How does cdk synth work?

[chanh-t]

I'm curious about the internal workings of cdk synth. How does the all these apps, stacks, and constructs turn in to a JSON file? I'm curious about how it works internally, end to end. What files should I read? Maybe articles as well?

[ashrafee-dev]

Main files: synthesis.ts, stack.ts, and cfn-resource.ts.

When you run cdk synth, CDK walks the construct tree. Each resource contributes its CloudFormation fragment through _toCloudFormation(), and the stack combines those fragments into the final CloudFormation template JSON written to cdk.out/.