fix(allow ITable for dynamodb stream patterns) (#214)

* fix(allow ITable for dynamodb stream patterns)

* fix(allow ITable for dynamodb stream patterns)

* fixing the cfn nag issues

* PR feedback

Author: hnishar

source/patterns/@aws-solutions-constructs/aws-dynamodb-stream-lambda-elasticsearch-kibana/README.md

@@ -63,7 +63,7 @@ _Parameters_
 |existingLambdaObj?|[`lambda.Function`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda.Function.html)|Existing instance of Lambda Function object, providing both this and `lambdaFunctionProps` will cause an error.|
 |lambdaFunctionProps?|[`lambda.FunctionProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda.FunctionProps.html)|User provided props to override the default props for the Lambda function.|
 |dynamoTableProps?|[`dynamodb.TableProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.TableProps.html)|Optional user provided props to override the default props for DynamoDB Table|
-|existingTableObj?|[`dynamodb.Table`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.Table.html)|Existing instance of DynamoDB table object, providing both this and `dynamoTableProps` will cause an error.|
+|existingTableInterface?|[`dynamodb.ITable`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.ITable.html)|Existing instance of DynamoDB table object or interface, providing both this and `dynamoTableProps` will cause an error.|
 |dynamoEventSourceProps?|[`aws-lambda-event-sources.DynamoEventSourceProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda-event-sources.DynamoEventSourceProps.html)|Optional user provided props to override the default props for DynamoDB Event Source|
 |esDomainProps?|[`elasticsearch.CfnDomainProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-elasticsearch.CfnDomainProps.html)|Optional user provided props to override the default props for the Elasticsearch Service|
 |domainName|`string`|Domain name for the Cognito and the Elasticsearch Service|
@@ -73,7 +73,8 @@ _Parameters_
 
 | **Name**     | **Type**        | **Description** |
 |:-------------|:----------------|-----------------|
-|dynamoTable|[`dynamodb.Table`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.Table.html)|Returns an instance of dynamodb.Table created by the construct|
+|dynamoTableInterface|[`dynamodb.ITable`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.ITable.html)|Returns an instance of dynamodb.ITable created by the construct|
+|dynamoTable?|[`dynamodb.Table`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.Table.html)|Returns an instance of dynamodb.Table created by the construct. IMPORTANT: If existingTableInterface was provided in Pattern Construct Props, this property will be `undefined`|
 |lambdaFunction|[`lambda.Function`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda.Function.html)|Returns an instance of lambda.Function created by the construct|
 |userPool|[`cognito.UserPool`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-cognito.UserPool.html)|Returns an instance of cognito.UserPool created by the construct|
 |userPoolClient|[`cognito.UserPoolClient`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-cognito.UserPoolClient.html)|Returns an instance of cognito.UserPoolClient created by the construct|

source/patterns/@aws-solutions-constructs/aws-dynamodb-stream-lambda-elasticsearch-kibana/lib/index.ts

@@ -51,7 +51,7 @@ export interface DynamoDBStreamToLambdaToElasticSearchAndKibanaProps {
    *
    * @default - None
    */
-  readonly existingTableObj?: dynamodb.Table,
+  readonly existingTableInterface?: dynamodb.ITable,
   /**
    * Optional user provided props to override the default props
    *
@@ -101,7 +101,8 @@ export class DynamoDBStreamToLambdaToElasticSearchAndKibana extends Construct {
   private dynamoDBStreamToLambda: DynamoDBStreamToLambda;
   private lambdaToElasticSearchAndKibana: LambdaToElasticSearchAndKibana;
   public readonly lambdaFunction: lambda.Function;
-  public readonly dynamoTable: dynamodb.Table;
+  public readonly dynamoTableInterface: dynamodb.ITable;
+  public readonly dynamoTable?: dynamodb.Table;
   public readonly userPool: cognito.UserPool;
   public readonly userPoolClient: cognito.UserPoolClient;
   public readonly identityPool: cognito.CfnIdentityPool;
@@ -126,7 +127,7 @@ export class DynamoDBStreamToLambdaToElasticSearchAndKibana extends Construct {
       lambdaFunctionProps: props.lambdaFunctionProps,
       dynamoEventSourceProps: props.dynamoEventSourceProps,
       dynamoTableProps: props.dynamoTableProps,
-      existingTableObj: props.existingTableObj,
+      existingTableInterface: props.existingTableInterface,
       deploySqsDlqQueue: props.deploySqsDlqQueue,
       sqsDlqQueueProps: props.sqsDlqQueueProps
     };
@@ -146,6 +147,7 @@ export class DynamoDBStreamToLambdaToElasticSearchAndKibana extends Construct {
     this.lambdaToElasticSearchAndKibana = new LambdaToElasticSearchAndKibana(this, 'LambdaToElasticSearch', _props2);
 
