chore: delete queue files if serialization fails

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## Next
 
 - feat: support reuse of `anonymousId` between user changes ([#229](https://github.com/PostHog/posthog-android/pull/229))
+- chore: delete queue files if serialization fails ([#232](https://github.com/PostHog/posthog-android/pull/232))
 
 ## 3.11.3 - 2025-02-26
 

posthog/src/main/java/com/posthog/internal/PostHogQueue.kt

@@ -81,16 +81,23 @@ internal class PostHogQueue(
                     deque.add(file)
                 }
 
+                var hasPendingEvents = true
                 try {
                     val os = config.encryption?.encrypt(file.outputStream()) ?: file.outputStream()
                     os.use { theOutputStream ->
                         config.serializer.serialize(event, theOutputStream.writer().buffered())
                     }
                     config.logger.log("Queued Event ${event.event}: ${file.name}.")
-
-                    flushIfOverThreshold()
                 } catch (e: Throwable) {
+                    hasPendingEvents = false
                     config.logger.log("Event ${event.event}: ${file.name} failed to parse: $e.")
+
+                    // if for some reason the file failed to serialize, lets delete it
+                    file.deleteSafely(config)
+                }
+
+                if (hasPendingEvents) {
+                    flushIfOverThreshold()
                 }
             }
         }
@@ -163,6 +170,17 @@ internal class PostHogQueue(
         }
     }
 
+    private fun deleteFileSafely(
+        file: File,
+        throwable: Throwable? = null,
+    ) {
+        synchronized(dequeLock) {
+            deque.remove(file)
+        }
+        file.deleteSafely(config)
+        config.logger.log("File: ${file.name} failed to parse: $throwable.")
+    }
+
     @Throws(PostHogApiError::class, IOException::class)
     private fun batchEvents() {
         val files = takeFiles()
@@ -175,14 +193,12 @@ internal class PostHogQueue(
                     val event = config.serializer.deserialize<PostHogEvent?>(it.reader().buffered())
                     event?.let { theEvent ->
                         events.add(theEvent)
+                    } ?: run {
+                        deleteFileSafely(file)
                     }
                 }
             } catch (e: Throwable) {
-                synchronized(dequeLock) {
-                    deque.remove(file)
-                }
-                file.deleteSafely(config)
-                config.logger.log("File: ${file.name} failed to parse: $e.")
+                deleteFileSafely(file, e)
             }
         }
 

posthog/src/main/java/com/posthog/internal/PostHogSendCachedEventsIntegration.kt

@@ -79,11 +79,12 @@ internal class PostHogSendCachedEventsIntegration(
                                 event?.let {
                                     events.add(event)
                                     eventsCount++
+                                } ?: run {
+                                    removeFileSafely(iterator)
                                 }
                             }
                         } catch (e: Throwable) {
-                            iterator.remove()
-                            config.logger.log("Event failed to parse: $e.")
+                            removeFileSafely(iterator, e)
                         }
                         // stop the while loop since the batch is full
                         if (events.size >= config.maxBatchSize) {
@@ -135,6 +136,24 @@ internal class PostHogSendCachedEventsIntegration(
         }
     }
 
+    private fun deleteFileSafely(
+        file: File,
+        iterator: MutableIterator<File>,
+        throwable: Throwable? = null,
+    ) {
+        config.logger.log("File: ${file.name} failed to parse: $throwable.")
+        iterator.remove()
+        file.deleteSafely(config)
+    }
+
+    private fun removeFileSafely(
+        iterator: MutableIterator<ByteArray>,
+        throwable: Throwable? = null,
+    ) {
+        config.logger.log("Event failed to parse: $throwable.")
+        iterator.remove()
+    }
+
     @Throws(PostHogApiError::class, IOException::class)
     private fun flushEvents(
         storagePrefix: String?,
@@ -175,12 +194,12 @@ internal class PostHogSendCachedEventsIntegration(
                                 event?.let {
                                     events.add(event)
                                     eventsCount++
+                                } ?: run {
+                                    deleteFileSafely(file, iterator)
                                 }
                             }
                         } catch (e: Throwable) {
-                            config.logger.log("File: ${file.name} failed to parse: $e.")
-                            iterator.remove()
-                            file.deleteSafely(config)
+                            deleteFileSafely(file, iterator, e)
                         }
 
                         // stop the while loop since the batch is full