feat(iot): add topic rule action for step functions state machine execution

packages/@aws-cdk/aws-iot-actions/README.md

@@ -33,6 +33,7 @@ Currently supported are:
 - Publish messages on SNS topics
 - Write messages into columns of DynamoDB
 - Put messages IoT Events input
+- Start the execution of a Step Functions state machine
 
 ## Republish a message to another MQTT topic
 
@@ -328,3 +329,30 @@ const topicRule = new iot.TopicRule(this, 'TopicRule', {
   ],
 });
 ```
+
+## Start the execution of a Step Functions state machine
+
+The code snippet below creates an AWS IoT Rule that starts the execution of a Step Functions state machine: 
+
+```ts
+import * as iam from '@aws-cdk/aws-iam';
+import * as sfn from '@aws-cdk/aws-stepfunctions';
+
+declare const role: iam.Role;
+
+const stateMachine = new sfn.StateMachine(this, 'StateMachine', {
+  definition: new sfn.Pass(this, 'StartPass'),
+});
+
+const topicRule = new iot.TopicRule(this, 'TopicRule', {
+  sql: iot.IotSql.fromStringAsVer20160323(
+    "SELECT * FROM 'device/+/data",
+  ),
+  actions: [
+    new actions.StepFunctionsAction(stateMachine, {
+      role: role, // optional property, defaults to a new role
+      executionNamePrefix: 'StateMachinePrefix', // optional property, defaults to nothing
+    }),
+  ],
+});
+```

packages/@aws-cdk/aws-iot-actions/lib/index.ts

@@ -11,3 +11,4 @@ export * from './lambda-function-action';
 export * from './s3-put-object-action';
 export * from './sqs-queue-action';
 export * from './sns-topic-action';
+export * from './step-functions-action';

packages/@aws-cdk/aws-iot-actions/lib/step-functions-action.ts

@@ -0,0 +1,62 @@
+import * as iam from '@aws-cdk/aws-iam';
+import * as iot from '@aws-cdk/aws-iot';
+import * as sfn from '@aws-cdk/aws-stepfunctions';
+import { CommonActionProps } from './common-action-props';
+import { singletonActionRole } from './private/role';
+
+/**
+ * Configuration properties of an action for Step Functions
+ */
+export interface StepFunctionsActionProps extends CommonActionProps {
+  /**
+   * Specifies which prefix to append to the state machine execution.
+   *
+   * @default - no prefix
+   */
+  readonly executionNamePrefix?: string;
+}
+
+/**
+ * The action to start the execution of a Step Functions state machine
+ */
+export class StepFunctionsAction implements iot.IAction {
+  private readonly role?: iam.IRole;
+  private readonly stateMachine: sfn.StateMachine;
+  private readonly executionNamePrefix?: string;
+
+  /**
+   * @param stateMachine The Step Functions state machine whose execution will be started.
+   * @param props Optional properties to not use default
+   */
+  constructor(
+    stateMachine: sfn.StateMachine,
+    props: StepFunctionsActionProps = {},
+  ) {
+    this.stateMachine = stateMachine;
+    this.role = props.role;
+    this.executionNamePrefix = props.executionNamePrefix;
+  }
+
+  /**
+   * @internal
+   */
+  _bind(topicRule: iot.ITopicRule): iot.ActionConfig {
+    const role = this.role ?? singletonActionRole(topicRule);
+    role.addToPrincipalPolicy(
+      new iam.PolicyStatement({
+        actions: ['states:StartExecution'],
+        resources: [this.stateMachine.stateMachineArn],
+      }),
+    );
+
+    return {
+      configuration: {
+        stepFunctions: {
+          roleArn: role.roleArn,
+          stateMachineName: this.stateMachine.stateMachineName,
+          executionNamePrefix: this.executionNamePrefix,
+        },
+      },
+    };
+  }
+}

packages/@aws-cdk/aws-iot-actions/package.json

@@ -100,6 +100,7 @@
     "@aws-cdk/aws-s3": "0.0.0",
     "@aws-cdk/aws-sns": "0.0.0",
     "@aws-cdk/aws-sqs": "0.0.0",
+    "@aws-cdk/aws-stepfunctions": "0.0.0",
     "@aws-cdk/core": "0.0.0",
     "case": "1.6.3",
     "constructs": "^10.0.0"
@@ -118,6 +119,7 @@
     "@aws-cdk/aws-s3": "0.0.0",
     "@aws-cdk/aws-sns": "0.0.0",
     "@aws-cdk/aws-sqs": "0.0.0",
