[ssm] BucketName: "dummy-value-for-" results in unpredictable behavior

SystemsManager parameter lookup returns “dummy-value-for-XXXX” at first run. But if used as a part of BucketName, this throws an exception on invalid bucket name

This results in unpredictable behavior

• synth/deploy may work for several code changes in a row,
• and fail miserably after cdk context --clear

Reproduction Steps

var bucketName = StringParameter.ValueFromLookup(stack, "/ssm/param/bucketName");
var bucketProps = new BucketProps { BucketName = bucketName, }

Error Log

Unhandled exception. Amazon.JSII.Runtime.JsiiException: Invalid S3 bucket name (value: logs.dummy-value-for-/ssm/param/bucketName)
Bucket name must be at least 3 and no more than 63 characters
Bucket name must only contain lowercase characters and the symbols, period (.) and dash (-) (offset: 21)

Environment

• cdk --version 1.51.0 (build 8c2d53c)

• Node.js Version: v12.7.0
• OS: Windows
• Language (Version): C#

Other

Can you please check for dummy and not throw from resource constructors? You do check for tokens already, don’t you?

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This is 🐛 Bug Report

[jsamarziya]

A potential workaround might be to use StringParameter.valueForStringParameter() instead of StringParameter.valueFromLookup(). That method returns a token instead of a string, and I found that it worked for me in the case of

s3.Bucket.fromBucketName(stack, "MyBucket", ssm.StringParameter.valueForStringParameter(stack, "myBucketParamName"))

[gel1123]

Almost the same problem occurs when specifying a custom domain in API Gateway.