feat(iotevents): support setting Events on input and exit for State (#19249)

This PR allow states in IoT Events detector model to set event on input and exit.
This PR is in roadmap of #17711.
<img width="530" alt="スクリーンショット 2022-03-05 13 40 57" src="https://user-images.githubusercontent.com/11013683/156868196-a37f5926-05e2-4d3b-a881-17520b465518.png">


----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: yamatatsu

packages/@aws-cdk/aws-iotevents-actions/test/lambda/integ.lambda-invoke-action.expected.json

@@ -144,7 +144,6 @@
                   }
                 ]
               },
-              "OnInput": {},
               "StateName": "MyState"
             }
           ]

packages/@aws-cdk/aws-iotevents/README.md

@@ -64,10 +64,18 @@ const input = new iotevents.Input(this, 'MyInput', {
 const warmState = new iotevents.State({
   stateName: 'warm',
   onEnter: [{
-    eventName: 'test-event',
+    eventName: 'test-enter-event',
     condition: iotevents.Expression.currentInput(input),
     actions: [new actions.LambdaInvokeAction(func)], // optional
   }],
+  onInput: [{ // optional
+    eventName: 'test-input-event',
+    actions: [new actions.LambdaInvokeAction(func)],
+  }],
+  onExit: [{ // optional
+    eventName: 'test-exit-event',
+    actions: [new actions.LambdaInvokeAction(func)],
+  }],
 });
 const coldState = new iotevents.State({
   stateName: 'cold',

packages/@aws-cdk/aws-iotevents/lib/state.ts

@@ -66,12 +66,28 @@ export interface StateProps {
   readonly stateName: string;
 
   /**
-   * Specifies the events on enter. the conditions of the events are evaluated when the state is entered.
-   * If the condition is `TRUE`, the actions of the event are performed.
+   * Specifies the events on enter. The conditions of the events will be evaluated when entering this state.
+   * If the condition of the event evaluates to `true`, the actions of the event will be executed.
    *
-   * @default - events on enter will not be set
+   * @default - no events will trigger on entering this state
    */
   readonly onEnter?: Event[];
+
+  /**
+   * Specifies the events on input. The conditions of the events will be evaluated when any input is received.
+   * If the condition of the event evaluates to `true`, the actions of the event will be executed.
+   *
+   * @default - no events will trigger on input in this state
+   */
+  readonly onInput?: Event[];
+
+  /**
+   * Specifies the events on exit. The conditions of the events are evaluated when an exiting this state.
+   * If the condition evaluates to `true`, the actions of the event will be executed.
+   *
+   * @default - no events will trigger on exiting this state
+   */
+  readonly onExit?: Event[];
 }
 
 /**
@@ -141,12 +157,18 @@ export class State {
   }
 
   private toStateJson(scope: Construct, actionBindOptions: ActionBindOptions): CfnDetectorModel.StateProperty {
-    const { onEnter } = this.props;
+    const { onEnter, onInput, onExit } = this.props;
     return {
       stateName: this.stateName,
-      onEnter: onEnter && { events: toEventsJson(scope, actionBindOptions, onEnter) },
-      onInput: {
+      onEnter: onEnter && {
+        events: toEventsJson(scope, actionBindOptions, onEnter),
+      },
+      onInput: (onInput || this.transitionEvents.length !== 0) ? {
+        events: toEventsJson(scope, actionBindOptions, onInput),
         transitionEvents: toTransitionEventsJson(scope, actionBindOptions, this.transitionEvents),
+      } : undefined,
+      onExit: onExit && {
+        events: toEventsJson(scope, actionBindOptions, onExit),
       },
     };
   }
@@ -155,9 +177,9 @@ export class State {
 function toEventsJson(
   scope: Construct,
   actionBindOptions: ActionBindOptions,
-  events: Event[],
-): CfnDetectorModel.EventProperty[] {
-  return events.map(event => ({
+  events?: Event[],
+): CfnDetectorModel.EventProperty[] | undefined {
+  return events?.map(event => ({
     eventName: event.eventName,
     condition: event.condition?.evaluate(),
     actions: event.actions?.map(action => action.bind(scope, actionBindOptions).configuration),

packages/@aws-cdk/aws-iotevents/test/detector-model.test.ts

@@ -176,6 +176,26 @@ test('can set actions to events', () => {
   });
 });
 
+test.each([
+  ['onInput', { onInput: [{ eventName: 'test-eventName1' }] }, { OnInput: { Events: [{ EventName: 'test-eventName1' }] } }],
+  ['onExit', { onExit: [{ eventName: 'test-eventName1' }] }, { OnExit: { Events: [{ EventName: 'test-eventName1' }] } }],
+])('can set %s to State', (_, events, expected) => {
+  // WHEN
+  new iotevents.DetectorModel(stack, 'MyDetectorModel', {
+    initialState: new iotevents.State({
+      stateName: 'test-state',
+      onEnter: [{ eventName: 'test-eventName1', condition: iotevents.Expression.currentInput(input) }],
+      ...events,
+    }),
+  });
+
+  // THEN
+  Template.fromStack(stack).hasResourceProperties('AWS::IoTEvents::DetectorModel', {
+    DetectorModelDefinition: {
+      States: [Match.objectLike(expected)],
+    },
+  });
+});
 
 test('can set an action to multiple detector models', () => {
   // GIVEN an action

packages/@aws-cdk/aws-iotevents/test/integ.detector-model.expected.json

@@ -63,7 +63,43 @@
                   }
                 ]
               },
+              "OnExit": {
+                "Events": [
+                  {
+                    "Condition": {
+                      "Fn::Join": [
+                        "",
+                        [
+                          "$input.",
+                          {
+                            "Ref": "MyInput08947B23"
+                          },
+                          ".payload.temperature == 31.7"
+                        ]
+                      ]
+                    },
+                    "EventName": "test-exit-event"
+                  }
+                ]
+              },
               "OnInput": {
+                "Events": [
+                  {
+                    "Condition": {
+                      "Fn::Join": [
+                        "",
+                        [
+                          "$input.",
+                          {
+                            "Ref": "MyInput08947B23"
+                          },
+                          ".payload.temperature == 31.6"
+                        ]
+                      ]
+                    },
+                    "EventName": "test-input-event"
+                  }
+                ],
                 "TransitionEvents": [
                   {
                     "Condition": {

packages/@aws-cdk/aws-iotevents/test/integ.detector-model.ts

@@ -23,6 +23,20 @@ class TestStack extends cdk.Stack {
           ),
         ),
       }],
+      onInput: [{
+        eventName: 'test-input-event',
+        condition: iotevents.Expression.eq(
+          iotevents.Expression.inputAttribute(input, 'payload.temperature'),
+          iotevents.Expression.fromString('31.6'),
+        ),
+      }],
+      onExit: [{
+        eventName: 'test-exit-event',
+        condition: iotevents.Expression.eq(
+          iotevents.Expression.inputAttribute(input, 'payload.temperature'),
+          iotevents.Expression.fromString('31.7'),
+        ),
+      }],
     });
     const offlineState = new iotevents.State({
       stateName: 'offline',