     this.dynamoTable = this.dynamoDBStreamToLambda.dynamoTable;
+    this.dynamoTableInterface = this.dynamoDBStreamToLambda.dynamoTableInterface;
     this.userPool = this.lambdaToElasticSearchAndKibana.userPool;
     this.userPoolClient = this.lambdaToElasticSearchAndKibana.userPoolClient;
     this.identityPool = this.lambdaToElasticSearchAndKibana.identityPool;

source/patterns/@aws-solutions-constructs/aws-dynamodb-stream-lambda/README.md

@@ -58,14 +58,15 @@ _Parameters_
 |existingLambdaObj?|[`lambda.Function`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda.Function.html)|Existing instance of Lambda Function object, providing both this and `lambdaFunctionProps` will cause an error.|
 |lambdaFunctionProps?|[`lambda.FunctionProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda.FunctionProps.html)|User provided props to override the default props for the Lambda function.|
 |dynamoTableProps?|[`dynamodb.TableProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.TableProps.html)|Optional user provided props to override the default props for DynamoDB Table|
-|existingTableObj?|[`dynamodb.Table`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.Table.html)|Existing instance of DynamoDB table object, providing both this and `dynamoTableProps` will cause an error.|
+|existingTableInterface?|[`dynamodb.ITable`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.ITable.html)|Existing instance of DynamoDB table object or interface, providing both this and `dynamoTableProps` will cause an error.|
 |dynamoEventSourceProps?|[`aws-lambda-event-sources.DynamoEventSourceProps`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda-event-sources.DynamoEventSourceProps.html)|Optional user provided props to override the default props for DynamoDB Event Source|
 
 ## Pattern Properties
 
 | **Name**     | **Type**        | **Description** |
 |:-------------|:----------------|-----------------|
-|dynamoTable|[`dynamodb.Table`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.Table.html)|Returns an instance of dynamodb.Table created by the construct|
+|dynamoTableInterface|[`dynamodb.ITable`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.ITable.html)|Returns an instance of dynamodb.ITable created by the construct|
+|dynamoTable?|[`dynamodb.Table`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-dynamodb.Table.html)|Returns an instance of dynamodb.Table created by the construct. IMPORTANT: If existingTableInterface was provided in Pattern Construct Props, this property will be `undefined`|
 |lambdaFunction|[`lambda.Function`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-lambda.Function.html)|Returns an instance of lambda.Function created by the construct|
 
 ## Lambda Function

source/patterns/@aws-solutions-constructs/aws-dynamodb-stream-lambda/lib/index.ts

@@ -45,7 +45,7 @@ export interface DynamoDBStreamToLambdaProps {
    *
    * @default - None
    */
-  readonly existingTableObj?: dynamodb.Table,
+  readonly existingTableInterface?: dynamodb.ITable,
   /**
    * Optional user provided props to override the default props
    *
@@ -69,7 +69,8 @@ export interface DynamoDBStreamToLambdaProps {
 
 export class DynamoDBStreamToLambda extends Construct {
   public readonly lambdaFunction: lambda.Function;
-  public readonly dynamoTable: dynamodb.Table;
+  public readonly dynamoTableInterface: dynamodb.ITable;
+  public readonly dynamoTable?: dynamodb.Table;
 
   /**
    * @summary Constructs a new instance of the LambdaToDynamoDB class.
@@ -88,20 +89,20 @@ export class DynamoDBStreamToLambda extends Construct {
       lambdaFunctionProps: props.lambdaFunctionProps
     });
 
-    this.dynamoTable = defaults.buildDynamoDBTableWithStream(this, {
+    [this.dynamoTableInterface, this.dynamoTable] = defaults.buildDynamoDBTableWithStream(this, {
       dynamoTableProps: props.dynamoTableProps,
-      existingTableObj: props.existingTableObj
+      existingTableInterface: props.existingTableInterface
     });
 
     // Grant DynamoDB Stream read perimssion for lambda function
-    this.dynamoTable.grantStreamRead(this.lambdaFunction.grantPrincipal);
+    this.dynamoTableInterface.grantStreamRead(this.lambdaFunction.grantPrincipal);
 
     // Add the Lambda event source mapping
     const eventSourceProps = defaults.DynamoEventSourceProps(this, {
       eventSourceProps: props.dynamoEventSourceProps,
       deploySqsDlqQueue: props.deploySqsDlqQueue,
       sqsDlqQueueProps: props.sqsDlqQueueProps
     });
-    this.lambdaFunction.addEventSource(new DynamoEventSource(this.dynamoTable, eventSourceProps));
+    this.lambdaFunction.addEventSource(new DynamoEventSource(this.dynamoTableInterface, eventSourceProps));
   }
 }

source/patterns/@aws-solutions-constructs/aws-dynamodb-stream-lambda/test/dynamodb-stream-lambda.test.ts

