feat(scheduler): flexible time windows

packages/@aws-cdk/aws-scheduler-alpha/README.md

@@ -23,7 +23,7 @@ of millions of tasks across many AWS services without provisioning or managing u
 2. **Targets**: A target is an API operation that EventBridge Scheduler calls on your behalf every time your schedule runs. EventBridge Scheduler
 supports two types of targets: templated targets and universal targets. Templated targets invoke common API operations across a core groups of 
 services. For example, EventBridge Scheduler supports templated targets for invoking AWS Lambda Function or starting execution of Step Function state
-machine. For API operations that are not supported by templated targets you can use customizeable universal targets. Universal targets support calling
+machine. For API operations that are not supported by templated targets you can use customizable universal targets. Universal targets support calling
 more than 6,000 API operations across over 270 AWS services.
 3. **Schedule Group**: A schedule group is an Amazon EventBridge Scheduler resource that you use to organize your schedules. Your AWS account comes
 with a default scheduler group. A new schedule will always be added to a scheduling group. If you do not provide a scheduling group to add to, it 
@@ -143,7 +143,7 @@ new Schedule(this, 'Schedule', {
 
 The `@aws-cdk/aws-scheduler-targets-alpha` module includes classes that implement the `IScheduleTarget` interface for
 various AWS services. EventBridge Scheduler supports two types of targets: templated targets invoke common API
-operations across a core groups of services, and customizeable universal targets that you can use to call more
+operations across a core groups of services, and customizable universal targets that you can use to call more
 than 6,000 operations across over 270 services. A list of supported targets can be found at `@aws-cdk/aws-scheduler-targets-alpha`. 
 
 ### Input 
@@ -227,6 +227,23 @@ const schedule = new Schedule(this, 'Schedule', {
 
 > Visit [Data protection in Amazon EventBridge Scheduler](https://docs.aws.amazon.com/scheduler/latest/UserGuide/data-protection.html) for more details.
 
+## Configuring flexible time windows
+
+You can configure flexible time windows by specifying the `flexibleTimeWindow` property.
+Flexible time windows is disabled by default.
+
+```ts
+declare const target: targets.LambdaInvoke;
+
+const schedule = new Schedule(this, 'Schedule', {
+    schedule: ScheduleExpression.rate(Duration.hours(12)),
+    target,
+    flexibleTimeWindow: FlexibleTimeWindowMode.flexible(Duration.hours(10)),
+});
+```
+
+> Visit [Configuring flexible time windows](https://docs.aws.amazon.com/scheduler/latest/UserGuide/managing-schedule-flexible-time-windows.html) for more details.
+
 ## Error-handling 
 
 You can configure how your schedule handles failures, when EventBridge Scheduler is unable to deliver an event

packages/@aws-cdk/aws-scheduler-alpha/lib/schedule.ts

@@ -59,6 +59,47 @@ export interface ScheduleTargetProps {
   readonly retryAttempts?: number;
 }
 
+/**
+ * A time window during which EventBridge Scheduler invokes the schedule.
+ */
+export class FlexibleTimeWindowMode {
+  /**
+   * FlexibleTimeWindow is disabled.
+   */
+  public static off(): FlexibleTimeWindowMode {
+    return new FlexibleTimeWindowMode('OFF');
+  }
+
+  /**
+   * FlexibleTimeWindow is enabled.
+   */
+  public static flexible(maximumWindowInMinutes: Duration): FlexibleTimeWindowMode {
+    if (maximumWindowInMinutes.toMinutes() < 1 || maximumWindowInMinutes.toMinutes() > 1440) {
+      throw new Error(`maximumWindowInMinutes must be between 1 and 1440, got ${maximumWindowInMinutes.toMinutes()}`);
+    }
+    return new FlexibleTimeWindowMode('FLEXIBLE', maximumWindowInMinutes);
+  }
+
+  /**
+   * Determines whether the schedule is invoked within a flexible time window.
+   */
+  public readonly mode: string;
+
+  /**
+   * The maximum time window during which the schedule can be invoked.
+   *
+   * Must be between 1 to 1440 minutes.
+   *
+   * @default - Required if mode is FLEXIBLE.
+   */
+  public readonly maximumWindowInMinutes?: Duration;
+
+  private constructor(mode: string, maximumWindowInMinutes?: Duration) {
+    this.mode = mode;
+    this.maximumWindowInMinutes = maximumWindowInMinutes;
+  }
+}
+
 /**
  * Construction properties for `Schedule`.
  */
@@ -104,6 +145,7 @@ export interface ScheduleProps {
 
