bug(cli): bootstrapping multiple environments with same bootstrap-bucket-name causes inconsistent stack creation

[iankhou]

Bootstrap fails when multiple environments are being bootstrapped with a custom bucketName

Description

Users can pass in BootstrappingParameters to modify how resources are created during bootstrap:

aws-cdk-cli/packages/aws-cdk/lib/api/bootstrap/bootstrap-props.ts

Lines 66 to 72 in 7517ecc

	export interface BootstrappingParameters {
	/**
	* The name to be given to the CDK Bootstrap bucket.
	*
	* @default - a name is generated by CloudFormation.
	*/
	readonly bucketName?: string;

If bucketName is passed in, bootstrap will attempt to create the bucket. If the bucket already exists, the bootstrap operation will fail.

When bootstrapping multiple environments, it is possible to pass in bucketName. However, this will cause at least one environment to fail bootstrapping. Assuming the bucket name is not already taken, the first environment that is bootstrapped will use that bucket name and succeed. All other environments will fail to bootstrap, since the bucket name is already taken.

Reproduction

Command-line:

cdk bootstrap --all \
  --bootstrap-bucket-name my-custom-parameters-bucket-481665128236 \
  aws://481665128236/us-east-2 \
  aws://481665128236/us-west-1

Result:

Only one environment is bootstrapped successfully.

Proposed fix

BootstrappingParameters should be passed in per-environment. It should remain optional. The current CLI implementation is as follows:

aws-cdk-cli/packages/aws-cdk/lib/cli/cdk-toolkit.ts

Lines 963 to 989 in 7517ecc

	public async bootstrap(
	userEnvironmentSpecs: string[],
	options: BootstrapEnvironmentOptions,
	): Promise<void> {
	const bootstrapper = new Bootstrapper(options.source, { ioHost: this.ioHost, action: 'bootstrap' });
	// If there is an '--app' argument and an environment looks like a glob, we
	// select the environments from the app. Otherwise, use what the user said.
	const environments = await this.defineEnvironments(userEnvironmentSpecs);
	const limit = pLimit(20);
	// eslint-disable-next-line @cdklabs/promiseall-no-unbounded-parallelism
	await Promise.all(environments.map((environment) => limit(async () => {
	success(' ⏳ Bootstrapping environment %s...', chalk.blue(environment.name));
	try {
	const result = await bootstrapper.bootstrapEnvironment(environment, this.props.sdkProvider, options);
	const message = result.noOp
	? ' ✅ Environment %s bootstrapped (no changes).'
	: ' ✅ Environment %s bootstrapped.';
	success(message, chalk.blue(environment.name));
	} catch (e) {
	error(' ❌ Environment %s failed bootstrapping: %s', chalk.blue(environment.name), e);
	throw e;
	}
	})));
	}

BootstrapEnvironmentOptions is bootstrap-action-scoped (i.e. account-scoped), but it is passed into bootstrapEnvironment, an environment-scoped (i.e. region-scoped) function.

Consider something like the following as a param for bootstrap:

interface EnvironmentBootstrapConfig {
  readonly environment: string;  // The environment descriptor (e.g. 'aws://123456789012/us-east-1')
  readonly parameters?: BootstrappingParameters;
  // Other environment-specific options that were previously in BootstrapOptions
}