feat(cdk): Generically adjust the distribution bucket CFN parameter

Author: akash1810

cdk/lib/mobile-n10n-compatibility.ts

@@ -0,0 +1,65 @@
+import type { GuStack } from '@guardian/cdk/lib/constructs/core';
+
+/**
+ * Adjusts CloudFormation parameters in a given stack (if they exist).
+ *
+ * @param stack - The stack to adjust.
+ * @param currentDefaultValue - The current default value to look for. Can be a prefix, or a full value.
+ * @param desiredDefaultValue - The desired default value to replace with. Can be a prefix, or a full value.
+ */
+function adjustParameter(
+	stack: GuStack,
+	currentDefaultValue: string,
+	desiredDefaultValue: string,
+) {
+	const parameters = Object.values(stack.parameters)
+		.filter((_) => !!_.default)
+		.filter((_) => {
+			const defaultValue = _.default as string;
+
+			// Use `startsWith` to allow for partial matches (i.e. prefixes)
+			return defaultValue.startsWith(currentDefaultValue);
+		});
+
+	parameters.forEach((parameter) => {
+		parameter.default = (parameter.default as string).replace(
+			currentDefaultValue,
+			desiredDefaultValue,
+		);
+		parameter.allowedValues = [parameter.default];
+	});
+}
+
+/**
+ * Adjusts VPC-related CloudFormation parameters in the given stack to use the `notifications` VPC.
+ * @see // https://github.com/guardian/aws-account-setup/blob/67a516b65e2e151d69687fa61a8a1aa914e8b7c0/packages/cdk/lib/__snapshots__/aws-account-setup.test.ts.snap#L27280-L27327
+ */
+function adjustVpcParameters(stack: GuStack) {
+	adjustParameter(
+		stack,
+		'/account/vpc/primary/',
+		'/account/vpc/notifications/',
+	);
+}
+
+/**
+ * Adjusts the artifact bucket parameter for n10n services.
+ * In the Mobile account there are separate artifact buckets for different groups of applications,
+ * so we can't use the account-wide default.
+ */
+function adjustArtifactBucketParameter(stack: GuStack) {
+	adjustParameter(
+		stack,
+		'/account/services/artifact.bucket',
+		'/account/services/artifact.bucket.n10n',
+	);
+}
+
+/**
+ * Applications within the `mobile-n10n` stack do not use account (/GuCDK) defaults.
+ * This adjusts CloudFormation parameters with values suitable for the `mobile-n10n` stack.
+ */
+export function adjustCloudformationParameters(stack: GuStack) {
+	adjustVpcParameters(stack);
+	adjustArtifactBucketParameter(stack);
+}

cdk/lib/registrations-db-proxy.ts

@@ -11,7 +11,7 @@ import {
 	ProxyTarget,
 } from 'aws-cdk-lib/aws-rds';
 import { Secret } from 'aws-cdk-lib/aws-secretsmanager';
-import { adjustVpcParameters } from './vpc';
+import { adjustCloudformationParameters } from './mobile-n10n-compatibility';
 
 interface DbProxyStackProps extends GuStackProps {
 	appName: string;
@@ -110,6 +110,6 @@ export class RegistrationsDbProxy extends GuStack {
 			});
 		}
 
-		adjustVpcParameters(this);
+		adjustCloudformationParameters(this);
 	}
 }

cdk/lib/report.ts

@@ -3,15 +3,14 @@ import { AccessScope } from '@guardian/cdk/lib/constants';
 import type { GuStackProps } from '@guardian/cdk/lib/constructs/core';
 import { GuVpcParameter } from '@guardian/cdk/lib/constructs/core';
 import { GuLoggingStreamNameParameter } from '@guardian/cdk/lib/constructs/core';
-import { GuDistributionBucketParameter } from '@guardian/cdk/lib/constructs/core';
 import { GuStack } from '@guardian/cdk/lib/constructs/core';
 import { GuCname } from '@guardian/cdk/lib/constructs/dns';
 import { GuAllowPolicy } from '@guardian/cdk/lib/constructs/iam';
 import type { App } from 'aws-cdk-lib';
 import { Duration } from 'aws-cdk-lib';
 import type { CfnAutoScalingGroup } from 'aws-cdk-lib/aws-autoscaling';
 import { InstanceClass, InstanceSize, InstanceType } from 'aws-cdk-lib/aws-ec2';
-import { adjustVpcParameters } from './vpc';
+import { adjustCloudformationParameters } from './mobile-n10n-compatibility';
 
 export interface ReportProps extends GuStackProps {
 	domainName:
@@ -95,14 +94,7 @@ export class Report extends GuStack {
 		// Once the YAML template has been removed we should be able to drop this override
 		vpcParameter.overrideLogicalId('GuCdkVpcId');
 
-		adjustVpcParameters(this);
-
-		// In the Mobile account there are separate artifact buckets for different groups of applications, so we can't use
-		// the account-wide default
-		const distBucketParameterName = '/account/services/artifact.bucket.n10n';
-		const distBucketParameter = GuDistributionBucketParameter.getInstance(this);
-		distBucketParameter.allowedValues = [distBucketParameterName];
-		distBucketParameter.default = distBucketParameterName;
+		adjustCloudformationParameters(this);
 
 		// In the Mobile account there are separate Kinesis streams for CODE and PROD, so we can't use the account-wide
 		// default