AWS CDK (Bare Essentials for DVA-C02)

What is AWS CDK?

AWS Cloud Development Kit (CDK) lets you define AWS infrastructure using programming languages such as TypeScript, Python, Java, C#, and Go instead of writing CloudFormation YAML/JSON manually.

Write code → CDK generates CloudFormation → CloudFormation creates AWS resources.

CDK Workflow (Remember This)

Write CDK Code
      ↓
cdk synth
      ↓
CloudFormation Template (cdk.out/)
      ↓
cdk diff (optional)
      ↓
Shows changes
      ↓
cdk deploy
      ↓
Deploys to AWS

`cdk synth`

Purpose: Generate (synthesize) the CloudFormation template.

Converts CDK code into a CloudFormation template.
Outputs the template to the cdk.out/ directory.
Lets you review the template before deployment.

Exam Tip:

"Generate CloudFormation template" = cdk synth

`cdk deploy`

Purpose: Deploy the infrastructure.

Automatically runs synth first.
Deploys the generated CloudFormation stack.
Does not stop for you to review the template.

Exam Tip:

Deploy infrastructure = cdk deploy

`cdk diff`

Purpose: Compare changes.

Compares the deployed stack with your local CDK code.
Shows what resources will be added, modified, or deleted.
Makes no changes to AWS.

Exam Tip:

View changes before deployment = cdk diff

`cdk build`

There is no standard CDK command called cdk build.

TypeScript projects may use npm run build or tsc to compile TypeScript.
This does not generate a CloudFormation template.

Exam Tip:

Compiling code ≠ Synthesizing CloudFormation

Commands to Remember

Command	Purpose
`cdk synth`	Generate CloudFormation template (`cdk.out`)
`cdk diff`	Show differences between deployed stack and local code
`cdk deploy`	Deploy CloudFormation stack to AWS
`cdk destroy`	Delete deployed stack

DVA-C02 Exam Memory Trick

synth = Synthesize template
diff = Difference
deploy = Deploy resources
destroy = Delete stack

Likely Exam Question

Which command generates a CloudFormation template that can be reviewed before deployment?

✅ Answer: cdk synth

Because it converts the CDK application into a CloudFormation template and stores it in the cdk.out/ directory before anything is deployed.