fix(cfn-include): fails to load SAM resources

packages/@aws-cdk/cloudformation-include/test/serverless-transform.test.ts

@@ -0,0 +1,70 @@
+import * as path from 'path';
+import '@aws-cdk/assert/jest';
+import * as core from '@aws-cdk/core';
+import * as inc from '../lib';
+import * as futils from '../lib/file-utils';
+
+/* eslint-disable quote-props */
+/* eslint-disable quotes */
+
+describe('CDK Include for templates with SAM transform', () => {
+  let stack: core.Stack;
+
+  beforeEach(() => {
+    stack = new core.Stack();
+  });
+
+  test('can ingest a template with only a minimal SAM function using S3Location for CodeUri, and output it unchanged', () => {
+    includeTestTemplate(stack, 'only-minimal-sam-function-codeuri-as-s3location.yaml');
+
+    expect(stack).toMatchTemplate(
+      loadTestFileToJsObject('only-minimal-sam-function-codeuri-as-s3location.yaml'),
+    );
+  });
+
+  test('can ingest a template with only a SAM function using an array with DDB CRUD for Policies, and output it unchanged', () => {
+    includeTestTemplate(stack, 'only-sam-function-policies-array-ddb-crud.yaml');
+
+    expect(stack).toMatchTemplate(
+      loadTestFileToJsObject('only-sam-function-policies-array-ddb-crud.yaml'),
+    );
+  });
+
+  test('can ingest a template with only a minimal SAM function using a parameter for CodeUri, and output it unchanged', () => {
+    includeTestTemplate(stack, 'only-minimal-sam-function-codeuri-as-param.yaml');
+
+    expect(stack).toMatchTemplate(
+      loadTestFileToJsObject('only-minimal-sam-function-codeuri-as-param.yaml'),
+    );
+  });
+
+  test('can ingest a template with only a minimal SAM function using a parameter for CodeUri Bucket property, and output it unchanged', () => {
+    includeTestTemplate(stack, 'only-minimal-sam-function-codeuri-bucket-as-param.yaml');
+
+    expect(stack).toMatchTemplate(
+      loadTestFileToJsObject('only-minimal-sam-function-codeuri-bucket-as-param.yaml'),
+    );
+  });
+
+  test('can ingest a template with only a SAM function using an array with DDB CRUD for Policies with an Fn::If expression, and output it unchanged', () => {
+    includeTestTemplate(stack, 'only-sam-function-policies-array-ddb-crud-if.yaml');
+
+    expect(stack).toMatchTemplate(
+      loadTestFileToJsObject('only-sam-function-policies-array-ddb-crud-if.yaml'),
+    );
+  });
+});
+
+function includeTestTemplate(scope: core.Construct, testTemplate: string): inc.CfnInclude {
+  return new inc.CfnInclude(scope, 'MyScope', {
+    templateFile: _testTemplateFilePath(testTemplate),
+  });
+}
+
+function loadTestFileToJsObject(testTemplate: string): any {
+  return futils.readYamlSync(_testTemplateFilePath(testTemplate));
+}
+
+function _testTemplateFilePath(testTemplate: string) {
+  return path.join(__dirname, 'test-templates', 'sam', testTemplate);
+}

packages/@aws-cdk/cloudformation-include/test/test-templates/sam/only-minimal-sam-function-codeuri-as-param.yaml

@@ -0,0 +1,13 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Transform: AWS::Serverless-2016-10-31
+Parameters:
+  CodeLocation:
+    Type: String
+Resources:
+  MicroserviceHttpEndpoint:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: index.handler
+      Runtime: nodejs12.x
+      CodeUri:
+        Ref: CodeLocation

packages/@aws-cdk/cloudformation-include/test/test-templates/sam/only-minimal-sam-function-codeuri-as-s3location.yaml

@@ -0,0 +1,11 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Transform: AWS::Serverless-2016-10-31
+Resources:
+  MicroserviceHttpEndpoint:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: index.handler
+      Runtime: nodejs12.x
+      CodeUri:
+        Bucket: awsserverlessrepo-changesets-1f9ifp952i9h0
+        Key: 123456789012/arn:aws:serverlessrepo:us-east-1:077246666028:applications-microservice-http-endpoint-versions-1.0.4/dc38a8c1-d27f-44f3-b545-4cfff4f8b865

packages/@aws-cdk/cloudformation-include/test/test-templates/sam/only-minimal-sam-function-codeuri-bucket-as-param.yaml

@@ -0,0 +1,15 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Transform: AWS::Serverless-2016-10-31
+Parameters:
+  CodeLocation:
+    Type: String
+Resources:
+  MicroserviceHttpEndpoint:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: index.handler
+      Runtime: nodejs12.x
+      CodeUri:
+        Bucket:
+          Ref: CodeLocation
+        Key: my-key

packages/@aws-cdk/cloudformation-include/test/test-templates/sam/only-sam-function-policies-array-ddb-crud-if.yaml

@@ -0,0 +1,26 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Transform: AWS::Serverless-2016-10-31
+Conditions:
+  SomeCondition:
+    Fn::Equals: [1, 2]
+Parameters:
+  TableNameParameter:
+    Type: String
+Resources:
+  MicroserviceHttpEndpoint:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: index.handler
+      Runtime: nodejs12.x
+      CodeUri:
+        Bucket: awsserverlessrepo-changesets-1f9ifp952i9h0
+        Key: 828671620168/arn:aws:serverlessrepo:us-east-1:077246666028:applications-microservice-http-endpoint-versions-1.0.4/dc38a8c1-d27f-44f3-b545-4cfff4f8b865
+      Policies:
+      - Fn::If:
+          - SomeCondition
+          - DynamoDBCrudPolicy:
+              TableName:
+                Ref: TableNameParameter
+          - DynamoDBCrudPolicy:
+              TableName:
+                Ref: TableNameParameter

packages/@aws-cdk/cloudformation-include/test/test-templates/sam/only-sam-function-policies-array-ddb-crud.yaml

