c# - 如何使用 ASP.NET 样板实现多个通知程序？
问题描述
我正在使用 ASP.NET 样板（带有 .NET Core）。我正在尝试实现Multiple Notifiers下官方文档中提到的通知系统，但我遇到了：
System.NullReferenceException：“对象引用未设置为对象的实例。”
我的问题与异常本身无关。我想知道在实现示例之前是否有任何预请求配置或设置，或者我的代码是否遗漏了一些东西：
public class MessageAppService: AsyncCrudAppService<Message, MessageDto, long, PagedAndSortedResultRequestDto, CreateMessageDto, UpdateMessageDto, ReadMessageDto>, IRealTimeNotifier, ITransientDependency
{
private readonly IRepository<Message, long> _repository;
private readonly IDbContextProvider<MySystemDbContext> _dbContextProvider;
private MySystemDbContext db => _dbContextProvider.GetDbContext();
IHubContext<MyChatHub> _hubContext; // This for online chat
private readonly IEmailSender _emailSender;
private readonly UserManager _userManager;
private readonly INotificationSubscriptionManager _notificationSubscriptionManager;
public MessageAppService(
IDbContextProvider<MySystemDbContext> dbContextProvider,
IRepository<Message, long> repository,
IHubContext<MyChatHub> hubContext /* This for online chat */,
INotificationSubscriptionManager notificationSubscriptionManager,
IEmailSender emailSender,
UserManager userManager
) : base(repository)
{
_repository = repository;
_dbContextProvider = dbContextProvider;
_hubContext = hubContext; // This for online chat
_notificationSubscriptionManager = notificationSubscriptionManager;
_emailSender = emailSender;
_userManager = userManager;
}
public override async Task<MessageDto> CreateAsync(CreateMessageDto input)
{
var test = await base.CreateAsync(input);
UserNotification userNotifications = new UserNotification();
userNotifications.UserId = 10010;
//
userNotifications.Notification.TenantId = AbpSession.TenantId;
userNotifications.Notification.NotificationName = "test";
UserNotification[] notificationList = new UserNotification[1];
notificationList[0] = userNotifications;
await SendNotificationsAsync(notificationList);
return test;
}
public async Task SendNotificationsAsync(UserNotification[] userNotifications)
{
foreach (var userNotification in userNotifications)
{
if (userNotification.Notification.Data is MessageNotificationData data)
{
var user = await _userManager.GetUserByIdAsync(userNotification.UserId);
_emailSender.Send(
to: "testg@gmail.com",
subject: "You have a new notification!",
body: data.Message,
isBodyHtml: true
);
}
}
}
void IRealTimeNotifier.SendNotifications(UserNotification[] userNotifications)
{
throw new NotImplementedException();
}
}
我在 .Application 模块的 PreInitialize() 函数中添加了以下内容：
Configuration.Notifications.Notifiers.Add<MessageAppService>();
更新：
我知道如何避免这种异常，但我想知道我在代码中实现的步骤是否足以获得通知。
更新 2：
我已经在aaron提到的问题中应用了代码。我有另一个例外：
WARN 2020-07-05 13:30:06,907 [9 ] fications.DefaultNotificationDistributer - System.Net.Mail.SmtpException: Failure sending mail.
---> System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (10061): No connection could be made because the target machine actively refused it. [::ffff:127.0.0.1]:25
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.Sockets.Socket.Connect(EndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(IPEndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
--- End of stack trace from previous location where exception was thrown ---
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
--- End of inner exception stack trace ---
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Abp.Net.Mail.Smtp.SmtpEmailSender.SendEmail(MailMessage mail)
at Abp.Net.Mail.EmailSenderBase.Send(MailMessage mail, Boolean normalize)
at Abp.Net.Mail.EmailSenderBase.Send(String to, String subject, String body, Boolean isBodyHtml)
at MySystem.ChatAppService.MessageAppService.SendNotificationsAsync(UserNotification[] userNotifications) in D:\WorkSpace\MySystem\aspnet-core\src\MySystem.Application\ChatAppService\MessageAppService.cs:line 172
at Abp.Notifications.DefaultNotificationDistributer.NotifyAsync(UserNotification[] userNotifications)
System.Net.Mail.SmtpException: Failure sending mail.
---> System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (10061): No connection could be made because the target machine actively refused it. [::ffff:127.0.0.1]:25
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.Sockets.Socket.Connect(EndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(IPEndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
--- End of stack trace from previous location where exception was thrown ---
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
--- End of inner exception stack trace ---
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Abp.Net.Mail.Smtp.SmtpEmailSender.SendEmail(MailMessage mail)
at Abp.Net.Mail.EmailSenderBase.Send(MailMessage mail, Boolean normalize)
at Abp.Net.Mail.EmailSenderBase.Send(String to, String subject, String body, Boolean isBodyHtml)
at MySystem.ChatAppService.MessageAppService.SendNotificationsAsync(UserNotification[] userNotifications) in D:\WorkSpace\MySystem\aspnet-core\src\MySystem.Application\ChatAppService\MessageAppService.cs:line 172
at Abp.Notifications.DefaultNotificationDistributer.NotifyAsync(UserNotification[] userNotifications)
WARN 2020-07-05 13:30:09,049 [10 ] fications.DefaultNotificationDistributer - System.Net.Mail.SmtpException: Failure sending mail.
