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In this video.

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Let's see how we can handle errors gracefully inside our application.

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And for error handling, we have a section where we talk about it in detail.

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So let's see how we are going to implement that one inside our application.

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All right.

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So let's see how we are going to implement that.

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So inside the metaverse, I'm going to create one file called Global Error handler for error handling

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in experts.

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This how we created count and going to be as global.

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Is equal to function core as that.

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And inside here, instead of two or three arguments, we are going to parse in for a given error request

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response.

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And next.

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So any time experts see this kind of function, it health experts that this is error handling.

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So inside here we are going to return the error that has been okay inside our application.

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So let's have the properties that we want to send back to the user.

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First one going to be the starters.

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And for this we can send our custom message, for example, failed or something happened.

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Or server error so we can send any type of these messages.

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The next one is going to be the actual message.

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And this one, who is the actual error that has occurred inside our application?

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For example, if a user is trying to log in with invalid login credentials, we have access to that

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on the message and I will show you as you move on the next one going to be the stack the stack represents

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which file a particular error occurred and which line of code that error occurred.

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So let's build up these properties.

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So we're going to be as const stock is equal to and we have access to this properties on the error that

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we threw.

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So inside the controls, let me show you where we are throwing an error.

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Let's get back to the users, which is this.

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We can see that here.

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If a user is being found, we are through in what is called status with this and then the message.

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So we have access to this properties inside the global arrow handler.

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But before we can have access to the arrows inside the global arrow handler here, unless we create

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a specific function for it.

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For the meantime, let's see how we can cut and send in the arrow.

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All right.

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So here on the arrow that came back, we have access to the stock as error dot stock.

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The next one going to be the actual message, cast message.

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And we have it on the error dot message and the starter is going to be starters is equal to the error.

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Dart starters.

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So in case a user provides starters, then you go ahead and use the error starters.

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Otherwise we are going to use the default or failed and we can also send the status code.

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So it's going to be status code is equal to the error.

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If the user provide the status code upon throwing an error, we are going to use the error dot status

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code.

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Otherwise we use 500 million server error and let's send the response.

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It's going to be as red dot status and we are going to use the status code and we are going to chain

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with the JSON and we are going to send the message, then the stock and then the starters about the

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message.

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So here, let me rearrange.

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This one status.

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So let me bring the starters before the message.

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The arrangement doesn't matter here.

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Last step is we need to export module.

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The exports is equal to global error handler.

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So let's make use of that.

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So let's get back to the set of file, which is this, and let's require the global error handler.

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And like I said, we need to bring the error handler below all your route.

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And this is a comment we have down here and make use of app don't use the pass in the global arrow handler.

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This one anywhere in our code where we throw an error are going to have access to that and send back

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as a response to the user.

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So let's try to register a user with the same details and let's see what we're going to have.

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And you can see that we have what is called user already exists.

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And this is not an error because here we have the status quo, meaning everything is okay and we go

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back this and this is an error.

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So let's see how we can through rare error or some rare error whereby our global error handler will

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catch it.

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Let's get into that in the next video.