[Breaking] Improve request typing (#3)

* Infer type from given request

* Update changelog

* Update readme

* Add external integration tests

* Bump `0.2.0`

* Avoid minification

* Add additional event handler

Author: Matthiee

CHANGELOG.md

@@ -1,4 +1,8 @@
-## 0.1.1 - 2023-12-22
+## 0.2.0
+
+- `RequestManager.send` now only accepts a single generic argument, `TResponse`, which is the type of the response body. The `TRequest` type argument has been removed. The type of the Response will be inferred based on the given `Request<Response>` (#3)
+
+## 0.1.1
 
 - Add `registerFactory` and `registerFunction` methods to `RequestManager`.
 

README.md

@@ -60,8 +60,7 @@ Future<void> main() async {
 
   mediator.requests.register(MyQueryHandler());
 
-  final response = await mediator.requests
-    .send<Something, MyQuery>(MyQuery());
+  final Something response = await mediator.requests.send(MyQuery());
 
   print(response);
 }

example/example.dart

@@ -20,25 +20,28 @@ Future<void> main() async {
       .map((event) => event.count)
       .distinct()
       .subscribeFunction(
-        (count) => print('[$CountEvent handler] received count: $count'),
+        (count) => print('[CountEvent handler] received count: $count'),
+      );
+
+  mediator.events.on<CountEvent>().subscribeFunction(
+        (count) => print('[Other Event Handler] received: $count'),
       );
 
   const getUserQuery = GetUserByIdQuery(123);
 
   print('Sending $getUserQuery request');
 
-  final resp =
-      await mediator.requests.send<User, GetUserByIdQuery>(getUserQuery);
+  final resp = await mediator.requests.send(getUserQuery);
 
-  print('Got $GetUserByIdQuery response: $resp');
+  print('Got $getUserQuery response: $resp');
 
   print('---');
 
   const order66Command = MyCommand('Order 66');
 
   print('Sending command $order66Command');
 
-  await mediator.requests.send<void, MyCommand>(order66Command);
+  await mediator.requests.send(order66Command);
 
   print('Command $order66Command completed');
 
@@ -58,23 +61,23 @@ class CountEvent implements DomainEvent {
   const CountEvent(this.count);
 
   @override
-  String toString() => '$CountEvent(count: $count)';
+  String toString() => 'CountEvent(count: $count)';
 }
 
 class MyCommand implements Command {
   final String command;
   const MyCommand(this.command);
 
   @override
-  String toString() => '$MyCommand(command: $command)';
+  String toString() => 'MyCommand(command: $command)';
 }
 
 class MyCommandHandler implements CommandHandler<MyCommand> {
   @override
   Future<void> handle(MyCommand request) async {
-    print('[$MyCommandHandler] Executing "$request"');
+    print('[MyCommandHandler] Executing "$request"');
     await Future.delayed(const Duration(milliseconds: 500));
-    print('[$MyCommandHandler] "$request" completed');
+    print('[MyCommandHandler] "$request" completed');
   }
 }
 
@@ -83,15 +86,15 @@ class GetUserByIdQuery implements Query<User> {
   const GetUserByIdQuery(this.userId);
 
   @override
-  String toString() => '$GetUserByIdQuery(userId: $userId)';
+  String toString() => 'GetUserByIdQuery(userId: $userId)';
 }
 
 class GetUserByIdQueryHandler implements QueryHandler<User, GetUserByIdQuery> {
   @override
   Future<User> handle(GetUserByIdQuery request) async {
-    print('[$GetUserByIdQueryHandler] handeling $request');
+    print('[GetUserByIdQueryHandler] handeling $request');
     final user = await getUserByIdAsync(request.userId);
-    print('[$GetUserByIdQueryHandler] got $user');
+    print('[GetUserByIdQueryHandler] got $user');
     return user;
   }
 }
@@ -100,10 +103,10 @@ class LoggingBehavior implements PipelineBehavior {
   @override
   Future handle(request, RequestHandlerDelegate next) async {
     try {
-      print('[$LoggingBehavior] [${request.runtimeType}] Before');
+      print('[LoggingBehavior] [$request] Before');
       return await next();
     } finally {
-      print('[$LoggingBehavior] [${request.runtimeType}] After');
+      print('[LoggingBehavior] [$request] After');
     }
   }
 }
@@ -115,7 +118,7 @@ class LoggingEventObserver implements EventObserver {
     Set<EventHandler<TEvent>> handlers,
   ) {
     print(
-      '[$LoggingEventObserver] onDispatch "$event" with ${handlers.length} handlers',
+      '[LoggingEventObserver] onDispatch "$event" with ${handlers.length} handlers',
     );
   }
 
