public static IServiceCollection AddQuery <TQuery, TResult, TQueryHandler>(this IServiceCollection source)
where TQuery : IQuery <TResult>
where TQueryHandler : class, IQueryHandler <TQuery, TResult>
{
AssertArguments.NotNull(source, nameof(source));
return(source.AddScoped <IQueryHandler <TQuery, TResult>, TQueryHandler>());
}
public virtual async Task <PaginatedResult <TResult> > ExecuteAsync(TQuery query)
{
AssertArguments.NotNull(query, nameof(query));
var unfilteredQuery = ExecuteCore(query);
var filteredQuery = unfilteredQuery
.Skip(query.Skip)
.Take(query.Limit);
return(new PaginatedResult <TResult>(
query.Skip,
query.Limit,
await unfilteredQuery.CountAsync(),
await filteredQuery.ToArrayAsync()
));
}
public virtual async Task <TResult> ProcessAsync <TResult>(IQuery <TResult> query)
{
AssertArguments.NotNull(query, nameof(query));
// finding the query handler by using query type. we will
// throw argument exception when no handler registered for
// specified query type.
var handlerType = typeof(IQueryHandler <,>).MakeGenericType(query.GetType(), typeof(TResult));
// TODO: using service provider to resolve query handler dependencies.
var handler = ServiceProvider.GetService(handlerType) as IQueryHandler <TResult>;
AssertArguments.IsTrue(
handler != null,
$"'{handlerType.Name}' is not a valid query handler type.",
"query"
);
return(await handler.ExecuteAsync(query));
}
public BookingQueryHandler(DreamlinesContext dbContext)
{
AssertArguments.NotNull(dbContext, nameof(dbContext));
Context = dbContext;
}
public DefaultQueryProcessor(IServiceProvider serviceProvider)
{
AssertArguments.NotNull(serviceProvider, nameof(serviceProvider));
ServiceProvider = serviceProvider;
}
public SalesUnitQueryHandler(DreamlinesContext context)
{
AssertArguments.NotNull(context, nameof(context));
Context = context;
}