AWS EC2 Instance Running Scheduler

AWS CDK construct that starts and stops EC2 instances on a cron schedule using EventBridge Scheduler and a Durable Execution Lambda. The handler discovers instances with the Resource Groups Tagging API, runs start/stop and polls until the instance reaches the target state (durable step / wait), processes multiple instances in parallel (bounded concurrency), and posts Slack summary and per-instance thread messages using a secret from Secrets Manager. The Lambda emits structured application logs (invocation, EC2 transitions, Slack steps, completion) alongside JSON platform logs.

Features

• Tag-based targeting – Select EC2 instances by tag key and values (e.g. Schedule / YES) via tag:GetResources.
• EventBridge Scheduler – Separate cron rules for start and stop, with per-rule timezone (aws-cdk-lib TimeZone).
• Durable Lambda – One Lambda with AWS Lambda Durable Execution (step, wait, map, child contexts per instance) for long-running workflows without Step Functions.
• Stable-state polling – After start/stop, the function waits and re-describes instances until running (start mode) or stopped (stop mode), or until a terminal error.
• Slack notifications – Required for a successful run: parent message plus threaded updates per instance; credentials come from Secrets Manager (token and channel JSON). The secret name is passed as SLACK_SECRET_NAME on the function (from secrets.slackSecretName) and validated at runtime via safe-env-getter.
• Structured logging – The handler uses the durable execution ctx.logger for traceable JSON application logs (e.g. invocation, describe/start/stop/wait loops, target count, Slack posts, errors before instance state failures).
• Scheduling toggle – Enable or disable both schedules without removing the stack (enableScheduling).
• Configurable schedules – Optional cron overrides for start and stop (minute, hour, week, timezone); sensible defaults if omitted.
• IAM and observability – EC2 and tagging API permissions, Slack secret read grant, Parameters and Secrets Lambda Extension (configured on the function for secret access patterns), JSON logging with configurable system/application levels, and a dedicated log group (construct defaults).

Installation

npm

npm install aws-ec2-instance-running-scheduler

yarn

yarn add aws-ec2-instance-running-scheduler

pnpm

pnpm add aws-ec2-instance-running-scheduler

Usage

Use the construct EC2InstanceRunningScheduler when embedding the scheduler in an existing stack or other CDK scope.

import * as cdk from 'aws-cdk-lib';
import { TimeZone } from 'aws-cdk-lib';
import { EC2InstanceRunningScheduler } from 'aws-ec2-instance-running-scheduler';

const app = new cdk.App();
const stack = new cdk.Stack(app, 'MyStack');

new EC2InstanceRunningScheduler(stack, 'EC2InstanceRunningScheduler', {
  targetResource: {
    tagKey: 'Schedule',
    tagValues: ['YES'],
  },
  secrets: {
    slackSecretName: 'my-slack-secret',
  },
  startSchedule: {
    timezone: TimeZone.ASIA_TOKYO,
    minute: '55',
    hour: '8',
    week: 'MON-FRI',
  },
  stopSchedule: {
    timezone: TimeZone.ASIA_TOKYO,
    minute: '5',
    hour: '19',
    week: 'MON-FRI',
  },
  enableScheduling: true,
});

Use the stack EC2InstanceRunningScheduleStack when deploying the scheduler as its own stack. It accepts the same scheduler options as the construct (plus standard StackProps such as env).

import * as cdk from 'aws-cdk-lib';
import { TimeZone } from 'aws-cdk-lib';
import { EC2InstanceRunningScheduleStack } from 'aws-ec2-instance-running-scheduler';

const app = new cdk.App();

new EC2InstanceRunningScheduleStack(app, 'EC2InstanceRunningScheduleStack', {
  targetResource: {
    tagKey: 'Schedule',
    tagValues: ['YES'],
  },
  secrets: {
    slackSecretName: 'my-slack-secret',
  },
  startSchedule: {
    timezone: TimeZone.ASIA_TOKYO,
    minute: '55',
    hour: '8',
    week: 'MON-FRI',
  },
  stopSchedule: {
    timezone: TimeZone.ASIA_TOKYO,
    minute: '5',
    hour: '19',
    week: 'MON-FRI',
  },
  enableScheduling: true,
});

EventBridge Scheduler invokes the Lambda with Params.TagKey, Params.TagValues, and Params.Mode (Start or Stop); the construct wires this for you. The function environment includes SLACK_SECRET_NAME set to secrets.slackSecretName.

Options

These options apply to EC2InstanceRunningScheduler and to EC2InstanceRunningScheduleStack (stack props include them alongside StackProps).

| Option | Type | Required | Description | |--------|------|----------|-------------| | targetResource | TargetResource | Yes | Tag key and values used to select EC2 instances. | | secrets | Secrets | Yes | Identifies the Secrets Manager secret used for Slack (slackSecretName). | | startSchedule | Schedule | No | Cron for starting instances (default: 50 7 ? * MON-FRI * in Etc/UTC). | | stopSchedule | Schedule | No | Cron for stopping instances (default: 5 19 ? * MON-FRI * in Etc/UTC). | | enableScheduling | boolean | No | Whether both scheduler rules are enabled (default: true). |

TargetResource

• tagKey – Tag key used to select instances (e.g. Schedule).
• tagValues – Tag values that must match (e.g. ['YES']).

Schedule

• timezone – TimeZone from aws-cdk-lib (e.g. TimeZone.ASIA_TOKYO, TimeZone.ETC_UTC).
• minute – Cron minute (0–59).
• hour – Cron hour (0–23).
• week – Cron day-of-week field (e.g. MON-FRI).

Secrets

• slackSecretName – Name of the AWS Secrets Manager secret. The Lambda expects JSON with token (Slack bot token) and channel (channel ID or name for chat.postMessage). The construct sets SLACK_SECRET_NAME on the function to this value; the handler reads and validates it at runtime (via safe-env-getter).

Requirements

• Node.js ≥ 20.0.0 (for developing or synthesizing CDK apps that depend on this package).
• aws-cdk-lib ^2.232.0 and constructs ^10.5.1 (peer dependencies).
• AWS – EventBridge Scheduler; Lambda with Durable Execution (requires Node.js 22+ in the deployment region—runtime is the latest Node.js available in the region per the construct), a live alias, Parameters and Secrets Lambda Extension; EC2 (describe/start/stop); Resource Groups Tagging API; Secrets Manager. The deployed function uses arm64, Durable Execution–compatible IAM and settings, and a bundled handler that loads secrets via aws-lambda-secret-fetcher.

License

This project is licensed under the Apache-2.0 License.