fix(custom-resources): unable to use a resource attributes as dictionary keys in AwsCustomResource

packages/@aws-cdk/core/lib/cfn-json.ts

@@ -43,7 +43,7 @@ export class CfnJson extends CoreConstruct implements IResolvable {
    * Normally there is no need to use this property since `CfnJson` is an
    * IResolvable, so it can be simply used as a value.
    */
-  private readonly value: Reference;
+  public readonly value: Reference;
 
   private readonly jsonString: string;
 

packages/@aws-cdk/core/lib/private/resolve.ts

@@ -154,6 +154,13 @@ export function resolve(obj: any, options: IResolveOptions): any {
     throw new Error('Trying to resolve() a Construct at ' + pathName);
   }
 
+  // respect JavaScript's toJSON(): if the object has a toJSON() method, call it
+  // and continue with the returned value.
+  if ('toJSON' in obj && typeof(obj.toJSON) === 'function') {
+    const value = obj.toJSON();
+    return resolve(value, options);
+  }
+
   const result: any = { };
   for (const key of Object.keys(obj)) {
     const resolvedKey = makeContext()[0].resolve(key);

packages/@aws-cdk/core/test/cloudformation-json.test.ts

@@ -259,6 +259,22 @@ nodeunitShim({
 
     test.done();
   },
+
+  'Respects toJSON() methods on objects'(test: Test) {
+    // GIVEN
+    const app = new App();
+    const stack = new Stack(app, 'Stack1');
+    class Foo {
+      toJSON() { return 1234; }
+    }
+
+    // WHEN
+    const actual = stack.toJsonString(new Foo());
+
+    // THEN
+    expect(stack.resolve(actual)).toStrictEqual(JSON.stringify(1234));
+    test.done();
+  },
 });
 
 /**

packages/@aws-cdk/custom-resources/lib/aws-custom-resource/aws-custom-resource.ts

@@ -371,9 +371,9 @@ export class AwsCustomResource extends CoreConstruct implements iam.IGrantable {
       serviceToken: provider.functionArn,
       pascalCaseProperties: true,
       properties: {
-        create: create && encodeBooleans(create),
-        update: props.onUpdate && encodeBooleans(props.onUpdate),
-        delete: props.onDelete && encodeBooleans(props.onDelete),
+        create: create && this.encodeJson(create),
+        update: props.onUpdate && this.encodeJson(props.onUpdate),
+        delete: props.onDelete && this.encodeJson(props.onDelete),
         installLatestAwsSdk: props.installLatestAwsSdk ?? true,
       },
     });
@@ -418,6 +418,9 @@ export class AwsCustomResource extends CoreConstruct implements iam.IGrantable {
     return this.customResource.getAttString(dataPath);
   }
 
+  private encodeJson(obj: any) {
+    return cdk.Stack.of(this).toJsonString(obj);
+  }
 }
 
 /**
@@ -452,19 +455,3 @@ function awsSdkToIamAction(service: string, action: string): string {
   const iamAction = action.charAt(0).toUpperCase() + action.slice(1);
   return `${iamService}:${iamAction}`;
 }
-
-/**
- * Encodes booleans as special strings
- */
-function encodeBooleans(object: object) {
-  return JSON.parse(JSON.stringify(object), (_k, v) => {
-    switch (v) {
-      case true:
-        return 'TRUE:BOOLEAN';
-      case false:
-        return 'FALSE:BOOLEAN';
-      default:
-        return v;
-    }
-  });
-}

packages/@aws-cdk/custom-resources/lib/aws-custom-resource/runtime/index.ts

@@ -29,15 +29,11 @@ export function flatten(object: object): { [key: string]: string } {
 }
 
 /**
- * Decodes encoded special values (booleans and physicalResourceId)
+ * Decodes encoded special values (physicalResourceId)
  */
 function decodeSpecialValues(object: object, physicalResourceId: string) {
   return JSON.parse(JSON.stringify(object), (_k, v) => {
     switch (v) {
-      case 'TRUE:BOOLEAN':
-        return true;
-      case 'FALSE:BOOLEAN':
-        return false;
       case PHYSICAL_RESOURCE_ID_REFERENCE:
         return physicalResourceId;
       default:
@@ -96,6 +92,9 @@ export async function handler(event: AWSLambda.CloudFormationCustomResourceEvent
     console.log(JSON.stringify(event));
     console.log('AWS SDK VERSION: ' + AWS.VERSION);
 
+    event.ResourceProperties.Create = decodeCall(event.ResourceProperties.Create);
+    event.ResourceProperties.Update = decodeCall(event.ResourceProperties.Update);
+    event.ResourceProperties.Delete = decodeCall(event.ResourceProperties.Delete);
     // Default physical resource id
     let physicalResourceId: string;
     switch (event.RequestType) {
@@ -185,3 +184,8 @@ export async function handler(event: AWSLambda.CloudFormationCustomResourceEvent
     });
   }
 }
+
+function decodeCall(call: string | undefined) {
+  if (!call) { return undefined; }
+  return JSON.parse(call);
+}

packages/@aws-cdk/custom-resources/test/aws-custom-resource/aws-custom-resource-provider.test.ts

