I have a mail reading service that reads every email from an inbox, parses it and inserts it into a database. The issue I'm running into is that there is no guarantee that I will be parsing the emails in order they were received (this is a business requirement). My fix for this would be to introduce some sort of queueing system. This way I would process the items in order they came in. This would also give me the benefit of decoupling my reading of the emails and parsing/inserting them in the database.
So my question is is it overkill to use a service bus (such as NServiceBus) if I only plan on sending messages locally? Meaning that the service that would be reading emails and the service that parses/inserts emails in the database would reside on the same machine.
Thank you.
Yes, this is clearly overkill, especially since NServiceBus doesn't guarantee that messages are delivered in order.
You can just use a Queue<T>, assuming you know how to get the messages out in order (this appears to be where you are having trouble, not that you are or aren't using a queue or whatever; you have to know how to get the items into the queue in the right order to begin with).
KISS and YAGNI apply here, all day, every day.