make node runtime configurable

README.md

@@ -144,6 +144,7 @@ export default () => ({
 
       // optional
       memorySize: 1769, // default: `128` MB
+      lambdaRuntime: `22.x`, // default `20.x`
       timeoutInSeconds: 3, // default: `28` seconds (this is the maximum timeout)
       environment: { FOO: `bar` },
       requestParameters: { foo: {}, bar: { cacheKey: true, required: true } },

src/cdk/create-lambda-function.ts

@@ -4,6 +4,7 @@ import type { Stack } from 'aws-cdk-lib';
 import { getDomainName } from '../utils/get-domain-name.js';
 import { getHash } from '../utils/get-hash.js';
 import { getNormalizedName } from '../utils/get-normalized-name.js';
+import { mapLambdaRuntime } from '../utils/lambda-runtime.js';
 import { Duration, aws_ec2, aws_efs, aws_iam, aws_lambda, aws_logs } from 'aws-cdk-lib';
 import { basename, dirname, extname, join } from 'path';
 
@@ -84,6 +85,8 @@ export function createLambdaFunction(
       }
     : undefined;
 
+  const runtime = mapLambdaRuntime(route.lambdaRuntime);
+
   const fn = new aws_lambda.Function(stack, `Function${getHash(uniqueFunctionName)}`, {
     functionName: uniqueFunctionName,
     code: aws_lambda.Code.fromAsset(dirname(path)),
@@ -92,7 +95,7 @@ export function createLambdaFunction(
     memorySize,
     environment,
     timeout: Duration.seconds(timeoutInSeconds),
-    runtime: aws_lambda.Runtime.NODEJS_20_X,
+    runtime,
     tracing: aws_lambda.Tracing.PASS_THROUGH,
     insightsVersion:
       monitoring === true || monitoring?.lambdaInsightsEnabled

src/cdk/create-request-authorizer.ts

@@ -32,7 +32,7 @@ export function createRequestAuthorizer(
         USERNAME: authentication.username,
         PASSWORD: authentication.password,
       },
-      runtime: aws_lambda.Runtime.NODEJS_18_X,
+      runtime: aws_lambda.Runtime.NODEJS_22_X,
       tracing: aws_lambda.Tracing.PASS_THROUGH,
       logRetention: aws_logs.RetentionDays.TWO_WEEKS,
     }),

src/parse-stack-config.ts

@@ -31,13 +31,17 @@ export type LambdaRoute = Omit<z.TypeOf<typeof LambdaRouteSchema>, 'onSynthesize
 
 export type S3Route = z.TypeOf<typeof S3RouteSchema>;
 
+const LambdaRuntimeSchema = z.enum([`20.x`, `22.x`, `LATEST`]).optional();
+export type LambdaRuntime = z.TypeOf<typeof LambdaRuntimeSchema>;
+
 const LambdaRouteSchema = z.object({
   type: z.literal(`function`),
   httpMethod: z.enum([`DELETE`, `GET`, `HEAD`, `PATCH`, `POST`, `PUT`]),
   publicPath: z.string(),
   path: z.string(),
   functionName: z.string(),
   memorySize: z.number().optional(),
+  lambdaRuntime: LambdaRuntimeSchema,
   timeoutInSeconds: z.number().int().min(0).max(28).optional(),
   environment: z.record(z.string()).optional(),
   requestParameters: z

src/utils/lambda-runtime.test.ts

@@ -0,0 +1,12 @@
+import { mapLambdaRuntime } from './lambda-runtime.js';
+import { describe, expect, test } from '@jest/globals';
+import { aws_lambda } from 'aws-cdk-lib';
+
+describe(`lambda runtime utils`, () => {
+  test(`map runtime`, () => {
+    expect(mapLambdaRuntime(undefined)).toEqual(aws_lambda.Runtime.NODEJS_20_X);
+    expect(mapLambdaRuntime(`20.x`)).toEqual(aws_lambda.Runtime.NODEJS_20_X);
+    expect(mapLambdaRuntime(`22.x`)).toEqual(aws_lambda.Runtime.NODEJS_22_X);
+    expect(mapLambdaRuntime(`LATEST`)).toEqual(aws_lambda.Runtime.NODEJS_LATEST);
+  });
+});

src/utils/lambda-runtime.ts

@@ -0,0 +1,23 @@
+import type { LambdaRuntime } from '../parse-stack-config.js';
+
+import { aws_lambda } from 'aws-cdk-lib';
+
+/**
+ * Maps the lambda runtime config enum to CDK equivalents.
+ *
+ * @param lambdaRuntime the lambda config string or undefined
+ * @returns the CDK runtime constant.
+ */
+export function mapLambdaRuntime(lambdaRuntime: LambdaRuntime): aws_lambda.Runtime {
+  if (!lambdaRuntime) {
+    return aws_lambda.Runtime.NODEJS_20_X;
+  }
+  switch (lambdaRuntime) {
+    case `20.x`:
+      return aws_lambda.Runtime.NODEJS_20_X;
+    case `22.x`:
+      return aws_lambda.Runtime.NODEJS_22_X;
+    case `LATEST`:
+      return aws_lambda.Runtime.NODEJS_LATEST;
+  }
+}