@@ -0,0 +1,16 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Transform: AWS::Serverless-2016-10-31
+Parameters:
+  TableNameParameter:
+    Type: String
+Resources:
+  MicroserviceHttpEndpoint:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: index.handler
+      Runtime: nodejs12.x
+      CodeUri: my-code-uri
+      Policies:
+      - DynamoDBCrudPolicy:
+          TableName:
+            Ref: TableNameParameter

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

@@ -10,6 +10,7 @@ import { ICfnFinder } from './from-cfn';
 import { Lazy } from './lazy';
 import { CfnReference } from './private/cfn-reference';
 import { IResolvable } from './resolvable';
+import { Mapper, Validator } from './runtime';
 import { isResolvableObject, Token } from './token';
 
 /**
@@ -78,36 +79,40 @@ export class FromCloudFormation {
     }
 
     // in all other cases, delegate to the standard mapping logic
-    return this.getArray(value, this.getString);
+    return this.getArray(this.getString)(value);
   }
 
-  public static getArray<T>(value: any, mapper: (arg: any) => T): T[] {
-    if (!Array.isArray(value)) {
-      // break the type system, and just return the given value,
-      // which hopefully will be reported as invalid by the validator
-      // of the property we're transforming
-      // (unless it's a deploy-time value,
-      // which we can't map over at build time anyway)
-      return value;
-    }
+  public static getArray<T>(mapper: (arg: any) => T): (x: any) => T[] {
+    return (value: any) => {
+      if (!Array.isArray(value)) {
+        // break the type system, and just return the given value,
+        // which hopefully will be reported as invalid by the validator
+        // of the property we're transforming
+        // (unless it's a deploy-time value,
+        // which we can't map over at build time anyway)
+        return value;
+      }
 
-    return value.map(mapper);
+      return value.map(mapper);
+    };
   }
 
-  public static getMap<T>(value: any, mapper: (arg: any) => T): { [key: string]: T } {
-    if (typeof value !== 'object') {
-      // if the input is not a map (= object in JS land),
-      // just return it, and let the validator of this property handle it
-      // (unless it's a deploy-time value,
-      // which we can't map over at build time anyway)
-      return value;
-    }
+  public static getMap<T>(mapper: (arg: any) => T): (x: any) => { [key: string]: T } {
+    return (value: any) => {
+      if (typeof value !== 'object') {
+        // if the input is not a map (= object in JS land),
+        // just return it, and let the validator of this property handle it
+        // (unless it's a deploy-time value,
+        // which we can't map over at build time anyway)
+        return value;
+      }
 
-    const ret: { [key: string]: T } = {};
-    for (const [key, val] of Object.entries(value)) {
-      ret[key] = mapper(val);
-    }
-    return ret;
+      const ret: { [key: string]: T } = {};
+      for (const [key, val] of Object.entries(value)) {
+        ret[key] = mapper(val);
+      }
+      return ret;
+    };
   }
 
   public static getCfnTag(tag: any): CfnTag {
@@ -118,6 +123,23 @@ export class FromCloudFormation {
         value: tag.Value,
       };
   }
+
+  /**
+   * Return a function that, when applied to a value, will return the first validly deserialized one
+   */
+  public static getTypeUnion(validators: Validator[], mappers: Mapper[]): (x: any) => any {
+    return (value: any): any => {
+      for (let i = 0; i < validators.length; i++) {
+        const candidate = mappers[i](value);
+        if (validators[i](candidate).isSuccess) {
+          return candidate;
+        }
+      }
+
+      // if nothing matches, just return the input unchanged, and let validators catch it
+      return value;
+    };
+  }
 }
 
 /**

packages/@aws-cdk/core/lib/stack.ts

@@ -964,20 +964,32 @@ function mergeSection(section: string, val1: any, val2: any): any {
         throw new Error(`Conflicting CloudFormation template versions provided: '${val1}' and '${val2}`);
       }
       return val1 ?? val2;
+    case 'Transform':
+      return mergeSets(val1, val2);
     case 'Resources':
     case 'Conditions':
     case 'Parameters':
     case 'Outputs':
     case 'Mappings':
     case 'Metadata':
-    case 'Transform':
       return mergeObjectsWithoutDuplicates(section, val1, val2);
     default:
       throw new Error(`CDK doesn't know how to merge two instances of the CFN template section '${section}' - ` +
         'please remove one of them from your code');
   }
 }
 
+function mergeSets(val1: any, val2: any): any {
+  const array1 = val1 == null ? [] : (Array.isArray(val1) ? val1 : [val1]);
+  const array2 = val2 == null ? [] : (Array.isArray(val2) ? val2 : [val2]);
+  for (const value of array2) {
+    if (!array1.includes(value)) {
+      array1.push(value);
+    }
+  }
+  return array1.length === 1 ? array1[0] : array1;
+}
+
 function mergeObjectsWithoutDuplicates(section: string, dest: any, src: any): any {
   if (typeof dest !== 'object') {
     throw new Error(`Expecting ${JSON.stringify(dest)} to be an object`);