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In this video, we are going to refactor out 100 method of our lambda function.

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So we basically remove unnecessary.

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These command sanctions.

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And after that, if you scroll down, you can see that we are missing something very important.

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You can see that we are still returning response with such scope to 100.

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So even we handle all HTTP methods, we don't respond back to correct statement.

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Instead of that, it is still remaining to hardcoded hello message.

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So let's modify this return statement.

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We need to return correct codes according to current operations of our product line microservices.

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First of all, it is good to cover all switch statement into case block.

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As you can see that we don't have any case block in the our main method.

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So I'm going to create a new try case block.

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And in here in the trial, look, I'm going to copy and paste to the switch statement.

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You can copy this switch statement and paste into the trial.

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Look.

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Okay, very good.

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So if everything goes well, so that means in happy bit, we basically lock the body information.

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As you can see that we have created a body information.

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Of course, we need to create a body information at the beginning of the method.

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It is really important.

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Please don't forget this line of seven.

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So create a body body variable and after that we will set body variable with incoming response from

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the these methods.

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And after that, if everything goes well in happy pat in the tribal log, I'm going to log the body

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and I'm going to return a success response.

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So let me come here and write the actual code.

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Okay.

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So as you can see that after the switch statement, we are looking to buy the information which comes

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from the these methods that we develop in the last videos.

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And after that, we are returning the score to 100 success response.

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And in the body of these return objects, we have a message which is a successful message, and we have

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a body information which comes from these methods in the message we provide.

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The event estimated that we mean that we are performing the HTTP, get post, delete and put operation

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successfully finished.

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So this is the happy part.

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What about the worst part?

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Or if we get an exception in the cache block, we got the expression and console log the exception and

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also return statement into the API gateway.

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This is important because we basically need to respond back to API gateway synchronously when our lambda

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function is triggered synchronously from any of these resources, in our case, API gateway.

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If we get an exception in this line of quotes in the try block, we should response back to the service

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code 500 and but the information which includes the message errors stack and so on.

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So let me change this catch error as a E and log.

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The E is a error and the other message and the error that comes from the E that message E that stick.

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Okay.

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Very good.

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So now we can remove the old return statement and we have successfully finished our main 100 method.

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Now, as you can see that we have two return statement.

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One is intertribal.

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Look, this means successfully finished HTTP operation and the second is the cage block.

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If something goes wrong, we send failure to perform Operation Message B to turn it 500 such code and

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detail information in the error message stack.

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The important thing is here.

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When you take link from API Gateway with synchronously, then you must return such code and the body

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object into the response.

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As you can see that we return such code and body both to site.

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Otherwise a the Willis Amazon API gateway don't show response properly, so please be careful about

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the response object when you are working with the synchronous invocations on lambda functions.

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Okay.

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Now we are ready to test our application.

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Before that let's all weave our codes.

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So if you go on top of the page, we have import statement.

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The first import statement includes almost all commands about the CRUD operations from the Dynamo DB

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SDK package.

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And after that we have Marshall and Marshall operations from the Dynamic DB Library to simplify these

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key definitions of the Dynamo DB table.

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And we have of course, Dynamo DB client object is a separate Node.js module.

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And here you can see the our main method of our product, Microsoft Lambda function.

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In the handle method, we basically have a tri cage block and after that we have a switch statement

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and accommodate all HTTP requests.

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We get post delete and put request and in the HTTP get request we are checking to create parameters,

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parameters and the all get all products.

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So in here we perform query command.

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In here we perform scan command and in here we are getting product by ID, get one single product,

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that means we will use get item command in here.

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So if you scroll down, you can see the post operation.

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We have a great product we use put item command in here in the delete method, we use delete item command

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with passing the parameters ID and we have an update product we will use again, we will use in here

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update item command with passing to parameters, we create an update product, we are passing the whole

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event object.

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And inside of this method we are passing incoming body information that we expect the body of the product

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data into Dynamo DB table.

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So you can see that after the success response, we are returning the success certificate to 100 and

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success message and the body information.

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If something goes wrong, we are returning the error message to the service code and the body information

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and if you scroll down you can see the all method implementation in here that we will cover all CRUD

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operation and we perform all method into the product microservices lambda function.

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In the next video we are going to deploy our product lambda function and after that test all architecture.