fix(synthetics): updated handler validation (#26569)

This fix updates handler validation based on Synthetic rules for [Node](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_WritingCanary_Nodejs.html#:~:text=and%20files.-,Handler%20name,-Be%20sure%20to) and [Python](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_WritingCanary_Python.html#:~:text=Packaging%20your%20canary%20files) runtimes.

Closes #26540.

----

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

Author: lpizzinidev

packages/@aws-cdk/aws-synthetics-alpha/lib/canary.ts

@@ -22,25 +22,9 @@ export class Test {
    * @param options The configuration options
    */
   public static custom(options: CustomTestOptions): Test {
-    Test.validateHandler(options.handler);
     return new Test(options.code, options.handler);
   }
 
-  /**
-   * Verifies that the given handler ends in '.handler'. Returns the handler if successful and
-   * throws an error if not.
-   *
-   * @param handler - the handler given by the user
-   */
-  private static validateHandler(handler: string) {
-    if (!handler.endsWith('.handler')) {
-      throw new Error(`Canary Handler must end in '.handler' (${handler})`);
-    }
-    if (handler.length > 21) {
-      throw new Error(`Canary Handler must be less than 21 characters (${handler})`);
-    }
-  }
-
   /**
    * Construct a Test property
    *
@@ -422,6 +406,7 @@ export class Canary extends cdk.Resource implements ec2.IConnectable {
    * Returns the code object taken in by the canary resource.
    */
   private createCode(props: CanaryProps): CfnCanary.CodeProperty {
+    this.validateHandler(props.test.handler, props.runtime);
     const codeConfig = {
       handler: props.test.handler,
       ...props.test.code.bind(this, props.test.handler, props.runtime.family),
@@ -435,6 +420,35 @@ export class Canary extends cdk.Resource implements ec2.IConnectable {
     };
   }
 
+  /**
+   * Verifies that the handler name matches the conventions given a certain runtime.
+   *
+   * @see https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-synthetics-canary-code.html#cfn-synthetics-canary-code-handler
+   * @param handler - the name of the handler
+   * @param runtime - the runtime version
+   */
+  private validateHandler(handler: string, runtime: Runtime) {
+    const oldRuntimes = [
+      Runtime.SYNTHETICS_PYTHON_SELENIUM_1_0,
+      Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_0,
+      Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_1,
+      Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_2,
+      Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_3,
+    ];
+    if (oldRuntimes.includes(runtime)) {
+      if (!handler.match(/^[0-9A-Za-z_\\-]+\.handler*$/)) {
+        throw new Error(`Canary Handler must be specified as \'fileName.handler\' for legacy runtimes, received ${handler}`);
+      }
+    } else {
+      if (!handler.match(/^([0-9a-zA-Z_-]+\/)*[0-9A-Za-z_\\-]+\.[A-Za-z_][A-Za-z0-9_]*$/)) {
+        throw new Error(`Canary Handler must be specified either as \'fileName.handler\', \'fileName.functionName\', or \'folder/fileName.functionName\', received ${handler}`);
+      }
+    }
+    if (handler.length < 1 || handler.length > 128) {
+      throw new Error(`Canary Handler length must be between 1 and 128, received ${handler.length}`);
+    }
+  }
+
   private createRunConfig(props: CanaryProps): CfnCanary.RunConfigProperty | undefined {
     if (!props.environmentVariables) {
       return undefined;

packages/@aws-cdk/aws-synthetics-alpha/test/canaries/nodejs/node_modules/folder/canary.js

