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In this video, we are going to update product method for product lambda microservices with using SDK

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libraries.

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For that purpose we expect as a HTTP put request from client and Amazon API gateway to invoke our product

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Microsoft Lambda function.

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When we hit the HTTP port operation, we perform update operation from the product table of Dynamo DB

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table into our lambda function.

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So to do so, please open the studio code and go on top of the index JS file and we will add an additional

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switch statement, case statement for the HTTP port operation.

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But before that, let's check the incoming event.

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If you go to events and open the put by ID, the JSON, this is the structure of how lambda function

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triggered when performing the HTTP input operation aces method is a put.

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This is the resource and PID parameters.

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If you scroll on, you can see pet parameters in here and also you can see that this could be get the

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body information that you can update an existing attribute.

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So let's implement this function before we start.

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We should accommodate the incoming HTTP post operation.

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So that's why after the case delete operation, I would like to add a naive case which will be the.

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Days.

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Operation.

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Here.

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You can see that we have added the HTTP put operation with the body of the update product method and

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we are placing the whole event object into this method in order to perform update operation.

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So please add this case statement into your switch below of the handle method of lambda function.

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And this is the indexes we are in the main file.

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Save this file and now it is time to implement these update product function.

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Before we implement, we should understand which command that we will use during the update operation

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for that purpose.

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Open the dynamic DB Client SDK documentation and open the update item command update item command that

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we will use when editing and updating an item on Dynamo DB table.

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And here you can see the example usage and here is the input parameters that we define these properties

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when updating an item OC Let's implement this code to do so, please open the index JS file and go go

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at the end of this page.

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So now I'm going to copy and paste and explain after that.

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So basically update product is a bit complicated as you can see that it is a bit complicated in function

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that we implement this function.

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So basically if you come to documentation, you can see that as you remember that when we are performing

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update item with using the click commands, we are placing the table name, key update, expression

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and explicit attribute values and the return values.

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So these are the properties that we should define when we are using the update item command.

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So that takes some complicated code that we are going to provide into the our update product function.

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But the idea is the same.

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Before explaining this code below, let me add the required import statement.

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If you scroll down, we basically using to Marshall and we use update item command.

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Please import this update item command on top of the page after the delete command of the dynamic DB

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client import statement.

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And if you go back to our code, make sure that you have update item command imported successfully.

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So let me start explaining this method.

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Basically, we will start with the method body and this method is get a parameter which is the event

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JSON object and we are covering the case below.

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And in the first line we basically get event information, pass this information as a request request

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body to get the updated attributes.

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After that, we get the keys into these request body to get which which columns, which attribute values

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should be update and after that perform log operation.

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And after that, basically we provide the parameters for the update item command and the paste the parameters

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to the Dynamo DB client send operation.

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So a parameter so we can define these parameters.

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Basically, we will follow the same discipline into the documentation and the commands we provide the

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table name, key update, expression and expression, attribute values.

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So if you go back to our code, we can see the table name comes from the Dynamo DB table environment

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variables and see the key is an ID and we get the ID from event parameters ID and marshall this operation

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to simplify to dynamo DB key definition.

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And after that see that we have an update expression.

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We generate the automatic set statement with looking the incoming object keys of the JSON object.

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So that means in that stage I would like to show you expected HTTP put request but the payload so think

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about that we are using the HTTP operation and sent this URL.

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These are the parameters that we define in the key.

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And after that we send the payload, right.

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So these object keys is collected name and price operation and create a set keyword.

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And these values are setting in the explicit attribute values to get value information from this JSON

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payload object.

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So if you scroll down, the whole operation is the same.

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So the idea is that we will use the update item command and follow the same discipline and send this

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payload and to give these parameter variables to following the same element of the Dynamo DB API.

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So as you can see that we have successfully finished the update product operation and make sure that

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your code is identical with this code and we will see other methods in the upcoming video.