@@ -185,13 +185,37 @@ test('check dynamodb table stream override', () => {
 
 });
 
-test('check getter methods', () => {
+test('check getter methods without existingTableInterface', () => {
   const stack = new cdk.Stack();
 
   const construct: DynamoDBStreamToLambda = deployNewFunc(stack);
 
-  expect(construct.lambdaFunction !== null);
-  expect(construct.dynamoTable !== null);
+  expect(construct.lambdaFunction).toBeInstanceOf(lambda.Function);
+  expect(construct.dynamoTableInterface).toHaveProperty('tableName');
+  expect(construct.dynamoTable).toBeInstanceOf(dynamodb.Table);
+  expect(construct.dynamoTable).toHaveProperty('addGlobalSecondaryIndex');
+});
+
+test('check getter methods with existingTableInterface', () => {
+  const stack = new cdk.Stack();
+
+  const construct: DynamoDBStreamToLambda = new DynamoDBStreamToLambda(stack, 'test', {
+    existingTableInterface: new dynamodb.Table(stack, 'table', {
+      partitionKey: {
+        name: 'id',
+        type: dynamodb.AttributeType.STRING
+      },
+      stream: dynamodb.StreamViewType.NEW_AND_OLD_IMAGES
+    }),
+    lambdaFunctionProps: {
+      code: lambda.Code.fromAsset(`${__dirname}/lambda`),
+      runtime: lambda.Runtime.NODEJS_12_X,
+      handler: 'index.handler'
+    },
+  });
+
+  expect(construct.lambdaFunction).toBeInstanceOf(lambda.Function);
+  expect(construct.dynamoTable).toBeUndefined();
 });
 
 test('check exception for Missing existingObj from props', () => {
@@ -205,4 +229,70 @@ test('check exception for Missing existingObj from props', () => {
   } catch (e) {
     expect(e).toBeInstanceOf(Error);
   }
-});
+});
+
+test('check dynamodb table stream override with ITable', () => {
+  const stack = new cdk.Stack();
+  const existingTableInterface = dynamodb.Table.fromTableAttributes(stack, 'existingtable', {
+    tableArn: 'arn:aws:dynamodb:us-east-1:xxxxxxxxxxxxx:table/existing-table',
+    tableStreamArn: 'arn:aws:dynamodb:us-east-1:xxxxxxxxxxxxx:table/existing-table/stream/2020-06-22T18:34:05.824'
+  });
+  const props: DynamoDBStreamToLambdaProps = {
+    lambdaFunctionProps: {
+      code: lambda.Code.fromAsset(`${__dirname}/lambda`),
+      runtime: lambda.Runtime.NODEJS_12_X,
+      handler: 'index.handler'
+    },
+    existingTableInterface
+  };
+
+  new DynamoDBStreamToLambda(stack, 'test-lambda-dynamodb-stack', props);
+
+  expect(stack).toHaveResource('AWS::Lambda::EventSourceMapping', {
+    EventSourceArn: "arn:aws:dynamodb:us-east-1:xxxxxxxxxxxxx:table/existing-table/stream/2020-06-22T18:34:05.824",
+  });
+
+  expect(stack).toHaveResource('AWS::IAM::Policy', {
+    PolicyDocument: {
+      Statement: [
+        {
+          Action: [
+            "xray:PutTraceSegments",
+            "xray:PutTelemetryRecords"
+          ],
+          Effect: "Allow",
+          Resource: "*"
+        },
+        {
+          Action: "dynamodb:ListStreams",
+          Effect: "Allow",
+          Resource: "*"
+        },
+        {
+          Action: [
+            "dynamodb:DescribeStream",
+            "dynamodb:GetRecords",
+            "dynamodb:GetShardIterator"
+          ],
+          Effect: "Allow",
+          Resource: "arn:aws:dynamodb:us-east-1:xxxxxxxxxxxxx:table/existing-table/stream/2020-06-22T18:34:05.824"
+        },
+        {
+          Action: [
+            "sqs:SendMessage",
+            "sqs:GetQueueAttributes",
+            "sqs:GetQueueUrl"
+          ],
+          Effect: "Allow",
+          Resource: {
+            "Fn::GetAtt": [
+              "testlambdadynamodbstackSqsDlqQueue4CC9868B",
+              "Arn"
+            ]
+          }
+        }
+      ],
+      Version: "2012-10-17"
+    }
+  });
+});