Unhandled Exception: Instance of 'ConnectionClosedException'

[heshaShawky]

Describe the bug

I am trying to make a bulk insertion on database using isolate, so based on docs did this but getting the following error

E/flutter ( 4398): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Instance of 'ConnectionClosedException'
E/flutter ( 4398): #0      DriftCommunication.request (package:drift/src/remote/communication.dart:113:66)
E/flutter ( 4398): #1      _RemoteQueryExecutor.ensureOpen (package:drift/src/remote/client_impl.dart:158:10)
E/flutter ( 4398): #2      Batch._commit (package:drift/src/runtime/api/batch.dart:190:26)
E/flutter ( 4398): #3      DatabaseConnectionUser.batch (package:drift/src/runtime/api/connection_user.dart:525:20)
E/flutter ( 4398): #4      CategoriesDAO.insertDefaultCategories.<anonymous closure> (package:mizaniti/src/database/dao/categories_dao.dart:123:18)
E/flutter ( 4398): #5      ComputeWithDriftIsolate.computeWithDatabase.<anonymous closure> (package:drift/isolate.dart:331:33)
E/flutter ( 4398): <asynchronous suspension>
E/flutter ( 4398): #6      _RemoteRunner._run (dart:isolate:1023:18)
E/flutter ( 4398): <asynchronous suspension>
E/flutter ( 4398): 
D/EGL_emulation( 4398): app_time_stats: avg=50.61ms min=3.25ms max=708.63ms count=20
D/ProfileInstaller( 4398): Installing profile for com.example.mizaniti

My code:

@DriftDatabase(
    tables: [SettingsTable, WalletsTable, TransactionsTable, CategoriesTable],
    daos: [SettingsDAO, WalletsDAO, TransactionsDAO, CategoriesDAO])
class AppDatabase extends _$AppDatabase {
  AppDatabase([QueryExecutor? executor]) : super(executor ?? _openConnection());

  @override
  int get schemaVersion => 1;

  @override
  MigrationStrategy get migration => MigrationStrategy(
        beforeOpen: (details) async {
          if (details.wasCreated) {
            // preloading settings
            await into(settingsTable).insert(
              SettingsData(
                id: 1,
                details: SettingsDetails.empty(),
              ),
            );

            CategoriesDAO.insertDefaultCategories(this);
          }
        },
      );
}

LazyDatabase _openConnection() {
  // the LazyDatabase util lets us find the right location for the file async.
  return LazyDatabase(() async {
    // put the database file, called db.sqlite here, into the documents folder
    // for your app.
    final dbFolder = await getApplicationDocumentsDirectory();
    final file = File(p.join(dbFolder.path, 'db.sqlite'));
    return NativeDatabase.createInBackground(file, logStatements: true);
  });
}

@lazySingleton
@DriftAccessor(tables: [CategoriesTable])
class CategoriesDAO extends DatabaseAccessor<AppDatabase>
    with _$CategoriesDAOMixin {
  CategoriesDAO(AppDatabase attachedDatabase) : super(attachedDatabase);

  

  static Future<void> insertDefaultCategories(AppDatabase database) async {
    await database.computeWithDatabase(
      computation: (database) async {
        // Expensive computation that runs on its own isolate but talks to the
        // main database.

        final categories = categoryList;

        database.batch((batch) => batch.insertAll(
            database.categoriesTable, categories,
            mode: InsertMode.insertOrReplace));
      },
      connect: (connection) {
        // This function is responsible for creating a second instance of your
        // database class with a short-lived [connection].
        // For this to work, your database class needs to have a constructor that
        // allows taking a connection as described above.
        return AppDatabase(connection);
      },
    );
  }
}

[simolus3]

The connection gets closed after the callback completes, so you need to await the database.batch call in insertDefaultCategories.