s3-lambda-api.yaml

---
AWSTemplateFormatVersion: "2010-09-09"

Description: Depository app using S3, Lambda, and API Gateway

Resources:
  DepositoryS3Bucket:
    Type: "AWS::S3::Bucket"
    Properties:
      BucketName: depositorybalance24

  DepositoryLambdaExecutionRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
            Action:
              - "sts:AssumeRole"
      Description: IAM Role for Lambda to access S3
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AmazonS3FullAccess
      RoleName: DepositoryLambdaExecutionRole

  DepositoryLambdaFunction:
    DependsOn: DepositoryLambdaExecutionRole
    Type: AWS::Lambda::Function
    Properties:
      Runtime: nodejs16.x
      Role: !GetAtt DepositoryLambdaExecutionRole.Arn
      Handler: index.handler
      Code:
        ZipFile: |
          const AWS = require("aws-sdk");
          const s3 = new AWS.S3();

          exports.handler = async (event) => {
            // const { bucketName, objKey } = event;
            const bucketName = "depositorybalance24";
            const objKey = "depositoryBalance.json";

            const params = {
              Bucket: bucketName,
              Key: objKey,
            };

            try {
              const s3Object = await s3.getObject(params).promise();
              console.log(s3Object.Body.toString());
              return s3Object.Body.toString();
            } catch (err) {
              console.log(err);
              throw err;
            }
          };
      Description: Lambda function to read a S3 depository file
      Timeout: 60

  DepositoryRESTAPI:
    Type: AWS::ApiGateway::RestApi
    Properties:
      Name: DepositoryStatusAPI
      Description: Depository Status API

  DepositoryStatusResource:
    Type: AWS::ApiGateway::Resource
    Properties:
      ParentId: !GetAtt DepositoryRESTAPI.RootResourceId
      PathPart: depository-status
      RestApiId: !Ref DepositoryRESTAPI