add a stack reference on backend resources

[josefaidt]

Environment information

System:
  OS: macOS 14.3.1
  CPU: (10) arm64 Apple M1 Pro
  Memory: 103.66 MB / 32.00 GB
  Shell: /opt/homebrew/bin/fish
Binaries:
  Node: 20.11.1 - ~/Library/Caches/fnm_multishells/47118_1712176426928/bin/node
  Yarn: 1.22.19 - ~/Library/Caches/fnm_multishells/47118_1712176426928/bin/yarn
  npm: 10.2.4 - ~/Library/Caches/fnm_multishells/47118_1712176426928/bin/npm
  pnpm: 8.15.5 - ~/Library/Caches/fnm_multishells/47118_1712176426928/bin/pnpm
NPM Packages:
  @aws-amplify/backend: 0.13.0-beta.15
  @aws-amplify/backend-cli: 0.12.0-beta.17
  aws-amplify: 6.0.27
  aws-cdk: 2.135.0
  aws-cdk-lib: 2.135.0
  typescript: 5.4.3
AWS environment variables:
  AWS_PROFILE = josef-gen2
  AWS_STS_REGIONAL_ENDPOINTS = regional
  AWS_NODEJS_CONNECTION_REUSE_ENABLED = 1
  AWS_SDK_LOAD_CONFIG = 1
No CDK environment variables

Description

It can be cumbersome to import Stack to get a stack reference on a backend resource created with a define* function. This is typically reached for when I add a custom policy or some additional resource with CDK that requires a scope.

To remove the need for importing Stack and referencing the stack of resources, add a property/method to reference the stack

from

import { defineBackend } from "@aws-amplify/backend"
import { Stack } from "aws-cdk-lib/core"
import { auth } from "./auth/resource"
import { data } from "./data/resource"

const backend = defineBackend({
  auth,
  data,
})

// pick an arbitrary resource to resolve the stack
const authStack = Stack.of(backend.auth.resources.userPool)

to

import { defineBackend } from "@aws-amplify/backend"
import { auth } from "./auth/resource"
import { data } from "./data/resource"

const backend = defineBackend({
  auth,
  data,
})

const authStack = backend.auth.stack

[ykethan]

Marking as feature request to support to referencing stack as a method or property.