   /**
    * Indicates whether the schedule is enabled.
+   *
    * @default true
    */
   readonly enabled?: boolean;
@@ -114,6 +156,15 @@ export interface ScheduleProps {
    * @default - All events in Scheduler are encrypted with a key that AWS owns and manages.
    */
   readonly key?: kms.IKey;
+
+  /**
+   * A time window during which EventBridge Scheduler invokes the schedule.
+   *
+   * @see https://docs.aws.amazon.com/scheduler/latest/UserGuide/managing-schedule-flexible-time-windows.html
+   *
+   * @default FlexibleTimeWindowMode.off()
+   */
+  readonly flexibleTimeWindow?: FlexibleTimeWindowMode;
 }
 
 /**
@@ -254,9 +305,14 @@ export class Schedule extends Resource implements ISchedule {
 
     this.retryPolicy = targetConfig.retryPolicy;
 
+    const flexibleTimeWindow = props.flexibleTimeWindow ?? FlexibleTimeWindowMode.off();
+
     const resource = new CfnSchedule(this, 'Resource', {
       name: this.physicalName,
-      flexibleTimeWindow: { mode: 'OFF' },
+      flexibleTimeWindow: {
+        mode: flexibleTimeWindow.mode,
+        maximumWindowInMinutes: flexibleTimeWindow.maximumWindowInMinutes?.toMinutes(),
+      },
       scheduleExpression: props.schedule.expressionString,
       scheduleExpressionTimezone: props.schedule.timeZone?.timezoneName,
       groupName: this.group?.groupName,

packages/@aws-cdk/aws-scheduler-alpha/rosetta/default.ts-fixture

@@ -8,7 +8,7 @@ import * as sqs from 'aws-cdk-lib/aws-sqs';
 import * as cloudwatch from 'aws-cdk-lib/aws-cloudwatch';
 import * as targets from '@aws-cdk/aws-scheduler-targets-alpha';
 import { App, Stack, TimeZone, Duration } from 'aws-cdk-lib';
-import { ScheduleExpression, ScheduleTargetInput, ContextAttribute, Group, Schedule } from '@aws-cdk/aws-scheduler-alpha';
+import { ScheduleExpression, ScheduleTargetInput, ContextAttribute, Group, Schedule, FlexibleTimeWindowMode } from '@aws-cdk/aws-scheduler-alpha';
 
 class Fixture extends cdk.Stack {
   constructor(scope: Construct, id: string) {

packages/@aws-cdk/aws-scheduler-alpha/test/integ.schedule.js.snapshot/aws-cdk-scheduler-schedule.template.json

@@ -348,6 +348,37 @@
      }
     }
    }
+  },
+  "UseFlexibleTimeWindowBF55D3ED": {
+   "Type": "AWS::Scheduler::Schedule",
+   "Properties": {
+    "FlexibleTimeWindow": {
+     "MaximumWindowInMinutes": 10,
+     "Mode": "FLEXIBLE"
+    },
+    "ScheduleExpression": "rate(12 hours)",
+    "ScheduleExpressionTimezone": "Etc/UTC",
+    "State": "ENABLED",
+    "Target": {
+     "Arn": {
+      "Fn::GetAtt": [
+       "Function76856677",
+       "Arn"
+      ]
+     },
+     "Input": "\"Input Text\"",
+     "RetryPolicy": {
+      "MaximumEventAgeInSeconds": 180,
+      "MaximumRetryAttempts": 3
+     },
+     "RoleArn": {
+      "Fn::GetAtt": [
+       "Role1ABCC5F0",
+       "Arn"
+      ]
+     }
+    }
+   }
   }
  },
  "Parameters": {

packages/@aws-cdk/aws-scheduler-alpha/test/integ.schedule.ts

@@ -90,6 +90,12 @@ new scheduler.Schedule(stack, 'CustomerKmsSchedule', {
   key,
 });
 
+new scheduler.Schedule(stack, 'UseFlexibleTimeWindow', {
+  schedule: expression,
+  target: target,
+  flexibleTimeWindow: scheduler.FlexibleTimeWindowMode.flexible(cdk.Duration.minutes(10)),
+});
+
 new IntegTest(app, 'integtest-schedule', {
   testCases: [stack],
 });