Merge pull request #267 from powersync-ja/refactor-connection-locks

Refactor connection locks

Author: simolus3

packages/powersync_core/lib/src/abort_controller.dart

@@ -14,6 +14,10 @@ class AbortController {
     return _abortRequested.future;
   }
 
+  Future<void> get onCompletion {
+    return _abortCompleter.future;
+  }
+
   /// Abort, and wait until aborting is complete.
   Future<void> abort() async {
     aborted = true;

packages/powersync_core/lib/src/database/active_instances.dart

@@ -18,14 +18,23 @@ final class ActiveDatabaseGroup {
 
   /// Use to prevent multiple connections from being opened concurrently
   final Mutex syncConnectMutex = Mutex();
+  final Mutex syncMutex;
+  final Mutex crudMutex;
+
   final String identifier;
 
-  ActiveDatabaseGroup._(this.identifier);
+  ActiveDatabaseGroup._(this.identifier)
+      : syncMutex = Mutex(identifier: '$identifier-sync'),
+        crudMutex = Mutex(identifier: '$identifier-crud');
 
-  void close() {
+  Future<void> close() async {
     if (--refCount == 0) {
       final removedGroup = _activeGroups.remove(identifier);
       assert(removedGroup == this);
+
+      await syncConnectMutex.close();
+      await syncMutex.close();
+      await crudMutex.close();
     }
   }