address comments

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

@@ -58,7 +58,7 @@ const warmState = new iotevents.State({
   stateName: 'warm',
   onEnter: [{
     eventName: 'test-event',
-    when: iotevents.Expression.currentInput(input),
+    condition: iotevents.Expression.currentInput(input),
   }],
 });
 const coldState = new iotevents.State({

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

@@ -10,10 +10,9 @@ export interface Event {
   readonly eventName: string;
 
   /**
-   * The condition that is used to determine to cause the actions.
-   * When this was evaluated to TRUE, the actions are triggered.
+   * The Boolean expression that, when TRUE, causes the actions to be performed.
    *
    * @default - none (the actions are always executed)
    */
-  readonly when?: Expression;
+  readonly condition?: Expression;
 }

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

@@ -30,10 +30,9 @@ interface TransitionEvent {
   readonly eventName: string;
 
   /**
-   * The condition that is used to determine to cause the state transition and the actions.
-   * When this was evaluated to TRUE, the state transition and the actions are triggered.
+   * The Boolean expression that, when TRUE, causes the state transition and the actions to be performed.
    */
-  readonly when: Expression;
+  readonly condition: Expression;
 
   /**
    * The next state to transit to. When the resuld of condition expression is TRUE, the state is transited.
@@ -82,15 +81,15 @@ export class State {
    * @param options transition options including the condition that causes the state transition
    */
   public transitionTo(targetState: State, options: TransitionOptions) {
-    const alreadyAdded = this.transitionEvents.some((event) => event.nextState === targetState);
+    const alreadyAdded = this.transitionEvents.some(transitionEvent => transitionEvent.nextState === targetState);
     if (alreadyAdded) {
       throw new Error(`State '${this.stateName}' already has a transition defined to '${targetState.stateName}'`);
     }
 
     this.transitionEvents.push({
       eventName: options.eventName ?? `${this.stateName}_to_${targetState.stateName}`,
       nextState: targetState,
-      when: options.when,
+      condition: options.when,
     });
   }
 
@@ -116,12 +115,12 @@ export class State {
   }
 
   /**
-   * Returns true if this state has at least one condition as `Event.when`s.
+   * Returns true if this state has at least one condition via events.
    *
    * @internal
    */
   public _onEnterEventsHaveAtLeastOneCondition(): boolean {
-    return this.props.onEnter?.some(event => event.when) ?? false;
+    return this.props.onEnter?.some(event => event.condition) ?? false;
   }
 
   private toStateJson(): CfnDetectorModel.StateProperty {
@@ -137,24 +136,20 @@ export class State {
 }
 
 function toEventsJson(events: Event[]): CfnDetectorModel.EventProperty[] {
-  return events.map(event => {
-    return {
-      eventName: event.eventName,
-      condition: event.when?.evaluate(),
-    };
-  });
+  return events.map(event => ({
+    eventName: event.eventName,
+    condition: event.condition?.evaluate(),
+  }));
 }
 
 function toTransitionEventsJson(transitionEvents: TransitionEvent[]): CfnDetectorModel.TransitionEventProperty[] | undefined {
   if (transitionEvents.length === 0) {
     return undefined;
   }
 
-  return transitionEvents.map(transitionEvent => {
-    return {
-      eventName: transitionEvent.eventName,
-      condition: transitionEvent.when.evaluate(),
-      nextState: transitionEvent.nextState.stateName,
-    };
-  });
+  return transitionEvents.map(transitionEvent => ({
+    eventName: transitionEvent.eventName,
+    condition: transitionEvent.condition.evaluate(),
+    nextState: transitionEvent.nextState.stateName,
+  }));
 }

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

@@ -17,7 +17,7 @@ test('Default property', () => {
       stateName: 'test-state',
       onEnter: [{
         eventName: 'test-eventName',
-        when: iotevents.Expression.fromString('test-eventCondition'),
+        condition: iotevents.Expression.fromString('test-eventCondition'),
       }],
     }),
   });
@@ -59,7 +59,7 @@ test('can get detector model name', () => {
       stateName: 'test-state',
       onEnter: [{
         eventName: 'test-eventName',
-        when: iotevents.Expression.fromString('test-eventCondition'),
+        condition: iotevents.Expression.fromString('test-eventCondition'),
       }],
     }),
   });
@@ -91,7 +91,7 @@ test.each([
       stateName: 'test-state',
       onEnter: [{
         eventName: 'test-eventName',
-        when: iotevents.Expression.fromString('test-eventCondition'),
+        condition: iotevents.Expression.fromString('test-eventCondition'),
       }],
     }),
   });
@@ -108,7 +108,7 @@ test('can set multiple events to State', () => {
       onEnter: [
         {
           eventName: 'test-eventName1',
-          when: iotevents.Expression.fromString('test-eventCondition'),
+          condition: iotevents.Expression.fromString('test-eventCondition'),
         },
         {
           eventName: 'test-eventName2',
@@ -145,7 +145,7 @@ test('can set states with transitions', () => {
     stateName: 'firstState',
     onEnter: [{
       eventName: 'test-eventName',
-      when: iotevents.Expression.currentInput(input),
+      condition: iotevents.Expression.currentInput(input),
     }],
   });
   const secondState = new iotevents.State({
@@ -231,7 +231,7 @@ test('can set role', () => {
       stateName: 'test-state',
       onEnter: [{
         eventName: 'test-eventName',
-        when: iotevents.Expression.fromString('test-eventCondition'),
+        condition: iotevents.Expression.fromString('test-eventCondition'),
       }],
     }),
   });
@@ -312,7 +312,7 @@ describe('Expression', () => {
         stateName: 'test-state',
         onEnter: [{
           eventName: 'test-eventName',
-          when: iotevents.Expression.currentInput(input),
+          condition: iotevents.Expression.currentInput(input),
         }],
       }),
     });
@@ -340,7 +340,7 @@ describe('Expression', () => {
         stateName: 'test-state',
         onEnter: [{
           eventName: 'test-eventName',
-          when: iotevents.Expression.inputAttribute(input, 'json.path'),
+          condition: iotevents.Expression.inputAttribute(input, 'json.path'),
         }],
       }),
     });
@@ -368,7 +368,7 @@ describe('Expression', () => {
         stateName: 'test-state',
         onEnter: [{
           eventName: 'test-eventName',
-          when: iotevents.Expression.eq(
+          condition: iotevents.Expression.eq(
             iotevents.Expression.fromString('"aaa"'),
             iotevents.Expression.fromString('"bbb"'),
           ),
@@ -399,7 +399,7 @@ describe('Expression', () => {
         stateName: 'test-state',
         onEnter: [{
           eventName: 'test-eventName',
-          when: iotevents.Expression.and(
+          condition: iotevents.Expression.and(
             iotevents.Expression.fromString('true'),
             iotevents.Expression.fromString('false'),
           ),

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

@@ -14,8 +14,8 @@ class TestStack extends cdk.Stack {
       stateName: 'online',
       onEnter: [{
         eventName: 'test-event',
-        // meaning `when: 'currentInput("test_input") && $input.test_input.payload.temperature == 31.5'`
-        when: iotevents.Expression.and(
+        // meaning `condition: 'currentInput("test_input") && $input.test_input.payload.temperature == 31.5'`
+        condition: iotevents.Expression.and(
           iotevents.Expression.currentInput(input),
           iotevents.Expression.eq(
             iotevents.Expression.inputAttribute(input, 'payload.temperature'),