---> System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (10061): No connection could be made because the target machine actively refused it. [::ffff:127.0.0.1]:25
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.Sockets.Socket.Connect(EndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(IPEndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
--- End of stack trace from previous location where exception was thrown ---
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
--- End of inner exception stack trace ---
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Abp.Net.Mail.Smtp.SmtpEmailSender.SendEmail(MailMessage mail)
at Abp.Net.Mail.EmailSenderBase.Send(MailMessage mail, Boolean normalize)
at Abp.Net.Mail.EmailSenderBase.Send(String to, String subject, String body, Boolean isBodyHtml)
at MySystem.ChatAppService.MessageAppService.SendNotificationsAsync(UserNotification[] userNotifications) in D:\WorkSpace\MySystem\aspnet-core\src\MySystem.Application\ChatAppService\MessageAppService.cs:line 172
at Abp.Notifications.DefaultNotificationDistributer.NotifyAsync(UserNotification[] userNotifications)
System.Net.Mail.SmtpException: Failure sending mail.
---> System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (10061): No connection could be made because the target machine actively refused it. [::ffff:127.0.0.1]:25
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.Sockets.Socket.Connect(EndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(IPEndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
--- End of stack trace from previous location where exception was thrown ---
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
--- End of inner exception stack trace ---
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Abp.Net.Mail.Smtp.SmtpEmailSender.SendEmail(MailMessage mail)
at Abp.Net.Mail.EmailSenderBase.Send(MailMessage mail, Boolean normalize)
at Abp.Net.Mail.EmailSenderBase.Send(String to, String subject, String body, Boolean isBodyHtml)
at MySystem.ChatAppService.MessageAppService.SendNotificationsAsync(UserNotification[] userNotifications) in D:\WorkSpace\MySystem\aspnet-core\src\MySystem.Application\ChatAppService\MessageAppService.cs:line 172
at Abp.Notifications.DefaultNotificationDistributer.NotifyAsync(UserNotification[] userNotifications)
ERROR 2020-07-05 13:30:28,176 [10 ] Mvc.ExceptionHandling.AbpExceptionFilter - Failure sending mail.
System.Net.Mail.SmtpException: Failure sending mail.
---> System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (10061): No connection could be made because the target machine actively refused it. [::ffff:127.0.0.1]:25
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.Sockets.Socket.Connect(EndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(IPEndPoint remoteEP)
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
--- End of stack trace from previous location where exception was thrown ---
at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
--- End of inner exception stack trace ---
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Abp.Net.Mail.Smtp.SmtpEmailSender.SendEmail(MailMessage mail)
at Abp.Net.Mail.EmailSenderBase.Send(MailMessage mail, Boolean normalize)
at Abp.Net.Mail.EmailSenderBase.Send(String to, String subject, String body, Boolean isBodyHtml)
at MySystem.ChatAppService.MessageAppService.CreateAsync(CreateMessageDto input) in D:\WorkSpace\MySystem\aspnet-core\src\MySystem.Application\ChatAppService\MessageAppService.cs:line 153
at Abp.Authorization.AuthorizationInterceptor.InternalInterceptAsynchronous[TResult](IInvocation invocation)
at Abp.Domain.Uow.UnitOfWorkInterceptor.InternalInterceptAsynchronous[TResult](IInvocation invocation)
at Abp.Auditing.AuditingInterceptor.InternalInterceptAsynchronous[TResult](IInvocation invocation)
at Abp.Runtime.Validation.Interception.ValidationInterceptor.InternalInterceptAsynchronous[TResult](IInvocation invocation)
at lambda_method(Closure , Object )
at Microsoft.Extensions.Internal.ObjectMethodExecutorAwaitable.Awaiter.GetResult()
at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.AwaitableObjectResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeInnerFilterAsync>g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextExceptionFilterAsync>g__Awaited|25_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
解决方案
你没有向我们展示足够的信息。UserNotification类包含什么？这是你自己的类还是 ABP 框架的代码？
我看到的第一个明显错误是这段代码：
UserNotification userNotifications = new UserNotification();
userNotifications.UserId = 10010;
//
userNotifications.Notification.TenantId = AbpSession.TenantId;
userNotifications.Notification.NotificationName = "test";
该Notification属性似乎没有被初始化。我希望看到类似的东西：
UserNotification userNotification = new UserNotification
{
UserId = 10010,
Notification = new Notification
{
TenantId = AbpSession.TenantId,
NotificationName = "test"
}
};
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