Simple lambda that accepts an JSON object (receipt model) and save it to S3. The lambda itself was is not the focus of this project. Rather, I wanted to focus on how to deploy the lambda using aws CDK.

Read project description here

Directory Structure

save-receipt-function
  save-receipts-cdk
    src
      main
        java
          com.coffeebeans.cdk
  save-receipts-lambda
    src
      main
        java
          lambda

aws setup

I'm using AWS organisation with management account and two other account:

• development
• production

Follow these steps to create the stack in the development account (************).

~/.aws/credentials Changes

Append your ~/.aws/credentials with the following snippet

[receipts-dev]
aws_access_key_id=your_aws_access_key_id
aws_secret_access_key=your_aws_secret_access_key
region=ap-southeast-2

~/.aws/config Changes

Append your ~/.aws/config with the following snippet

[profile receipts-dev]
region=ap-southeast-2
output=json
account=::************ # while ************ is management account
role_arn=arn:aws:iam::************:role/OrganizationAccountAccessRole # while ************ is your development account 
source_profile=default
role_session_name=your_preferred_session_name

Deployment

cd /path/to/save-receipt-function
mvn clean package  
cd save-receipts-cdk
cdk bootstrap --profile receipts-dev
cdk deploy --profile receipts-dev

What will this create

• VPC
• 4 subnets (two private and two public)
• Nat gateway
• S3 bucket
• Lambda function to save files in S3
• Api gateway endpoint to allow clients call lambda as a rest endpoint.
• Roles and policies to allow RestApi call lambda and lambda to put objects in S3

Useful commands

• mvn package compile and run tests
• cdk ls list all stacks in the app
• cdk synth emits the synthesized CloudFormation template
• cdk deploy deploy this stack to your default AWS account/region
• cdk diff compare deployed stack with current state
• cdk docs open CDK documentation