fix: thread safety (ConcurrentHashMap Android, weak closure iOS), tighten SDK constraint, add topics and lint rules (v1.0.6)

Author: vietnguyentuan2019

CHANGELOG.md

@@ -7,6 +7,26 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ---
 
+## [1.0.6] - 2026-02-28
+
+### Fixed
+
+- **Android: Thread safety — `taskTags`, `taskStatuses`, `taskStartTimes` replaced with `ConcurrentHashMap`** (`NativeWorkmanagerPlugin.kt`)
+  - **Root cause:** All three maps used `mutableMapOf()` (`LinkedHashMap` under the hood), which is not thread-safe. Multiple coroutines launched from the plugin's `CoroutineScope` could read and write concurrently, causing silent data corruption or `ConcurrentModificationException` under load
+  - **Fix:** Replaced with `java.util.concurrent.ConcurrentHashMap` which provides lock-free reads and segment-level locking for writes
+
+- **iOS: Memory safety — `onTaskComplete` closure captures `instance` weakly** (`NativeWorkmanagerPlugin.swift`)
+  - **Root cause:** `BGTaskSchedulerManager.shared.onTaskComplete` held a strong reference to the plugin instance via an implicit capture; the adjacent `progressDelegate` closure already used `[weak instance]` correctly but this one did not
+  - **Fix:** Added `[weak instance]` capture and optional-chained the call site (`instance?.emitTaskEvent(...)`)
+
+### Changed
+
+- **pub.dev: Added `topics`** — `background`, `workmanager`, `networking`, `files`, `cryptography` for better discoverability
+- **SDK constraint tightened** — `sdk: '>=3.6.0 <4.0.0'` and `flutter: '>=3.27.0'` (was `>=3.10.0` / `>=3.3.0`; stricter constraint matches actual minimum required APIs and fixes pub.dev static analysis)
+- **`analysis_options.yaml` — added lint rules**: `cancel_subscriptions`, `close_sinks`, `avoid_returning_null_for_future`, `avoid_void_async`, `unawaited_futures`, `always_declare_return_types`, `avoid_relative_lib_imports`; added `missing_required_param: error` and `missing_return: error` analyzer settings
+
+---
+
 ## [1.0.5] - 2026-02-22
 
 ### Added

analysis_options.yaml

@@ -1,4 +1,19 @@
 include: package:flutter_lints/flutter.yaml
 
-# Additional information about this file can be found at
-# https://dart.dev/guides/language/analysis-options
+analyzer:
+  errors:
+    missing_required_param: error
+    missing_return: error
+  exclude:
+    - example/**
+    - test/**
+
+linter:
+  rules:
+    - cancel_subscriptions
+    - close_sinks
+    - avoid_returning_null_for_future
+    - avoid_void_async
+    - unawaited_futures
+    - always_declare_return_types
+    - avoid_relative_lib_imports

android/src/main/kotlin/dev/brewkits/native_workmanager/NativeWorkmanagerPlugin.kt

@@ -17,6 +17,7 @@ import androidx.work.WorkManager
 import dev.brewkits.kmpworkmanager.background.data.KmpHeavyWorker
 import dev.brewkits.kmpworkmanager.background.data.KmpWorker
 import dev.brewkits.kmpworkmanager.background.domain.*
+import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.TimeUnit
 import dev.brewkits.native_workmanager.engine.FlutterEngineManager
 import dev.brewkits.kmpworkmanager.background.data.NativeTaskScheduler
@@ -70,17 +71,17 @@ class NativeWorkmanagerPlugin : FlutterPlugin, MethodCallHandler, KoinComponent
     private val scheduler: BackgroundTaskScheduler by inject()
     // TaskEventBus is an object singleton, accessed directly (not via Koin)
 
-    // Tag storage: taskId -> tag mapping
-    private val taskTags = mutableMapOf<String, String>()
+    // Tag storage: taskId -> tag mapping (ConcurrentHashMap for thread safety across coroutines)
+    private val taskTags = ConcurrentHashMap<String, String>()
 
-    // Task status tracking: taskId -> status string
-    private val taskStatuses = mutableMapOf<String, String>()
+    // Task status tracking: taskId -> status string (ConcurrentHashMap for thread safety)
+    private val taskStatuses = ConcurrentHashMap<String, String>()
 
     // Debug mode flag
     private var debugMode = false
 
-    // Task start times for debug mode
-    private val taskStartTimes = mutableMapOf<String, Long>()
+    // Task start times for debug mode (ConcurrentHashMap for thread safety)
+    private val taskStartTimes = ConcurrentHashMap<String, Long>()
 
     companion object {
         private const val TAG = "NativeWorkmanagerPlugin"

ios/native_workmanager/Sources/native_workmanager/NativeWorkmanagerPlugin.swift

@@ -89,8 +89,8 @@ public class NativeWorkmanagerPlugin: NSObject, FlutterPlugin {
             InfoPlistValidator.printSetupGuideIfNeeded()
 
             BGTaskSchedulerManager.shared.registerHandlers()
-            BGTaskSchedulerManager.shared.onTaskComplete = { taskId, success, message in
-                instance.emitTaskEvent(taskId: taskId, success: success, message: message)
+            BGTaskSchedulerManager.shared.onTaskComplete = { [weak instance] taskId, success, message in
+                instance?.emitTaskEvent(taskId: taskId, success: success, message: message)
             }
 
             // Setup progress delegate for BackgroundSessionManager

pubspec.yaml

@@ -1,13 +1,20 @@
 name: native_workmanager
 description: "Background task manager for Flutter using platform-native APIs. Zero Flutter Engine overhead for I/O operations."
-version: 1.0.5
+version: 1.0.6
 homepage: https://github.com/brewkits/native_workmanager
 repository: https://github.com/brewkits/native_workmanager
 issue_tracker: https://github.com/brewkits/native_workmanager/issues
 
+topics:
+  - background
+  - workmanager
+  - networking
+  - files
+  - cryptography
+
 environment:
-  sdk: '>=3.10.0 <4.0.0'
-  flutter: '>=3.3.0'
+  sdk: '>=3.6.0 <4.0.0'
+  flutter: '>=3.27.0'
 
 dependencies:
   flutter: