.atomic.AtomicBoolean
 
 /**
  * Captures app opened and backgrounded events
@@ -32,6 +33,7 @@ internal class PostHogLifecycleObserverIntegration(
     private val bgEndSessionDelayMs = (1000 * 60 * 30).toLong() // 30 minutes
 
     private var postHog: PostHogInterface? = null
+    private var ownsInstallation = false
 
     private companion object {
         // in case there are multiple instances or the SDK is closed/setup again
@@ -40,8 +42,7 @@ internal class PostHogLifecycleObserverIntegration(
         @Volatile
         private var fromBackground = false
 
-        @Volatile
-        private var integrationInstalled = false
+        private val integrationInstalled = AtomicBoolean(false)
     }
 
     override fun onStart(owner: LifecycleOwner) {
@@ -124,11 +125,12 @@ internal class PostHogLifecycleObserverIntegration(
         lifecycle.addObserver(this)
     }
 
+    @Synchronized
     override fun install(postHog: PostHogInterface) {
-        if (integrationInstalled) {
+        if (!integrationInstalled.compareAndSet(false, true)) {
             return
         }
-        integrationInstalled = true
+        ownsInstallation = true
 
         try {
             this.postHog = postHog
@@ -148,9 +150,12 @@ internal class PostHogLifecycleObserverIntegration(
         lifecycle.removeObserver(this)
     }
 
+    @Synchronized
     override fun uninstall() {
+        if (!ownsInstallation) {
+            return
+        }
         try {
-            integrationInstalled = false
             this.postHog = null
             if (isMainThread(mainHandler)) {
                 remove()
@@ -161,6 +166,9 @@ internal class PostHogLifecycleObserverIntegration(
             }
         } catch (e: Throwable) {
             config.logger.log("Failed to uninstall PostHogLifecycleObserverIntegration: $e")
+        } finally {
+            ownsInstallation = false
+            integrationInstalled.set(false)
         }
     }
 }

posthog-android/src/main/java/com/posthog/android/internal/PostHogTouchActivityIntegration.kt

@@ -10,6 +10,7 @@ import curtains.OnRootViewsChangedListener
 import curtains.TouchEventInterceptor
 import curtains.phoneWindow
 import curtains.touchEventInterceptors
+import java.util.concurrent.atomic.AtomicBoolean
 
 /**
  * Marks user touches as session activity by calling [PostHogSessionManager.touchSession]
@@ -22,9 +23,10 @@ import curtains.touchEventInterceptors
 internal class PostHogTouchActivityIntegration(
     private val config: PostHogAndroidConfig,
 ) : PostHogIntegration {
+    private var ownsInstallation = false
+
     private companion object {
-        @Volatile
-        private var integrationInstalled = false
+        private val integrationInstalled = AtomicBoolean(false)
     }
 
     private val touchInterceptor =
@@ -53,11 +55,12 @@ internal class PostHogTouchActivityIntegration(
             }
         }
 
+    @Synchronized
     override fun install(postHog: PostHogInterface) {
-        if (integrationInstalled || !isSupported()) {
+        if (!isSupported() || !integrationInstalled.compareAndSet(false, true)) {
             return
         }
-        integrationInstalled = true
+        ownsInstallation = true
         try {
             Curtains.rootViews.forEach { view ->
                 view.phoneWindow?.let { window ->
@@ -72,7 +75,11 @@ internal class PostHogTouchActivityIntegration(
         }
     }
 
+    @Synchronized
     override fun uninstall() {
+        if (!ownsInstallation) {
+            return
+        }
         try {
             Curtains.onRootViewsChangedListeners -= onRootViewsChangedListener
             Curtains.rootViews.forEach { view ->
@@ -83,7 +90,8 @@ internal class PostHogTouchActivityIntegration(
         } catch (e: Throwable) {
             config.logger.log("PostHogTouchActivityIntegration uninstall failed: $e.")
         } finally {
-            integrationInstalled = false
+            ownsInstallation = false
+            integrationInstalled.set(false)
         }
     }
 

posthog-android/src/main/java/com/posthog/android/replay/PostHogReplayIntegration.kt