@@ -126,7 +129,7 @@ class LoggingEventObserver implements EventObserver {
     Object error,
     StackTrace stackTrace,
   ) {
-    print('[$LoggingEventObserver] onError $event -> $handler ($error)');
+    print('[LoggingEventObserver] onError $event -> $handler ($error)');
   }
 
   @override
@@ -143,7 +146,7 @@ class User {
   const User(this.id, this.name);
 
   @override
-  String toString() => '$User(id: $id, name: $name)';
+  String toString() => 'User(id: $id, name: $name)';
 }
 
 Future<User> getUserByIdAsync(int id) async {

lib/src/request/handler/request_handler_store.dart

@@ -51,23 +51,26 @@ class RequestHandlerStore {
     _handlers.remove(TRequest);
   }
 
-  /// Returns the registered [RequestHandler]'s for [TRequest].
-  RequestHandler<TResponse, TRequest>
-      getHandlerFor<TResponse, TRequest extends Request<TResponse>>() {
-    final handler = _handlers[TRequest] ?? _handlerFactories[TRequest]?.call();
+  /// Returns the registered [RequestHandler]'s for [request].
+  RequestHandler getHandlerFor<TResponse extends Object?>(
+    Request<TResponse> request,
+  ) {
+    final requestType = request.runtimeType;
+    final handler =
+        _handlers[requestType] ?? _handlerFactories[requestType]?.call();
 
     assert(
       handler != null,
-      'getHandlerFor<$TResponse, $TRequest> did not have a registered handler. '
+      'getHandlerFor<$TResponse, $requestType> did not have a registered handler. '
       'Make sure to register the request handler first.',
     );
 
     assert(
-      handler is RequestHandler<TResponse, TRequest>,
+      handler is RequestHandler<TResponse, Request<TResponse>>,
       'The registered handler is of the wrong type got $handler but was '
-      'expecting a type of RequestHandler<$TResponse, $TRequest>',
+      'expecting a type of RequestHandler<$TResponse, $requestType>',
     );
 
-    return handler as RequestHandler<TResponse, TRequest>;
+    return handler!;
   }
 }

lib/src/request/pipeline/pipeline_behavior_store.dart

@@ -3,23 +3,34 @@ import 'package:dart_mediator/src/request/pipeline/pipeline_configurator.dart';
 import 'package:dart_mediator/src/request/pipeline/pipeline_behavior.dart';
 
 class PipelineBehaviorStore implements PipelineConfigurator {
-  final _handlers = <PipelineBehavior<Object?, Object>>{};
-  final _handlerFactories = <PipelineBehaviorFactory<Object?, Object>>{};
+  final _handlers = <Type, List<PipelineBehavior>>{};
+  final _handlerFactories = <Type, List<PipelineBehaviorFactory>>{};
   final _genericHandlers = <PipelineBehavior>{};
   final _genericHandlerFactories = <PipelineBehaviorFactory>{};
 
   @override
-  void register<TResponse extends Object?, TRequest extends Object>(
+  void register<TResponse extends Object?, TRequest extends Request<TResponse>>(
     PipelineBehavior<TResponse, TRequest> behavior,
   ) {
-    _handlers.add(behavior);
+    final handlers = _handlers.putIfAbsent(
+      TRequest,
+      () => <PipelineBehavior>[],
+    );
+
+    handlers.add(behavior);
   }
 
   @override
-  void registerFactory<TResponse extends Object?, TRequest extends Object>(
+  void registerFactory<TResponse extends Object?,
+      TRequest extends Request<TResponse>>(
     PipelineBehaviorFactory<TResponse, TRequest> factory,
   ) {
-    _handlerFactories.add(factory);
+    final handlers = _handlerFactories.putIfAbsent(
+      TRequest,
+      () => <PipelineBehaviorFactory>[],
+    );
+
+    handlers.add(factory);
   }
 
   @override
@@ -38,29 +49,37 @@ class PipelineBehaviorStore implements PipelineConfigurator {
 
   @override
   void unregister(PipelineBehavior behavior) {
-    _handlers.remove(behavior);
+    for (final handlers in _handlers.values) {
+      handlers.remove(behavior);
+    }
     _genericHandlers.remove(behavior);
   }
 
   @override
   void unregisterFactory(PipelineBehaviorFactory factory) {
-    _handlerFactories.remove(factory);
+    for (final handlers in _handlerFactories.values) {
+      handlers.remove(factory);
+    }
     _genericHandlerFactories.remove(factory);
   }
 
