We've now got some publishers put together inside of our order service.
And at this point time I'm really excited because we've got publishers available inside the order service
and inside the ticket service.
So here's what we're going to start to work on.
We're going to start to put together some number of listeners in these two services.
Remember that the goal of a listener is to process a number of incoming events inside of both these
services.
We have to create two different listeners.
So you might recall seeing this diagram right here was a diagram of where all these different events
are coming from and where they're going to go for the ticket created event.
We need to make sure that the order service receives this event or it listens for ticket created.
And I've got some notes on here about what that listener needs to do the order service also needs to
listen for ticket updated.
That's two listeners at least we have to build inside order service then inside the ticket service.
We need to make sure that thing listens for the order created event and for the order canceled event.
We're going to first begin working on our listeners or creating a ticket and updating a ticket.
So these are both listeners we're going to put together inside of our orders service.
And the reason I'm so excited about this is that this is where we're going to start to see some crazy
concurrency issues start to come up and we're going to figure out how to solve these concurrency issues.
You might recall discussing this diagram a little bit ago a couple hours ago inside the course where
we discussed having some of these events of ticket created and ticket updated come into our application
in some weird order and we saw that if they get processed in a weird order we could end up with some
super invalid data.
So we eventually came up with a solution of using this version field to somehow track in order these
different events inside of our app.
So this is where we're going to start to go back to all this concurrency stuff and implement this versioning
thing.
So again the first stuff we're gonna put together we're going to get a listener put together or ticket
created and ticket updated inside of our order service.
And as soon as we do that so we're going to start to see these version numbers start to become really
important.
All right.
Now we got a little preview of what we're gonna be focusing on.
Let's take a quick pause right here.
We're going to get a quick reminder on how we create a listener in the next video.