chore(apprunner): add validation cpu and memory for app runner (#25877)

This PR adds the same validation for the App Runner's CPU and Memory values as [CloudFormation's input patterns](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-apprunner-service-instanceconfiguration.html#cfn-apprunner-service-instanceconfiguration-cpu).

Closes #25872

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-apprunner-alpha/lib/service.ts

@@ -61,7 +61,19 @@ export class Cpu {
    *
    * @param unit custom CPU unit
    */
-  public static of(unit: string) { return new Cpu(unit); }
+  public static of(unit: string): Cpu {
+    const numericPatterns = ['256', '512', '1024', '2048', '4096'];
+    const unitPatterns = ['0.25 vCPU', '0.5 vCPU', '1 vCPU', '2 vCPU', '4 vCPU'];
+    const allowedPatterns = numericPatterns.concat(unitPatterns);
+    const isValidValue = allowedPatterns.some(
+      (pattern) => pattern === unit,
+    );
+    if (!isValidValue) {
+      throw new Error('CPU value is invalid');
+    };
+
+    return new Cpu(unit);
+  }
 
   /**
    *
@@ -126,7 +138,19 @@ export class Memory {
    *
    * @see https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-apprunner-service-instanceconfiguration.html#cfn-apprunner-service-instanceconfiguration-memory
    */
-  public static of(unit: string) { return new Memory(unit); }
+  public static of(unit: string): Memory {
+    const numericPatterns = ['512', '1024', '2048', '3072', '4096', '6144', '8192', '10240', '12288'];
+    const unitPatterns = ['0.5 GB', '1 GB', '2 GB', '3 GB', '4 GB', '6 GB', '8 GB', '10 GB', '12 GB'];
+    const allowedPatterns = numericPatterns.concat(unitPatterns);
+    const isValidValue = allowedPatterns.some(
+      (pattern) => pattern === unit,
+    );
+    if (!isValidValue) {
+      throw new Error('Memory value is invalid');
+    };
+
+    return new Memory(unit);
+  }
 
   /**
    *

packages/@aws-cdk/aws-apprunner-alpha/test/service.test.ts

@@ -899,7 +899,7 @@ test('custom IAM access role and instance role are allowed', () => {
   });
 });
 
-test('cpu and memory properties are allowed', () => {
+test('cpu and memory properties as unit values are allowed', () => {
   // GIVEN
   const app = new cdk.App();
   const stack = new cdk.Stack(app, 'demo-stack');
@@ -925,7 +925,7 @@ test('cpu and memory properties are allowed', () => {
   });
 });
 
-test('custom cpu and memory units are allowed', () => {
+test('cpu and memory properties as numeric values are allowed', () => {
   // GIVEN
   const app = new cdk.App();
   const stack = new cdk.Stack(app, 'demo-stack');
@@ -934,14 +934,14 @@ test('custom cpu and memory units are allowed', () => {
     source: apprunner.Source.fromEcrPublic({
       imageIdentifier: 'public.ecr.aws/aws-containers/hello-app-runner:latest',
     }),
-    cpu: apprunner.Cpu.of('Some vCPU'),
-    memory: apprunner.Memory.of('Some GB'),
+    cpu: apprunner.Cpu.of('1024'),
+    memory: apprunner.Memory.of('3072'),
   });
   // THEN
   Template.fromStack(stack).hasResourceProperties('AWS::AppRunner::Service', {
     InstanceConfiguration: {
-      Cpu: 'Some vCPU',
-      Memory: 'Some GB',
+      Cpu: '1024',
+      Memory: '3072',
     },
     NetworkConfiguration: {
       EgressConfiguration: {
@@ -951,6 +951,70 @@ test('custom cpu and memory units are allowed', () => {
   });
 });
 
+test('invalid cpu property as unit value is not allowed', () => {
+  // GIVEN
+  const app = new cdk.App();
+  const stack = new cdk.Stack(app, 'demo-stack');
+  // WHEN
+  expect(() => {
+    new apprunner.Service(stack, 'DemoService', {
+      source: apprunner.Source.fromEcrPublic({
+        imageIdentifier: 'public.ecr.aws/aws-containers/hello-app-runner:latest',
+      }),
+      cpu: apprunner.Cpu.of('1000 vCPU'),
+      memory: apprunner.Memory.of('3 GB'),
+    });
+  }).toThrow('CPU value is invalid');
+});
+
+test('invalid cpu property as numeric value is not allowed', () => {
+  // GIVEN
+  const app = new cdk.App();
+  const stack = new cdk.Stack(app, 'demo-stack');
+  // WHEN
+  expect(() => {
+    new apprunner.Service(stack, 'DemoService', {
+      source: apprunner.Source.fromEcrPublic({
+        imageIdentifier: 'public.ecr.aws/aws-containers/hello-app-runner:latest',
+      }),
+      cpu: apprunner.Cpu.of('1'),
+      memory: apprunner.Memory.of('3 GB'),
+    });
+  }).toThrow('CPU value is invalid');
+});
+
+test('invalid memory property as unit value is not allowed', () => {
+  // GIVEN
+  const app = new cdk.App();
+  const stack = new cdk.Stack(app, 'demo-stack');
+  // WHEN
+  expect(() => {
+    new apprunner.Service(stack, 'DemoService', {
+      source: apprunner.Source.fromEcrPublic({
+        imageIdentifier: 'public.ecr.aws/aws-containers/hello-app-runner:latest',
+      }),
+      cpu: apprunner.Cpu.of('1 vCPU'),
+      memory: apprunner.Memory.of('3000 GB'),
+    });
+  }).toThrow('Memory value is invalid');
+});
+
+test('invalid memory property as numeric value is not allowed', () => {
+  // GIVEN
+  const app = new cdk.App();
+  const stack = new cdk.Stack(app, 'demo-stack');
+  // WHEN
+  expect(() => {
+    new apprunner.Service(stack, 'DemoService', {
+      source: apprunner.Source.fromEcrPublic({
+        imageIdentifier: 'public.ecr.aws/aws-containers/hello-app-runner:latest',
+      }),
+      cpu: apprunner.Cpu.of('1 vCPU'),
+      memory: apprunner.Memory.of('3'),
+    });
+  }).toThrow('Memory value is invalid');
+});
+
 test('environment variable with a prefix of AWSAPPRUNNER should throw an error', () => {
   // GIVEN
   const app = new cdk.App();