Readme.md

Setup DynamoDB using AWS SAM

Introduction

What is DynamoDB?

• It is a NoSQL proprietary Database by AWS
• It can sustain large amount of traffic and highly scalable (It's not relevant in our case though)
• It is also Schema-less, So we don't need to define our data-types upfront

Here, we will setup the DynamoDB and change the configuration in the infrastructure

Use Case

• Database
• API calls

Cloud Research

Here are the steps for Setting up DynamoDB using AWS SAM :

• Check the previous day documentations for the steps done till now regarding IAM, S3, CloudFormation, CloudFront, Certificate Manager and API GateWay

• Add AmazonDynamoDBFullAccess Permission to the IAM user for executing the later tasks

• Add the following Snippet to the template.yaml below Resource tab: (This adds a Table named "ronit-cloud-resume" in DynamoDB)

DynamoDBTable:
   Type: AWS::DynamoDB::Table
   Properties:
     TableName: ronit-cloud-resume
     BillingMode: PAY_PER_REQUEST
     AttributeDefinitions:
       - AttributeName: "ID"
         AttributeType: "S"
     KeySchema:
       - AttributeName: "ID"
         KeyType: "HASH"

• Run command make deploy-infra and check the tables page in AWS DynamoDB Dashboard, and Click on the table we created via template.yaml
• Click on "Explore Items" and Create an item named example

So, a Sample Table and Item is made in DynamoDB

There are two types of Architectural Patterns -->

1. Monolithic Function
(Putting all code in single Lambda Deployment)

2. Single Purposed Function
(Each Lambda per Functionality)

We are using Single Purposed Function for our case

• We will update the Lambda Functions in the template.yaml with the following snippet: (It creates get and put funtions, deleting the existing HelloWorldFunction

  GetFunction:
    Type: AWS::Serverless::Function 
    Properties:
      CodeUri: get-function/
      Handler: get-function
      Runtime: go1.x
      Architectures:
        - x86_64
      Events:
        CatchAll:
          Type: Api 
          Properties:
            Path: /get
            Method: GET
  PutFunction:
    Type: AWS::Serverless::Function 
    Properties:
      CodeUri: put-function/
      Handler: put-function
      Runtime: go1.x
      Architectures:
        - x86_64
      Events:
        CatchAll:
          Type: Api 
          Properties:
            Path: /put
            Method: GET

• We also need to replace the Hello-world folder with get-function and put-function folders

• Inside those folders, modify the go.mod for changing the function name into respective folder names

• And lastly, Change the invoke URL in JavaScript snippet of index.html by replacing hello/ with get, as mentioned below :

<script>
    fetch('https://lyurpfjw7f.execute-api.us-east-1.amazonaws.com/Prod/get')
        .then(response => response.json())
        .then((data) => {
            document.getElementById('replaceme').innerText = data.count
        })
</script>

• Run command make deploy-site and make deploy-infra to make changes to the stack
• Check if the invoke link is returning { "count": "2" } in the Browser Window

AND The DynamoDB is ready to store data over it and turn it Dynamic !

Social Proof

Representation of the Stages in the API GateWay after Deployment