Proper api to terminate a MoorIsolate

moor/lib/src/runtime/isolate/communication.dart

@@ -1,6 +1,8 @@
 import 'dart:async';
 import 'dart:isolate';
 
+import 'package:pedantic/pedantic.dart';
+
 /// An isolate communication setup where there's a single "server" isolate that
 /// communicates with a varying amount of "client" isolates.
 ///
@@ -46,7 +48,12 @@ class IsolateCommunication {
 
     final response = (await stream.first) as _ServerConnectionResponse;
 
-    return IsolateCommunication._(response.sendPort, stream, debugLog);
+    final communication =
+        IsolateCommunication._(response.sendPort, stream, debugLog);
+
+    unawaited(communication.closed.then((_) => clientReceive.close()));
+
+    return communication;
   }
 
   /// Closes the connection to the server.
@@ -183,6 +190,10 @@ class Server {
   void close() {
     _openConnectionPort.close();
     _opened.close();
+
+    for (var connected in currentChannels) {
+      connected.close();
+    }
   }
 
   void _handleMessageOnConnectionPort(dynamic message) {
@@ -199,6 +210,7 @@ class Server {
 
       communication.closed.whenComplete(() {
         currentChannels.remove(communication);
+        receiveFromClient.close();
       });
     }
   }

moor/lib/src/runtime/isolate/moor_isolate.dart

@@ -3,6 +3,7 @@ import 'dart:isolate';
 
 import 'package:moor/moor.dart';
 import 'package:moor/src/runtime/executor/stream_queries.dart';
+import 'package:pedantic/pedantic.dart';
 import 'communication.dart';
 
 part 'client.dart';
@@ -33,9 +34,7 @@ class MoorIsolate {
   /// Identifier for the server isolate that we can connect to.
   final ServerKey _server;
 
-  final Isolate _isolate;
-
-  MoorIsolate._(this._server, this._isolate);
+  MoorIsolate._(this._server);
 
   /// Connects to this [MoorIsolate] from another isolate. All operations on the
   /// returned [DatabaseConnection] will be executed on a background isolate.
@@ -45,6 +44,21 @@ class MoorIsolate {
     return client._connection;
   }
 
+  /// Stops the background isolate and disconnects all [DatabaseConnection]s
+  /// created.
+  /// If you only want to disconnect a database connection created via
+  /// [connect], use [GeneratedDatabase.close] instead.
+  Future<void> shutdownAll() async {
+    final connection = await IsolateCommunication.connectAsClient(_server);
+    unawaited(connection.request(_NoArgsRequest.terminateAll).then((_) {},
+        onError: (_) {
+      // the background isolate is closed before it gets a chance to reply
+      // to the terminateAll request. Ignore the error
+    }));
+
+    await connection.closed;
+  }
+
   /// Creates a new [MoorIsolate] on a background thread.
   ///
   /// The [opener] function will be used to open the [DatabaseConnection] used
@@ -58,10 +72,9 @@ class MoorIsolate {
     final receiveServer = ReceivePort();
     final keyFuture = receiveServer.first;
 
-    final isolate = await Isolate.spawn(
-        _startMoorIsolate, [receiveServer.sendPort, opener]);
+    await Isolate.spawn(_startMoorIsolate, [receiveServer.sendPort, opener]);
     final key = await keyFuture as ServerKey;
-    return MoorIsolate._(key, isolate);
+    return MoorIsolate._(key);
   }
 
   /// Creates a [MoorIsolate] in the [Isolate.current] isolate. The returned
@@ -70,7 +83,7 @@ class MoorIsolate {
   /// connection which operations are all executed on this isolate.
   static MoorIsolate inCurrent(DatabaseOpener opener) {
     final server = _MoorServer(opener);
-    return MoorIsolate._(server.key, Isolate.current);
+    return MoorIsolate._(server.key);
   }
 }
 

moor/lib/src/runtime/isolate/protocol.dart

@@ -18,6 +18,10 @@ enum _NoArgsRequest {
   /// integer, which serves as an identifier for the transaction in
   /// [_ExecuteQuery.transactionId].
   startTransaction,
+
+  /// Close the background isolate, disconnect all clients, release all
+  /// associated resources
+  terminateAll,
 }
 
 enum _StatementMethod {

moor/lib/src/runtime/isolate/server.dart

@@ -37,6 +37,10 @@ class _MoorServer {
           return connection.executor.ensureOpen();
         case _NoArgsRequest.startTransaction:
           return _spawnTransaction();
+        case _NoArgsRequest.terminateAll:
+          server.close();
+          Isolate.current.kill();
+          break;
         // the following are requests which are handled on the client side
         case _NoArgsRequest.runOnCreate:
           throw UnsupportedError(

moor/test/isolate_test.dart

@@ -11,12 +11,12 @@ void main() {
 
   setUp(() async {
     isolate = await MoorIsolate.spawn(_backgroundConnection);
-    isolateConnection = await isolate.connect(isolateDebugLog: true);
+    isolateConnection = await isolate.connect(isolateDebugLog: false);
   });
 
   tearDown(() {
     isolateConnection.executor.close();
-    isolate.kill();
+    return isolate.shutdownAll();
   });
 
   test('can open database and send requests', () async {