Get RDS proxy endpoint to a cross account stack

[liveFreeOrCode]

Is there a good way to get a proxy endpoint to a cross account stack?

import * as cdk from "@aws-cdk/core";
import * as rds from "@aws-cdk/aws-rds";
import * as ec2 from "@aws-cdk/aws-ec2";
import * as lambda from "@aws-cdk/aws-lambda";
import { PhysicalName } from "@aws-cdk/core";

const app = new cdk.App();

const stack1 = new cdk.Stack(app, "Stack1", {
  env: { account: "111111111", region: "us-east-1" },
});

const vpc = new ec2.Vpc(stack1, "Vpc");
const cluster = new rds.DatabaseCluster(stack1, "Database", {
  engine: rds.DatabaseClusterEngine.auroraMysql({
    version: rds.AuroraMysqlEngineVersion.VER_2_08_1,
  }),
  credentials: rds.Credentials.fromGeneratedSecret("clusteradmin"), // Optional - will default to 'admin' username and generated password
  instanceProps: { vpc },
});
const proxy = cluster.addProxy("Proxy", {
  dbProxyName: PhysicalName.GENERATE_IF_NEEDED,
  vpc,
  secrets: [cluster.secret!],
});

const stack2 = new cdk.Stack(app, "Stack2", {
  env: { account: "222222222", region: "us-west-2" },
});
new lambda.Function(stack2, "MyLayeredLambda", {
  code: new lambda.InlineCode("foo"),
  handler: "index.handler",
  runtime: lambda.Runtime.NODEJS_10_X,
  environment: {
    PROXY_ENDPOINT: proxy.endpoint,
  },
});

Results in

Error: Stack "Stack2" cannot consume a cross reference from stack "Stack1". Cross stack references are only supported for stacks deployed to the same environment or between nested stacks and their parent stack

This makes total sense, but I'm curious if there's a workaround, or a better way to do this? I'm thinking maybe use PhysicalName.GENERATE_IF_NEEDED to dbProxyName and then pass the name to the lambda and use AWS SDK in the lambda to describe endpoints using the dbProxyName? I was just hoping for something cleaner

☝️ well, that idea doesn't work either

[peterwoodworth]

There's a helpful solution described here that can help you create a cross-region reference https://stackoverflow.com/questions/59774627/cloudformation-cross-region-reference

in v2 you can simply enable this prop on your stack https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.Stack.html#crossregionreferences

[github-actions[bot]]

Hello! Reopening this discussion to make it searchable.