aws-s3-deployment: Support CfnMapping (Fn::FindInMap) in deploy time values for Source.jsonData

[valebedu]

Describe the feature

As discussed in #25504 and addressed partially in #27237, support for Fn::FindInMap in deploy time values for Source.jsonData is still needed.

Currently, using Fn::FindInMap results in the following error:

api-infra: Error: Invalid CloudFormation reference. Key must start with any of "Ref" or "Fn::GetAtt" or "Fn::Select". Got {"Fn::FindInMap":["DefaultMapping","responseTemplate","full"]}
api-infra:     at addMarker (/Users/vale/Workspace/api/node_modules/.pnpm/aws-cdk-lib@2.143.0_constructs@10.3.0/node_modules/aws-cdk-lib/aws-s3-deployment/lib/render-data.js:1:1336)
api-infra:     at renderData (/Users/vale/Workspace/api/node_modules/.pnpm/aws-cdk-lib@2.143.0_constructs@10.3.0/node_modules/aws-cdk-lib/aws-s3-deployment/lib/render-data.js:1:799)
api-infra:     at Object.bind (/Users/vale/Workspace/api/node_modules/.pnpm/aws-cdk-lib@2.143.0_constructs@10.3.0/node_modules/aws-cdk-lib/aws-s3-deployment/lib/source.js:1:1919)
api-infra:     at Object.bind (/Users/vale/Workspace/api/node_modules/.pnpm/aws-cdk-lib@2.143.0_constructs@10.3.0/node_modules/aws-cdk-lib/aws-s3-deployment/lib/source.js:1:2306)
api-infra:     at /Users/vale/Workspace/api/node_modules/.pnpm/aws-cdk-lib@2.143.0_constructs@10.3.0/node_modules/aws-cdk-lib/aws-s3-deployment/lib/bucket-deployment.js:1:3768
api-infra:     at Array.map (<anonymous>)
api-infra:     at new BucketDeployment (/Users/vale/Workspace/api/node_modules/.pnpm/aws-cdk-lib@2.143.0_constructs@10.3.0/node_modules/aws-cdk-lib/aws-s3-deployment/lib/bucket-deployment.js:1:3749)
api-infra:     at new TypeSafeRestApi (/Users/vale/Workspace/api/node_modules/.pnpm/file+..+..+..+lab+aws-pdk+packages+pdk+dist+js+package_@aws-cdk+aws-cognito-identitypool-alph_2yxqjbpf3vtng3yuse5lau2hn4/node_modules/@aws/pdk/type-safe-api/construct/type-safe-rest-api.ts:176:5)
api-infra:     at new Api (/Users/vale/Workspace/api/packages/api/generated/infrastructure/typescript/src/api.ts:18:5)
api-infra:     at new Api (/Users/vale/Workspace/api/packages/api/infra/src/constructs/apis/api.ts:468:5)

Use Case

In large APIs with custom response templates, such as code error mappings, it's necessary to use CfnMapping to avoid CloudFormation template size limits. Repeating the same mapping multiple times causes CloudFormation to raise an error due to template size constraints. By using CfnMapping, we can maintain a single instance of the mapping, reducing the overall template size.

This is discussed here aws/aws-pdk#771

Proposed Solution

Extend the functionality introduced in #27237 to support Fn::FindInMap in deploy time values for Source.jsonData.

Other Information

No response

Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

CDK version used

2.143.0

Environment details (OS name and version, etc.)

macOS Sonoma 14.5 Apple M1 Pro

[khushail]

Right now. these are the supported functions -

aws-cdk/packages/aws-cdk-lib/aws-s3-deployment/lib/render-data.ts

Line 61 in d27de72

function addMarker(part: Ref | GetAtt | FnSelect) {

Fn:FindInMap function support makes sense given the usecase. Marking it as appropriate.
Thanks @valebedu for the FR!