dispatcher

dotnet/AipsCore/Application/Common/Dispatcher/Dispatcher.cs

@@ -0,0 +1,71 @@
+using AipsCore.Application.Abstract;
+using AipsCore.Application.Abstract.Command;
+using AipsCore.Application.Abstract.Query;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace AipsCore.Application.Common.Dispatcher;
+
+public sealed class Dispatcher : IDispatcher
+{
+    private readonly IServiceProvider _serviceProvider;
+
+    public Dispatcher(IServiceProvider serviceProvider)
+    {
+        _serviceProvider = serviceProvider;
+    }
+    
+    #region Execute
+
+    public async Task Execute(ICommand command, CancellationToken cancellationToken = default)
+    {
+        var handlerType = typeof(ICommandHandler<>).MakeGenericType(command.GetType());
+        
+        await this.Handle(handlerType, command, cancellationToken);
+    }
+
+    public async Task<TResult> Execute<TResult>(ICommand<TResult> command, CancellationToken cancellationToken = default)
+    {
+        var handlerType = typeof(ICommandHandler<,>).MakeGenericType(command.GetType(), typeof(TResult));
+        
+        return await this.HandleWithResult<TResult>(handlerType, command, cancellationToken);
+    }
+
+    public async Task<TResult> Execute<TResult>(IQuery<TResult> query, CancellationToken cancellationToken = default)
+    {
+        var handlerType = typeof(IQueryHandler<,>).MakeGenericType(query.GetType(), typeof(TResult));
+        
+        return await this.HandleWithResult<TResult>(handlerType, query, cancellationToken);
+    }
+    
+    #endregion
+
+    #region Handle
+    
+    private async Task Handle(Type handlerType, object commandOrQuery, CancellationToken cancellationToken = default)
+    {
+        dynamic handler = this.ResolveHandler(handlerType, commandOrQuery);
+        
+        await handler.Handle((dynamic)commandOrQuery, cancellationToken);
+    }
+    
+    private async Task<TResult> HandleWithResult<TResult>(Type handlerType, object commandOrQuery, CancellationToken cancellationToken = default)
+    {
+        dynamic handler = this.ResolveHandler(handlerType, commandOrQuery);
+        
+        return await handler.Handle((dynamic)commandOrQuery, cancellationToken);
+    }
+    
+    #endregion
+
+    private dynamic ResolveHandler(Type handlerType, object commandOrQuery)
+    {
+        dynamic? handler = _serviceProvider.GetService(handlerType);
+        
+        if (handler is null)
+        {
+            throw new DispatchException(commandOrQuery);
+        }
+
+        return handler;
+    }
+}