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Domain events and version control without CQRS

Hi I have the following script that I don’t understand how to get a possible sequence:

  • User 1 uses ui-based Task to change client name
  • Operation with application services in an aggregate
  • Aggregate fire event on the changed name changed
  • the bus sends a message using nservicebus
  • NServicebus Service
  • User 2 receives aggregate and call change address
  • Aggregate operation is called
  • Domain Event
  • Message on the bus
  • Bus reboot
  • Message 2 is selected first.
  • Processing message 2 and other restricted context updated with a new address
  • Message 1 is selected now, which is incorrect.
  • What is happening now

At 13 would there be an optimistic concurrency error if we pass the aggregate version in the event?

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Blair

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According to this , you should ask yourself:

What is the impact of business on failure?

In your current case, you have this problem once per million requests. I do not think that this would have a huge impact on the business if you accepted both requests as valid.

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