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In this video, we are going to learn learn the asynchronous invocation and the Lambda Destinations.

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So far, we have seen that we can add trigger to lambda function.

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But now we also see on the right hand side, which is the eighth destination of our lambda function,

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which is the lambda destinations.

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We can see these triggers and destinations when creating a lambda function from the management console.

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Let me explain.

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What is Lambda destinations?

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Lambda can define destinations.

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One invoke asynchronous way.

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We can set destinations on success or on faith events after invocation is done.

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So we can also configure Lambda to send an invocation record to another services.

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Lambda supports the destinations for asynchronous invocation.

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You can see the image on the slide.

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So basically we can designate the incoming invocation to Amazon, asks Amazon Sass a lambda and event.

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So the invocation record contains details about the request and the response.

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In JSON format, we can configure separate destinations for events that are processed successfully and

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events that fail all processing attempts.

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Alternatively, we can configure an Amazon case or Amazon SMS topic as a data queue for discarded events

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for that digital cuz lambda only sends the content of the event without detail about the response.

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So we set that we can configure destinations for asynchronous invocation on lambda function in order

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to send the records of asynchronous invocation to another services.

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We can add a destination to our lambda function.

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That means we can configure separate destinations for event that fail processing or the events that

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are successful process it like error handling settings.

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We can configure destinations on a function, on a version or an alias.

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So you can see the image on the slide that shows a function that is processing asynchronous invocations

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when the function returns a success response or exit without throwing any error.

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Lambda sends a record of the invocation to an event.

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Event plus.

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So when an error fails all processing atom's lambda sends an invocation record to Amazon q.

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You can see the image in here.

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We are processing the asynchronous invocation.

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So that's why there's the event queue, which is the internal event of lambda function.

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When the invocation successfully finished, it can be redirect or destination to the successful event

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to the Amazon event page.

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But if the invocation got exception in two times, so that means the invocation record is processing

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the own fail process, which is the Amazon queue in the failure event destinations.

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In order to send events to the destination lambda function needs to additional permissions.

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We should add the policy with the required permission to our lambda function execution rules.

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Each destination service requires a different permissions.

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You can see that, for example, Amazon is required to send message permission SNS required to publish

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lambda, required to invoke function event which required the events, put event policy and permissions

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should be included or in execution role on the lambda function.

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As you can see that we have launched a lambda asynchronous invocation and the lambda destination.