@@ -60,14 +60,14 @@ test('create event with physical resource id path', async () => {
     RequestType: 'Create',
     ResourceProperties: {
       ServiceToken: 'token',
-      Create: {
+      Create: JSON.stringify({
         service: 'S3',
         action: 'listObjects',
         parameters: {
           Bucket: 'my-bucket',
         },
         physicalResourceId: PhysicalResourceId.fromResponse('Contents.1.ETag'),
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -98,15 +98,15 @@ test('update event with physical resource id', async () => {
     OldResourceProperties: {},
     ResourceProperties: {
       ServiceToken: 'token',
-      Update: {
+      Update: JSON.stringify({
         service: 'SNS',
         action: 'publish',
         parameters: {
           Message: 'hello',
           TopicArn: 'topicarn',
         },
         physicalResourceId: PhysicalResourceId.of('topicarn'),
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -131,14 +131,14 @@ test('delete event', async () => {
     PhysicalResourceId: 'physicalResourceId',
     ResourceProperties: {
       ServiceToken: 'token',
-      Create: {
+      Create: JSON.stringify({
         service: 'S3',
         action: 'listObjects',
         parameters: {
           Bucket: 'my-bucket',
         },
         physicalResourceId: PhysicalResourceId.fromResponse('Contents.1.ETag'),
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -166,13 +166,13 @@ test('delete event with Delete call and no physical resource id in call', async
     PhysicalResourceId: 'physicalResourceId',
     ResourceProperties: {
       ServiceToken: 'token',
-      Delete: {
+      Delete: JSON.stringify({
         service: 'SSM',
         action: 'deleteParameter',
         parameters: {
           Name: 'my-param',
         },
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -200,13 +200,13 @@ test('create event with Delete call only', async () => {
     RequestType: 'Create',
     ResourceProperties: {
       ServiceToken: 'token',
-      Delete: {
+      Delete: JSON.stringify({
         service: 'SSM',
         action: 'deleteParameter',
         parameters: {
           Name: 'my-param',
         },
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -234,15 +234,15 @@ test('catch errors', async () => {
     RequestType: 'Create',
     ResourceProperties: {
       ServiceToken: 'token',
-      Create: {
+      Create: JSON.stringify({
         service: 'S3',
         action: 'listObjects',
         parameters: {
           Bucket: 'my-bucket',
         },
         physicalResourceId: PhysicalResourceId.of('physicalResourceId'),
         ignoreErrorCodesMatching: 'NoSuchBucket',
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -257,68 +257,6 @@ test('catch errors', async () => {
   expect(request.isDone()).toBeTruthy();
 });
 
-test('decodes booleans', async () => {
-  const putItemFake = sinon.fake.resolves({});
-
-  AWS.mock('DynamoDB', 'putItem', putItemFake);
-
-  const event: AWSLambda.CloudFormationCustomResourceCreateEvent = {
-    ...eventCommon,
-    RequestType: 'Create',
-    ResourceProperties: {
-      ServiceToken: 'token',
-      Create: {
-        service: 'DynamoDB',
-        action: 'putItem',
-        parameters: {
-          TableName: 'table',
-          Item: {
-            True: {
-              BOOL: 'TRUE:BOOLEAN',
-            },
-            TrueString: {
-              S: 'true',
-            },
-            False: {
-              BOOL: 'FALSE:BOOLEAN',
-            },
-            FalseString: {
-              S: 'false',
-            },
-          },
-        },
-        physicalResourceId: PhysicalResourceId.of('put-item'),
-      } as AwsSdkCall,
-    },
-  };
-
-  const request = createRequest(body =>
-    body.Status === 'SUCCESS',
-  );
-
-  await handler(event, {} as AWSLambda.Context);
-
-  sinon.assert.calledWith(putItemFake, {
-    TableName: 'table',
-    Item: {
-      True: {
-        BOOL: true,
-      },
-      TrueString: {
-        S: 'true',
-      },
-      False: {
-        BOOL: false,
-      },
-      FalseString: {
-        S: 'false',
-      },
-    },
-  });
-
-  expect(request.isDone()).toBeTruthy();
-});
-
 test('restrict output path', async () => {
   const listObjectsFake = sinon.fake.resolves({
     Contents: [
@@ -340,15 +278,15 @@ test('restrict output path', async () => {
     RequestType: 'Create',
     ResourceProperties: {
       ServiceToken: 'token',
-      Create: {
+      Create: JSON.stringify({
         service: 'S3',
         action: 'listObjects',
         parameters: {
           Bucket: 'my-bucket',
         },
         physicalResourceId: PhysicalResourceId.of('id'),
         outputPath: 'Contents.0',
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -374,7 +312,7 @@ test('can specify apiVersion and region', async () => {
     RequestType: 'Create',
     ResourceProperties: {
       ServiceToken: 'token',
-      Create: {
+      Create: JSON.stringify({
         service: 'SNS',
         action: 'publish',
         parameters: {
@@ -384,7 +322,7 @@ test('can specify apiVersion and region', async () => {
         apiVersion: '2010-03-31',
         region: 'eu-west-1',
         physicalResourceId: PhysicalResourceId.of('id'),
-      } as AwsSdkCall,
+      } as AwsSdkCall),
     },
   };
 
@@ -454,15 +392,15 @@ test('installs the latest SDK', async () => {
     RequestType: 'Create',
     ResourceProperties: {
       ServiceToken: 'token',
-      Create: {
+      Create: JSON.stringify({
         service: 'SNS',
         action: 'publish',
         parameters: {
           Message: 'message',
           TopicArn: 'topic',
         },
         physicalResourceId: PhysicalResourceId.of('id'),
-      } as AwsSdkCall,
+      } as AwsSdkCall),
       InstallLatestAwsSdk: 'true',
     },
   };