parse stage variable rather than using "as" (#3303)

Author: johnduffell

handlers/discount-api/src/index.ts

@@ -4,14 +4,14 @@ import { Router } from '@modules/routing/router';
 import { withMMAIdentityCheck } from '@modules/routing/withMMAIdentityCheck';
 import { withBodyParser } from '@modules/routing/withParsers';
 import type { Stage } from '@modules/stage';
+import { stageFromEnvironment } from '@modules/stage';
 import type {
 	ZuoraAccount,
 	ZuoraSubscription,
 } from '@modules/zuora/types/objects';
 import type { ZuoraClient } from '@modules/zuora/zuoraClient';
 import type { APIGatewayProxyResult, Handler } from 'aws-lambda';
 import dayjs from 'dayjs';
-import type { ZodType } from 'zod';
 import {
 	applyDiscountEndpoint,
 	previewDiscountEndpoint,
@@ -26,9 +26,9 @@ import {
 	applyDiscountResponseSchema,
 	previewDiscountResponseSchema,
 } from './responseSchema';
+import { stringify } from './stringify';
 
-// eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- todo fix in next refactor
-const stage = process.env.STAGE as Stage;
+const stage = stageFromEnvironment();
 
 // main entry point from AWS
 export const handler: Handler = Router([
@@ -108,7 +108,3 @@ export function previewDiscountHandler(stage: Stage) {
 		};
 	};
 }
-
-// this is a type safe version of stringify
-export const stringify = <T>(t: T, type: ZodType<T>): string =>
-	JSON.stringify(type.parse(t));

handlers/discount-api/src/stringify.ts

@@ -0,0 +1,5 @@
+import type { z } from 'zod';
+
+// this is a type safe version of stringify
+export const stringify = <T>(t: T, type: z.ZodType<T>): string =>
+	JSON.stringify(type.parse(t));

handlers/discount-api/test/stringify.test.ts

@@ -1,5 +1,5 @@
 import { z } from 'zod';
-import { stringify } from '../src/index';
+import { stringify } from '../src/stringify';
 
 test('stringify should not serialise any stray values in the object, for security reasons', () => {
 	const testSchema = z.object({

handlers/generate-product-catalog/src/index.ts

@@ -29,7 +29,7 @@ export const writeProductCatalogToS3 = async (stage: Stage) => {
 			'The generated product catalog did not pass validation in the current Zod schema: ',
 			parseResult.error,
 		);
-		await putMetric(failedSchemaValidationMetricName);
+		await putMetric(failedSchemaValidationMetricName, stage);
 	} else {
 		console.log(
 			'The generated product catalog passed validation, writing to S3',

handlers/metric-push-api/src/index.ts

@@ -1,7 +1,10 @@
 import { putMetric } from '@modules/aws/cloudwatch';
 import { Router } from '@modules/routing/router';
+import { stageFromEnvironment } from '@modules/stage';
 import type { APIGatewayProxyEvent } from 'aws-lambda';
 
+const stage = stageFromEnvironment();
+
 const validReferers = [
 	'https://support.thegulocal.com/',
 	'https://support.code.dev-theguardian.com/',
@@ -22,7 +25,7 @@ export const handler = Router([
 			const referer = event.headers.referer ?? event.headers.Referer;
 
 			if (referer && validReferers.includes(referer)) {
-				await putMetric('metric-push-api-client-side-error');
+				await putMetric('metric-push-api-client-side-error', stage);
 				return Promise.resolve(buildResponse(201));
 			} else {
 				return Promise.resolve(buildResponse(204));

handlers/metric-push-api/test/index.test.ts

@@ -2,6 +2,9 @@ import { putMetric } from '@modules/aws/cloudwatch';
 import type { APIGatewayProxyEvent } from 'aws-lambda';
 import { handler } from '../src/index';
 
+jest.mock('@modules/stage', () => ({
+	stageFromEnvironment: jest.fn(() => 'CODE'),
+}));
 jest.mock('@modules/aws/cloudwatch', () => ({
 	putMetric: jest.fn(),
 }));
@@ -60,6 +63,7 @@ describe('handler', () => {
 
 				expect(putMetric).toHaveBeenCalledWith(
 					'metric-push-api-client-side-error',
+					'CODE',
 				);
 			});
 

handlers/product-switch-api/src/index.ts

@@ -1,15 +1,14 @@
 import { Router } from '@modules/routing/router';
 import { withMMAIdentityCheck } from '@modules/routing/withMMAIdentityCheck';
 import { withParsers } from '@modules/routing/withParsers';
-import type { Stage } from '@modules/stage';
+import { stageFromEnvironment } from '@modules/stage';
 import type { Handler } from 'aws-lambda';
 import dayjs from 'dayjs';
 import { z } from 'zod';
 import { contributionToSupporterPlusEndpoint } from './productSwitchEndpoint';
 import { productSwitchRequestSchema } from './schemas';
 
-// eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- todo fix in next refactor
-const stage = process.env.STAGE as Stage;
+const stage = stageFromEnvironment();
 
 const pathParserSchema = z.object({
 	subscriptionNumber: z

handlers/promotions-lambdas/src/lib/syncHandler.ts

@@ -2,6 +2,7 @@ import type { AttributeValue as SDKAttributeValue } from '@aws-sdk/client-dynamo
 import { unmarshall } from '@aws-sdk/util-dynamodb';
 import { logger } from '@modules/routing/logger';
 import type { Stage } from '@modules/stage';
+import { stageFromEnvironment } from '@modules/stage';
 import type {
 	DynamoDBBatchResponse,
 	DynamoDBRecord,
@@ -65,10 +66,7 @@ export const createSyncHandler = <TSource, TTarget extends object>(
 
 	// build the handler
 	return async (event: DynamoDBStreamEvent): Promise<DynamoDBBatchResponse> => {
-		const stage = process.env.STAGE;
-		if (!(stage === 'CODE' || stage === 'PROD')) {
-			throw new Error('Invalid STAGE');
-		}
+		const stage = stageFromEnvironment();
 
 		const batchItemFailures: DynamoDBBatchResponse['batchItemFailures'] = [];
 

handlers/salesforce-disaster-recovery-health-check/src/handlers/salesforceDisasterRecoveryHealthCheck.ts

@@ -1,4 +1,5 @@
 import { getIfDefined } from '@modules/nullAndUndefined';
+import { stageFromEnvironment } from '@modules/stage';
 import { publishSnsMessage } from '../services/sns';
 import { describeExecution, startExecution } from '../services/step-functions';
 
@@ -10,10 +11,7 @@ export const handler = async (): Promise<
 		'APP environment variable not set',
 	);
 
-	const stage = getIfDefined<string>(
-		process.env.STAGE,
-		'STAGE environment variable not set',
-	);
+	const stage = stageFromEnvironment();
 
 	const region = getIfDefined<string>(
 		process.env.REGION,

handlers/salesforce-disaster-recovery-health-check/test/handlers/salesforceDisasterRecoveryHealthCheck.test.ts

@@ -66,7 +66,7 @@ describe('Handler', () => {
 		delete process.env.STAGE;
 
 		await expect(handler()).rejects.toThrow(
-			'STAGE environment variable not set',
+			'Stage environment variable is invalid',
 		);
 	});
 });