@@ -1,3 +1,4 @@
+import * as path from 'path';
 import { testDeprecated } from '@aws-cdk/cdk-build-tools';
 import { Match, Template } from 'aws-cdk-lib/assertions';
 import * as ec2 from 'aws-cdk-lib/aws-ec2';
@@ -703,3 +704,89 @@ testDeprecated('Role policy generated as expected', () => {
     }],
   });
 });
+
+testDeprecated('Should create handler with path for recent runtimes', () => {
+  // GIVEN
+  const stack = new Stack();
+
+  // WHEN
+  new synthetics.Canary(stack, 'Canary', {
+    canaryName: 'mycanary',
+    test: synthetics.Test.custom({
+      handler: 'folder/canary.functionName',
+      code: synthetics.Code.fromAsset(path.join(__dirname, 'canaries')),
+    }),
+    runtime: synthetics.Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_8,
+  });
+
+  // THEN
+  Template.fromStack(stack).hasResourceProperties('AWS::Synthetics::Canary', {
+    Name: 'mycanary',
+    Code: {
+      Handler: 'folder/canary.functionName',
+    },
+    RuntimeVersion: 'syn-nodejs-puppeteer-3.8',
+  });
+});
+
+describe('handler validation', () => {
+  testDeprecated('legacy runtimes', () => {
+    const stack = new Stack();
+    expect(() => {
+      new synthetics.Canary(stack, 'Canary', {
+        test: synthetics.Test.custom({
+          handler: 'index.functionName',
+          code: synthetics.Code.fromAsset(path.join(__dirname, 'canaries')),
+        }),
+        runtime: synthetics.Runtime.SYNTHETICS_PYTHON_SELENIUM_1_0,
+      });
+    }).toThrow(/Canary Handler must be specified as 'fileName.handler' for legacy runtimes/);
+  });
+
+  testDeprecated('recent runtimes', () => {
+    const stack = new Stack();
+
+    expect(() => {
+      new synthetics.Canary(stack, 'Canary', {
+        test: synthetics.Test.custom({
+          handler: 'invalidHandler',
+          code: synthetics.Code.fromAsset(path.join(__dirname, 'canaries')),
+        }),
+        runtime: synthetics.Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_9,
+      });
+    }).toThrow(/Canary Handler must be specified either as 'fileName.handler', 'fileName.functionName', or 'folder\/fileName.functionName'/);
+
+    expect(() => {
+      new synthetics.Canary(stack, 'Canary1', {
+        test: synthetics.Test.custom({
+          handler: 'canary.functionName',
+          code: synthetics.Code.fromAsset(path.join(__dirname, 'canaries')),
+        }),
+        runtime: synthetics.Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_9,
+      });
+    }).not.toThrow();
+
+    expect(() => {
+      new synthetics.Canary(stack, 'Canary2', {
+        test: synthetics.Test.custom({
+          handler: 'folder/canary.functionName',
+          code: synthetics.Code.fromAsset(path.join(__dirname, 'canaries')),
+        }),
+        runtime: synthetics.Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_9,
+      });
+    }).not.toThrow();
+  });
+
+  testDeprecated('handler length', () => {
+    const stack = new Stack();
+    expect(() => {
+      new synthetics.Canary(stack, 'Canary1', {
+        test: synthetics.Test.custom({
+          handler: 'longHandlerName'.repeat(10) + '.handler',
+          code: synthetics.Code.fromAsset(path.join(__dirname, 'canaries')),
+        }),
+        runtime: synthetics.Runtime.SYNTHETICS_NODEJS_PUPPETEER_3_9,
+      });
+    }).toThrow(/Canary Handler length must be between 1 and 128/);
+  });
+});

packages/@aws-cdk/aws-synthetics-alpha/test/canary.test.ts

@@ -1,28 +1,28 @@
 {
-  "version": "32.0.0",
+  "version": "33.0.0",
   "files": {
-    "fe2373df587bda7e4bf68910b7be30b2042493413a6f6f2c43efab4f184d3bad": {
+    "d5b88712f80b7d8c96ddbffc883a569f5e5681cf14a985d4d0933ca3712f5110": {
       "source": {
-        "path": "asset.fe2373df587bda7e4bf68910b7be30b2042493413a6f6f2c43efab4f184d3bad.bundle",
+        "path": "asset.d5b88712f80b7d8c96ddbffc883a569f5e5681cf14a985d4d0933ca3712f5110.bundle",
         "packaging": "zip"
       },
       "destinations": {
         "current_account-current_region": {
           "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
-          "objectKey": "fe2373df587bda7e4bf68910b7be30b2042493413a6f6f2c43efab4f184d3bad.zip",
+          "objectKey": "d5b88712f80b7d8c96ddbffc883a569f5e5681cf14a985d4d0933ca3712f5110.zip",
           "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
         }
       }
     },
-    "5c382b4e425866a69d59a5cffba84fb128c5482ea37a4da5b0ddb7a5a803d15e": {
+    "df5ea21aeb8a2b4d703bce966a4cf197c3a558b9b1bd275879fa58d12447002e": {
       "source": {
         "path": "IntegCanaryTestDefaultTestDeployAssert3AD5A094.template.json",
         "packaging": "file"
       },
       "destinations": {
         "current_account-current_region": {
           "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
-          "objectKey": "5c382b4e425866a69d59a5cffba84fb128c5482ea37a4da5b0ddb7a5a803d15e.json",
+          "objectKey": "df5ea21aeb8a2b4d703bce966a4cf197c3a558b9b1bd275879fa58d12447002e.json",
           "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
         }
       }