   /// Returns all [PipelineBehavior]'s that match.
-  List<PipelineBehavior> getPipelines<TResponse extends Object?,
-      TRequest extends Request<TResponse>>() {
-    final handlerFactories = _handlerFactories
-        .whereType<PipelineBehaviorFactory<TResponse, TRequest>>()
-        .map((factory) => factory());
+  List<PipelineBehavior> getPipelines(
+    Request request,
+  ) {
+    final requestType = request.runtimeType;
+
+    final handlerFactories =
+        _handlerFactories[requestType]?.map((factory) => factory());
 
     final genericFactories =
         _genericHandlerFactories.map((factory) => factory());
 
+    final handlers = _handlers[requestType];
+
     return [
-      ..._handlers.whereType<PipelineBehavior<TResponse, TRequest>>(),
-      ...handlerFactories,
+      if (handlers != null) ...handlers,
+      if (handlerFactories != null) ...handlerFactories,
       ..._genericHandlers,
       ...genericFactories,
     ];

lib/src/request/pipeline/pipeline_configurator.dart

@@ -1,4 +1,5 @@
 import 'package:dart_mediator/src/request/pipeline/pipeline_behavior.dart';
+import 'package:dart_mediator/src/request/request.dart';
 
 /// Factory to create a [PipelineBehavior].
 typedef PipelineBehaviorFactory<TRequest, TResponse>
@@ -9,15 +10,16 @@ abstract interface class PipelineConfigurator {
   ///
   /// When using a generic [PipelineBehavior] the [registerGeneric] should be
   /// used instead.
-  void register<TResponse extends Object?, TRequest extends Object>(
+  void register<TResponse extends Object?, TRequest extends Request<TResponse>>(
     PipelineBehavior<TResponse, TRequest> behavior,
   );
 
   /// Registers the [factory].
   ///
   /// When using a generic [PipelineBehavior] the [registerGenericFactory] should
   /// be used instead.
-  void registerFactory<TResponse extends Object?, TRequest extends Object>(
+  void registerFactory<TResponse extends Object?,
+      TRequest extends Request<TResponse>>(
     PipelineBehaviorFactory<TResponse, TRequest> factory,
   );
 

lib/src/request/request_manager.dart

@@ -57,14 +57,13 @@ class RequestManager {
   /// This request can be wrapped by [PipelineBehavior]'s see [pipeline].
   ///
   /// This will return [TResponse].
-  Future<TResponse>
-      send<TResponse extends Object?, TRequest extends Request<TResponse>>(
-    TRequest request,
+  Future<TResponse> send<TResponse extends Object?>(
+    Request<TResponse> request,
   ) async {
-    final handler = _requestHandlerStore.getHandlerFor<TResponse, TRequest>();
+    final handler = _requestHandlerStore.getHandlerFor(request)
+        as RequestHandler<TResponse, Request<TResponse>>;
 
-    final pipelines =
-        _pipelineBehaviorStore.getPipelines<TResponse, TRequest>();
+    final pipelines = _pipelineBehaviorStore.getPipelines(request);
 
     FutureOr<TResponse> handle() => handler.handle(request);
 
@@ -73,11 +72,13 @@ class RequestManager {
       (next, pipeline) => () => pipeline.handle(request, next),
     );
 
-    final response = await executionPlan();
+    final futureOrResult = executionPlan();
+    final response =
+        futureOrResult is Future ? await futureOrResult : futureOrResult;
 
     assert(
       response is TResponse,
-      '$TRequest expected a return type of $TResponse but '
+      '$request expected a return type of $TResponse but '
       'got one of type ${response.runtimeType}. '
       'One of the registered pipelines is not correctly returning the '
       '`next()` call. Pipelines used: $pipelines',

pubspec.yaml

@@ -2,7 +2,7 @@ name: dart_mediator
 description: >
   A simple yet highly configurable Mediator implementation
   that allows sending requests and publishing events.
-version: 0.1.1
+version: 0.2.0
 repository: https://github.com/MatthiWare/mediator.dart
 
 environment:

test/integration/choreography_test.dart

@@ -44,8 +44,7 @@ void main() {
           ),
         );
 
-        final stock = await mediator.requests
-            .send<Map<String, int>, GetInventoryQuery>(GetInventoryQuery());
+        final stock = await mediator.requests.send(GetInventoryQuery());
 
         expect(stock, {
           'mouse': 8,