private void ProcessCommand(ProcessingCommand processingCommand, ICommandAsyncHandlerProxy commandAsyncHandler, int retryTimes)
{
var command = processingCommand.Message;
_ioHelper.TryAsyncActionRecursively("GetCommandAsync",
() => _commandStore.GetAsync(command.Id),
currentRetryTimes => ProcessCommand(processingCommand, commandAsyncHandler, currentRetryTimes),
result =>
{
var existingHandledCommand = result.Data;
if (existingHandledCommand != null)
{
if (existingHandledCommand.Message != null)
{
PublishMessageAsync(processingCommand, existingHandledCommand.Message, 0);
}
else
{
CompleteCommand(processingCommand, CommandStatus.Success, null, null);
}
return;
}
HandleCommandAsync(processingCommand, commandAsyncHandler, 0);
},
() => string.Format("[commandId:{0},commandType:{1}]", command.Id, command.GetType().Name),
errorMessage =>
{
_logger.Fatal(string.Format("Get command by id has unknown exception, the code should not be run to here, errorMessage: {0}", errorMessage));
},
retryTimes, true);
}
private void HandleAggregateDuplicatedCommandAsync(ProcessingCommand processingCommand, IAggregateRoot dirtyAggregateRoot, DomainEventStream eventStream, int retryTimes)
{
var command = processingCommand.Message;
_ioHelper.TryAsyncActionRecursively <AsyncTaskResult <HandledCommand> >("GetCommandAsync",
() => _commandStore.GetAsync(command.Id),
currentRetryTimes => HandleAggregateDuplicatedCommandAsync(processingCommand, dirtyAggregateRoot, eventStream, currentRetryTimes),
result =>
{
var existingHandledCommand = result.Data;
if (existingHandledCommand != null)
{
HandleExistingHandledAggregateAsync(processingCommand, dirtyAggregateRoot, eventStream, existingHandledCommand, 0);
}
else
{
//到这里，说明当前command想添加到commandStore中时，提示command重复，但是尝试从commandStore中取出该command时却找不到该command。
//出现这种情况，我们就无法再做后续处理了，这种错误理论上不会出现，除非commandStore的Add接口和Get接口出现读写不一致的情况；
//我们记录错误日志，然后认为当前command已被处理为失败。
var errorMessage = string.Format("Command exist in the command store, but we cannot get it from the command store. commandType:{0}, commandId:{1}",
command.GetType().Name,
command.Id);
NotifyCommandExecuted(processingCommand, CommandStatus.Failed, null, errorMessage);
}
},
() => string.Format("[commandId:{0}]", command.Id),
() => NotifyCommandExecuted(processingCommand, CommandStatus.Failed, null, "Get command async failed."),
retryTimes);
}
private void ProcessCommand(ProcessingCommand processingCommand, ICommandAsyncHandlerProxy commandAsyncHandler, int retryTimes)
{
var command = processingCommand.Message;
_ioHelper.TryAsyncActionRecursively <AsyncTaskResult <HandledCommand> >("GetCommandAsync",
() => _commandStore.GetAsync(command.Id),
currentRetryTimes => ProcessCommand(processingCommand, commandAsyncHandler, currentRetryTimes),
result =>
{
var existingHandledCommand = result.Data;
if (existingHandledCommand != null)
{
NotifyCommandExecuted(processingCommand, CommandStatus.NothingChanged, null, null);
return;
}
if (_logger.IsDebugEnabled)
{
_logger.DebugFormat("Duplicate command execution, commandId:{0},commandType:{1}", command.Id, command.GetType().Name);
}
HandleCommandAsync(processingCommand, commandAsyncHandler, 0);
},
() => string.Format("[commandId:{0},commandType:{1}]", command.Id, command.GetType().Name),
errorMessage => NotifyCommandExecuted(processingCommand, CommandStatus.Failed, typeof(string).FullName, errorMessage ?? "Get command async failed."),
retryTimes);
}
