AddOns Stack Fails to Create With Aurora Engine Mode Error

[BradKnowles]

The error I receive when deploying this stack is Resource handler returned message: "The engine mode serverless you requested is currently unavailable. (Service: Rds, Status Code: 400, Request ID: 937296f9-f3e3-4fe7-a11f-9d063ad1dfcf)" (RequestToken: c6a09945-6f0c-dca9-0a42-cb7fa30d79e1, HandlerErrorCode: InvalidRequest)

I'm working through the db.yml file to determine what values work for EngineVersion and EngineMode.

It appears that only certain postgres versions are allowed to be run in the serverless engine mode. I ran this CLI command to determine which ones were available in us-east-1

aws rds describe-db-engine-versions --engine aurora-postgresql --filters Name=engine-mode,Values=serverless --query 'DBEngineVersions[].[EngineVersion, DBParameterGroupFamily]' --output text

which output

11.18   aurora-postgresql11
13.9    aurora-postgresql13

The db.yml specifies 10.7

ecsworkshop-secrets-demo/copilot/todo-app/addons/db.yml

Lines 225 to 226 in cb7f16b

	EngineVersion: "10.7"
	EngineMode: serverless

Changing EngineVersion to 13.9 and DBClusterParameterGroupName to aurora-postgresql13 resolves the issue.