public static IServiceCollection AddRequestProcessor(this IServiceCollection serviceCollection,
params Assembly[] assemblies)
{
var types = assemblies.SelectMany(x => x.GetTypes()).ToArray();
var cache = new RequestHandlerTypeCache();
var handlerInterfaceTypes = new[] { typeof(IRequestHandler <>), typeof(IRequestHandler <,>) };
foreach (var type in types)
{
var interfaces = type.GetInterfaces();
var handlerTypes = interfaces
.Where(@interface => @interface.IsGenericType)
.Where(@interface => handlerInterfaceTypes.Any(x => x == @interface.GetGenericTypeDefinition()))
.ToList();
if (handlerTypes.Count == 0)
{
continue;
}
if (handlerTypes.Count > 1)
{
throw new MSFrameworkException($"{type.FullName} should impl one handler");
}
var handlerType = handlerTypes.First();
var requestType = handlerType.GenericTypeArguments.First();
var method = type.GetMethods()
.FirstOrDefault(x =>
x.Name == "HandleAsync" &&
x.GetParameters().Length == 2 &&
x.GetParameters()[0].ParameterType == requestType &&
x.GetParameters()[1].ParameterType == typeof(CancellationToken));
if (method == null)
{
throw new MSFrameworkException("Can't find handler method");
}
if (cache.TryAdd(requestType, (type, method)))
{
serviceCollection.TryAddScoped(type);
}
else
{
throw new MSFrameworkException(
$"Register {requestType.FullName} with handler {type.FullName} failed");
}
}
serviceCollection.TryAddSingleton(cache);
serviceCollection.TryAddScoped <IRequestProcessor, DefaultRequestProcessor>();
return(serviceCollection);
}
public DefaultRequestProcessor(IServiceProvider serviceProvider)
{
_serviceProvider = serviceProvider;
_cache = _serviceProvider.GetRequiredService <RequestHandlerTypeCache>();
}
