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We've now got an initial implementation of our event plus but together we're not going to start to go

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through our Postal Service and our common service.

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Anytime something interesting happens inside those services such as creating a new post or creating

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a new comment we're gonna make sure that we send a request over to this events and point in our event

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bus and in that request we're going to include the event event plus we'll then take that event and echo

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it out to all the different services running inside of our application at present are different services

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do not have this post events and point wired up.

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So when the event bus tries to send that request over the request is going to fail due to a for a for

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as soon as we make sure that the event bus can emit this event will then go back over and start to implement

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these end points that the other services can listen to these events that are being emitted.

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But again right now we're just gonna make sure that the Postal Service is going to meet this event anytime

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someone creates a new post so let's get to it.

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Between the last video and this one I opened up my code editor inside of my roots blog project directory.

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We're going to start to have to change between all for these different services very quickly and so

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it's just a lot easier to maneuver between them if we have all of our projects open inside of one editor

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as opposed to four separate editors.

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I'm going to find the post directory inside there I'll find the next dot J File at the very top.

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I'll immediately require an axis like so and then going to scroll down to our post end point.

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So this is the code that gets executed every single time someone tries to create new post.

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So this would be a perfect time to try to emit an event saying hey someone just made a new post right

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after we add the new post to our post collection.

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I'll use axioms to make a post request over to age TTP.

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Colin flash flash local host in four thousand five.

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Because remember that is where a broker is running flash events

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and then as the second argument we'll put in the actual event that we want to send over.

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So for right now we'll say that every event that we met is going to have two properties.

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The first one is going to be a type and that type describes that event that just occurred the second

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property will be a data property and that will have some information that further clarifies exactly

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what happened in the case of creating a post we'll probably include the actual post that was just created

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as the data property.

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Remember that event that we send out throughout our application can have any structure we want.

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It doesn't have to be an object it can be a string or a number.

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Any data you want to have.

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But usually we're going to make sure that all these events have a very consistent structure.

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We'll talk more about the design and sort of schema of events quite a bit over time.

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Right now we're just gonna say that every event will have a type.

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And data gets us the object right here is essentially the event that I want to have emitted or my entire

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application going to give it a type of post created and then a data and data is going to be the post

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that we just made.

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I remember all of our posts have an I.D. and title.

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That's essentially what our post is.

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So we pretty much want to take that style of object right there included as the data property.

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We'll say I.D. and title then finally this is an asynchronous operation making the network request.

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So we will add on async and await like so that I'm going to say this we're gonna flip back over to our

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browser and find our running react application.

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I'm going to refresh this page and as soon as I do you'll notice that all the posts go away.

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That is totally fine it's because remember all of our posts are being stored in memory with that post

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service.

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So as soon as we restart that server all of our posts just disappear.

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All right I'll go ahead and try to create a post we'll call this new post and submit it.

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We don't have any kind of live reload on the react application so I have to refresh the page as soon

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as I do so I do see the new post appear.

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What happened to that event.

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Well let's go take a look at our terminal.

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We'll take a look at our server logs.

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We'll just make sure that the postal service did try to send that event over to the event plus that.

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So here are my terminal logs right here.

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This second window that I have right here.

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That's kind of highlighted is the postal service.

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I don't see any information there that's very interesting.

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If I go down to the bottom window right here that is where might event broker or event plus is living

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or actually running at present.

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It looks like there was a couple of errors here so all these errors are identical in nature.

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They'll say request failed with status for 0 4.

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So that is actually good.

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Remember as I mentioned just a moment ago our post service comment service and query service that doesn't

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exist did it exist yet does not have this post slash events end point.

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You don't have any way of actually receiving these events.

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So even though the event bus is trying to send that event off.

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Well there's nothing receive it which is why we're getting that forum for error.

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So overall I'd say this looks good.

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We are definitely emitting an event to the event bus anytime something interesting happens inside the

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post service.

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Let's take a pause right here and continue in just a moment.