@@ -101,6 +101,7 @@ import java.util.concurrent.CountDownLatch
 import java.util.concurrent.ExecutorService
 import java.util.concurrent.Executors
 import java.util.concurrent.TimeUnit
+import java.util.concurrent.atomic.AtomicBoolean
 
 public class PostHogReplayIntegration(
     private val context: Context,
@@ -191,6 +192,7 @@ public class PostHogReplayIntegration(
 
     private var postHog: PostHogInterface? = null
     private var replayQueue: PostHogReplayQueue? = null
+    private var ownsInstallation = false
 
     @Volatile
     private var replaySessionId: String? = null
@@ -524,11 +526,12 @@ public class PostHogReplayIntegration(
         decorViews.remove(view)
     }
 
+    @Synchronized
     override fun install(postHog: PostHogInterface) {
-        if (integrationInstalled || !isSupported()) {
+        if (!isSupported() || !integrationInstalled.compareAndSet(false, true)) {
             return
         }
-        integrationInstalled = true
+        ownsInstallation = true
         this.postHog = postHog
 
         // Wire up as buffer delegate for the replay queue
@@ -558,9 +561,12 @@ public class PostHogReplayIntegration(
         }
     }
 
+    @Synchronized
     override fun uninstall() {
+        if (!ownsInstallation) {
+            return
+        }
         try {
-            integrationInstalled = false
             this.postHog = null
 
             // Clear buffer delegate
@@ -589,6 +595,9 @@ public class PostHogReplayIntegration(
             decorViews.clear()
         } catch (e: Throwable) {
             config.logger.log("Session Replay uninstall failed: $e.")
+        } finally {
+            ownsInstallation = false
+            integrationInstalled.set(false)
         }
     }
 
@@ -2335,7 +2344,6 @@ public class PostHogReplayIntegration(
         const val ANDROID_COMPOSE_VIEW_CLASS_NAME: String = "androidx.compose.ui.platform.AndroidComposeView"
         const val ANDROID_COMPOSE_VIEW: String = "AndroidComposeView"
 
-        @Volatile
-        private var integrationInstalled = false
+        private val integrationInstalled = AtomicBoolean(false)
     }
 }

posthog-android/src/main/java/com/posthog/android/replay/internal/PostHogLogCatIntegration.kt

@@ -9,6 +9,7 @@ import com.posthog.internal.replay.RRPluginEvent
 import com.posthog.internal.replay.capture
 import java.text.SimpleDateFormat
 import java.util.Locale
+import java.util.concurrent.atomic.AtomicBoolean
 
 internal class PostHogLogCatIntegration(private val config: PostHogAndroidConfig) : PostHogIntegration {
     @Volatile
@@ -20,22 +21,23 @@ internal class PostHogLogCatIntegration(private val config: PostHogAndroidConfig
         get() = postHog?.isSessionReplayActive() ?: false
 
     private var postHog: PostHogInterface? = null
+    private var ownsInstallation = false
 
     private companion object {
-        @Volatile
-        private var integrationInstalled = false
+        private val integrationInstalled = AtomicBoolean(false)
     }
 
+    @Synchronized
     override fun install(postHog: PostHogInterface) {
         this.postHog = postHog
-        if (integrationInstalled) {
-            return
-        }
         val captureLogcat = config.remoteConfigHolder?.isConsoleLogRecordingEnabled() ?: true
         if (!config.sessionReplayConfig.captureLogcat || !captureLogcat) {
             return
         }
-        integrationInstalled = true
+        if (!integrationInstalled.compareAndSet(false, true)) {
+            return
+        }
+        ownsInstallation = true
         val cmd = mutableListOf("logcat", "-v", "threadtime", "*:E")
         val sdf = SimpleDateFormat("MM-dd HH:mm:ss.mmm", Locale.ROOT)
         cmd.add("-T")
@@ -107,11 +109,19 @@ internal class PostHogLogCatIntegration(private val config: PostHogAndroidConfig
     }
 
     @PostHogVisibleForTesting
-    internal fun isInstalled(): Boolean = integrationInstalled
+    internal fun isInstalled(): Boolean = integrationInstalled.get()
 
+    @Synchronized
     override fun uninstall() {
-        integrationInstalled = false
-        logcatInProgress = false
-        logcatThread?.interruptSafely()
+        if (!ownsInstallation) {
+            return
+        }
+        try {
+            logcatInProgress = false
+            logcatThread?.interruptSafely()
+        } finally {
+            ownsInstallation = false
+            integrationInstalled.set(false)
+        }
     }
 }