feat(stepfunctions-tasks): assign boolean value in DynamoDB from state input (Json path) (#9088)

It is now possible to map a boolean value from state input using a Json path.

function booleanFromJsonPath added to DynamoAttributeValue which accepts
a Json path

Closes #9007

Co-authored-by: Michael Wiles <michaelwiles@lumkani.com>
Co-authored-by: Shiv Lakshminarayan <shivlaks@amazon.com>

Author: 3 people

packages/@aws-cdk/aws-stepfunctions-tasks/lib/dynamodb/private/utils.ts

@@ -22,3 +22,9 @@ export function transformAttributeValueMap(attrMap?: { [key: string]: DynamoAttr
   }
   return attrMap ? transformedValue : undefined;
 }
+
+export function validateJsonPath(value: string) {
+  if (!value.startsWith('$')) {
+    throw new Error("Data JSON path values must either be exactly equal to '$' or start with '$.'");
+  }
+}

packages/@aws-cdk/aws-stepfunctions-tasks/lib/dynamodb/shared-types.ts

@@ -1,4 +1,4 @@
-import { transformAttributeValueMap } from './private/utils';
+import { transformAttributeValueMap, validateJsonPath } from './private/utils';
 
 /**
  * Determines the level of detail about provisioned throughput consumption that is returned.
@@ -205,9 +205,7 @@ export class DynamoAttributeValue {
    * @param value Json path that specifies state input to be used
    */
   public static mapFromJsonPath(value: string) {
-    if (!value.startsWith('$')) {
-      throw new Error("Data JSON path values must either be exactly equal to '$' or start with '$.'");
-    }
+    validateJsonPath(value);
     return new DynamoAttributeValue({ 'M.$': value });
   }
 
@@ -232,6 +230,17 @@ export class DynamoAttributeValue {
     return new DynamoAttributeValue({ BOOL: value });
   }
 
+  /**
+   * Sets an attribute of type Boolean from state input through Json path.
+   * For example:  "BOOL": true
+   *
+   * @param value Json path that specifies state input to be used
+   */
+  public static booleanFromJsonPath(value: string) {
+    validateJsonPath(value);
+    return new DynamoAttributeValue({ BOOL: value.toString() });
+  }
+
   /**
    * Represents the data for the attribute. Data can be
    * i.e. "S": "Hello"

packages/@aws-cdk/aws-stepfunctions-tasks/test/dynamodb/integ.call-dynamodb.expected.json

@@ -193,7 +193,7 @@
               {
                 "Ref": "AWS::Partition"
               },
-              ":states:::dynamodb:putItem\",\"Parameters\":{\"Item\":{\"MessageId\":{\"S\":\"1234\"},\"Text\":{\"S.$\":\"$.bar\"},\"TotalCount\":{\"N\":\"18\"}},\"TableName\":\"",
+              ":states:::dynamodb:putItem\",\"Parameters\":{\"Item\":{\"MessageId\":{\"S\":\"1234\"},\"Text\":{\"S.$\":\"$.bar\"},\"TotalCount\":{\"N\":\"18\"},\"Activated\":{\"BOOL.$\":\"$.foo\"}},\"TableName\":\"",
               {
                 "Ref": "Messages804FA4EB"
               },

packages/@aws-cdk/aws-stepfunctions-tasks/test/dynamodb/integ.call-dynamodb.ts

@@ -36,6 +36,7 @@ class CallDynamoDBStack extends cdk.Stack {
         MessageId: tasks.DynamoAttributeValue.fromString(MESSAGE_ID),
         Text: tasks.DynamoAttributeValue.fromString(sfn.JsonPath.stringAt('$.bar')),
         TotalCount: tasks.DynamoAttributeValue.fromNumber(firstNumber),
+        Activated: tasks.DynamoAttributeValue.booleanFromJsonPath(sfn.JsonPath.stringAt('$.foo')),
       },
       table,
     });

packages/@aws-cdk/aws-stepfunctions-tasks/test/dynamodb/put-item.test.ts

@@ -27,6 +27,7 @@ test('PutItem task', () => {
     expressionAttributeNames: { OTHER_KEY: '#OK' },
     expressionAttributeValues: {
       ':val': tasks.DynamoAttributeValue.numberFromString(sfn.JsonPath.stringAt('$.Item.TotalCount.N')),
+      ':bool': tasks.DynamoAttributeValue.booleanFromJsonPath(sfn.JsonPath.stringAt('$.Item.flag')),
     },
     returnConsumedCapacity: tasks.DynamoConsumedCapacity.TOTAL,
     returnItemCollectionMetrics: tasks.DynamoItemCollectionMetrics.SIZE,
@@ -56,7 +57,10 @@ test('PutItem task', () => {
       },
       ConditionExpression: 'ForumName <> :f and Subject <> :s',
       ExpressionAttributeNames: { OTHER_KEY: '#OK' },
-      ExpressionAttributeValues: { ':val': { 'N.$': '$.Item.TotalCount.N' } },
+      ExpressionAttributeValues: {
+        ':val': { 'N.$': '$.Item.TotalCount.N' },
+        ':bool': { 'BOOL.$': '$.Item.flag' },
+      },
       ReturnConsumedCapacity: 'TOTAL',
       ReturnItemCollectionMetrics: 'SIZE',
       ReturnValues: 'ALL_NEW',

packages/@aws-cdk/aws-stepfunctions-tasks/test/dynamodb/shared-types.test.ts

@@ -234,6 +234,33 @@ describe('DynamoAttributeValue', () => {
     });
   });
 
+
+  test('from invalid boolean with json path', () => {
+    // GIVEN
+    const m = 'invalid';
+
+    // WHEN / THEN
+    expect(() => {
+      tasks.DynamoAttributeValue.booleanFromJsonPath(m);
+    }).toThrow("Data JSON path values must either be exactly equal to '$' or start with '$.'");
+
+  });
+
+
+  test('from boolean with json path', () => {
+    // GIVEN
+    const m = '$.path';
+    // WHEN
+    const attribute = tasks.DynamoAttributeValue.booleanFromJsonPath(sfn.JsonPath.stringAt(m));
+
+    // THEN
+    expect(sfn.FieldUtils.renderObject(attribute)).toEqual({
+      attributeValue: {
+        'BOOL.$': m,
+      },
+    });
+  });
+
   test('from boolean', () => {
     // WHEN
     const attribute = tasks.DynamoAttributeValue.fromBoolean(true);