+    "@aws-cdk/aws-stepfunctions": "0.0.0",
     "@aws-cdk/core": "0.0.0",
     "constructs": "^10.0.0"
   },
@@ -136,4 +138,4 @@
     "tag": "next"
   },
   "private": true
-}
+}

packages/@aws-cdk/aws-iot-actions/test/stepfunctions/integ.stepfunctions-action.ts

@@ -0,0 +1,25 @@
+import * as iot from '@aws-cdk/aws-iot';
+import * as sfn from '@aws-cdk/aws-stepfunctions';
+import * as cdk from '@aws-cdk/core';
+import * as actions from '../../lib';
+
+const app = new cdk.App();
+
+class TestStack extends cdk.Stack {
+  constructor(scope: cdk.App, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    const topicRule = new iot.TopicRule(this, 'TopicRule', {
+      sql: iot.IotSql.fromStringAsVer20160323("SELECT * FROM 'device/+/data'"),
+    });
+
+    const stateMachine = new sfn.StateMachine(this, 'StateMachine', {
+      definition: new sfn.Pass(this, 'StartPass'),
+    });
+
+    topicRule.addAction(new actions.StepFunctionsAction(stateMachine));
+  }
+}
+
+new TestStack(app, 'test-stack');
+app.synth();

packages/@aws-cdk/aws-iot-actions/test/stepfunctions/stepfunctions-action.integ.snapshot/IntegrationTestDefaultTestDeployAssertDDDAF29A.template.json

@@ -0,0 +1 @@
+{}

packages/@aws-cdk/aws-iot-actions/test/stepfunctions/stepfunctions-action.integ.snapshot/cdk.out

@@ -0,0 +1 @@
+{"version":"20.0.0"}

packages/@aws-cdk/aws-iot-actions/test/stepfunctions/stepfunctions-action.integ.snapshot/integ.json

@@ -0,0 +1,11 @@
+{
+  "version": "20.0.0",
+  "testCases": {
+    "IntegrationTest/DefaultTest": {
+      "stacks": [
+        "test-stack"
+      ],
+      "assertionStack": "IntegrationTest/DefaultTest/DeployAssert"
+    }
+  }
+}

packages/@aws-cdk/aws-iot-actions/test/stepfunctions/stepfunctions-action.integ.snapshot/manifest.json

@@ -0,0 +1,58 @@
+{
+  "version": "20.0.0",
+  "artifacts": {
+    "Tree": {
+      "type": "cdk:tree",
+      "properties": {
+        "file": "tree.json"
+      }
+    },
+    "test-stack": {
+      "type": "aws:cloudformation:stack",
+      "environment": "aws://unknown-account/unknown-region",
+      "properties": {
+        "templateFile": "test-stack.template.json",
+        "validateOnSynth": false
+      },
+      "metadata": {
+        "/test-stack/TopicRule/Resource": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "TopicRule40A4EA44"
+          }
+        ],
+        "/test-stack/TopicRule/TopicRuleActionRole/Resource": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "TopicRuleTopicRuleActionRole246C4F77"
+          }
+        ],
+        "/test-stack/TopicRule/TopicRuleActionRole/DefaultPolicy/Resource": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "TopicRuleTopicRuleActionRoleDefaultPolicy99ADD687"
+          }
+        ],
+        "/test-stack/StateMachine/Role/Resource": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "StateMachineRoleB840431D"
+          }
+        ],
+        "/test-stack/StateMachine/Resource": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "StateMachine2E01A3A5"
+          }
+        ],
+        "/test-stack/Service-principalMap": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "ServiceprincipalMap"
+          }
+        ]
+      },
+      "displayName": "test-stack"
+    }
+  }
+}

packages/@aws-cdk/aws-iot-actions/test/stepfunctions/stepfunctions-action.integ.snapshot/test-stack.assets.json

@@ -0,0 +1,19 @@
+{
+  "version": "20.0.0",
+  "files": {
+    "33ea9644d18ddb62bc89360ac3bad439c89f0f9665650f0548bd2f3106d02783": {
+      "source": {
+        "path": "test-stack.template.json",
+        "packaging": "file"
+      },
+      "destinations": {
+        "current_account-current_region": {
+          "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
+          "objectKey": "33ea9644d18ddb62bc89360ac3bad439c89f0f9665650f0548bd2f3106d02783.json",
+          "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
+        }
+      }
+    }
+  },
+  "dockerImages": {}
+}