AWS CDK - Cannot use tokens in construct ID - How do I dynamically name constructs based off the names of other constructs?

Question

I want to create the same CW alarm/metrics for a number of DynamoDB tables in cdk, my instinct was to try to use a for loop to append the name of the DDB table to the CW alarm, but doing so generates the following error: Cannot use tokens in construct ID

It makes sense, because the token has yet to be evaluated so its just a placeholder value. But then what would a good alternative be to sequentially naming the alarms?

My usecase isn't that complicated I could just repeat the same code X times and tweak the name each time, but that seems like an incorrect approach.

I'm using the bellow code for inspiration, but I can't see what values I can call on that wouldn't trigger this error.

https://aws.amazon.com/blogs/developer/aws-cdk-developer-preview/

Answer 1

You should use the id or uniqueId of the table, something like:

for (const table of tables) {
  new cloudwatch.Alarm(this, `AlarmFor${table.node.id}`, ...); // or table.node.uniqueId
}

But a better pattern could be to create a TableWithAlarm construct and instantiate it multiple times in your stack.