Schedule Google Compute Engine VM Instance to Start and Stop

Flow

Cloud Scheduler will send start/stop event at specific time via Pub/Sub
The Pub/Sub event will trigger a Cloud Function, where it will start/stop the vm instances via @google-cloud/compute library.

NOTE: Technically Cloud Scheduler could call Cloud Function directly without Pub/Sub, but anyone who figure out the Cloud Function url could start/stop the vm instances (or you need to take extra steps to secure the url)

Create Compute Engine VM instance

Goto https://console.cloud.google.com/compute/instances to create a vm instance for testing.

Click Create instance
Name: test-schedule
Region: us-west1
Machine configuration: e2-micro
Zone: us-west1-b
Expand the Management, security, disks, networking, sole tenancy section.
- Under Management, click Add label. Enter schedule for Key and test for Value.
Click Create

Create Cloud Function

Goto https://console.cloud.google.com/functions to create cloud functions to start/stop the vm instances

Create Start Function

Click Create Function
Function name: startInstancePubSub
Region: default
Trigger type: Cloud Pub/Sub
Select a Cloud Pub/Sub topic: select Create a topic....
- Topic ID: start-instance-event
- Click Create Topic
Click Save
Click Next
Runtime: Node.js 10
Entry point: startInstancePubSub
Select index.js and paste the following code.

const Compute = require('@google-cloud/compute');const compute = new Compute();/** * Starts Compute Engine instances. * * Expects a PubSub message with JSON-formatted event data containing the * following attributes: *  zone - the GCP zone the instances are located in. *  label - the label of instances to start. * * @param {!object} event Cloud Function PubSub message event. * @param {!object} callback Cloud Function PubSub callback indicating *  completion. */exports.startInstancePubSub = async (event, context, callback) => {  try {    const payload = _validatePayload(      JSON.parse(Buffer.from(event.data, 'base64').toString())    );    // get vm instanaces by labels/metadata rather than name    // more convinient to change vm metadata rather changing cloud functions code    const options = {filter: `labels.${payload.label}`};    const [vms] = await compute.getVMs(options);    let vmCount = 0;    await Promise.all(      vms.map(async (instance) => {        console.log(`instance=${instance.name}, zone=${instance.zone.id}`)        if (payload.zone === instance.zone.id) {          const [operation] = await compute            .zone(payload.zone)            .vm(instance.name)            .start();          vmCount += 1          // Operation pending          return operation.promise();        }      })    );    // Operation complete. Instance successfully started.    const message = `Successfully started ${vmCount} instance(s)`;    console.log(message);    callback(null, message);  } catch (err) {    console.log(err);    callback(err);  }};/** * Validates that a request payload contains the expected fields. * * @param {!object} payload the request payload to validate. * @return {!object} the payload object. */const _validatePayload = (payload) => {  if (!payload.zone) {    throw new Error(`Attribute 'zone' missing from payload`);  } else if (!payload.label) {    throw new Error(`Attribute 'label' missing from payload`);  }  return payload;};

Select package.json and paste the following.

{  "name": "cloud-functions-schedule-instance",  "version": "0.0.1",  "private": true,  "engines": {    "node": ">=10.0.0"  },  "dependencies": {    "@google-cloud/pubsub": "^0.18.0",    "@google-cloud/compute": "^2.0.0"  }}

Click Deploy

Create Stop Function

Click Create Function
Function name: stopInstancePubSub
Region: default
Trigger type: Cloud Pub/Sub
Select a Cloud Pub/Sub topic: select Create a topic....
- Topic ID: stop-instance-event
- Click Create Topic
Click Save
Click Next
Runtime: Node.js 10
Entry point: stopInstancePubSub
Select index.js and paste the following code.

const Compute = require('@google-cloud/compute');const compute = new Compute();/** * Stops Compute Engine instances. * * Expects a PubSub message with JSON-formatted event data containing the * following attributes: *  zone - the GCP zone the instances are located in. *  label - the label of instances to stop. * * @param {!object} event Cloud Function PubSub message event. * @param {!object} callback Cloud Function PubSub callback indicating completion. */exports.stopInstancePubSub = async (event, context, callback) => {  try {    const payload = _validatePayload(      JSON.parse(Buffer.from(event.data, 'base64').toString())    );    // get vm instanaces by labels/metadata rather than name    // more convinient to change vm metadata rather changing cloud functions code    const options = {filter: `labels.${payload.label}`};    const [vms] = await compute.getVMs(options);    let vmCount = 0;    await Promise.all(      vms.map(async (instance) => {        console.log(`instance=${instance.name}, zone=${instance.zone.id}`)        if (payload.zone === instance.zone.id) {          const [operation] = await compute            .zone(payload.zone)            .vm(instance.name)            .stop();          vmCount += 1          // Operation pending          return operation.promise();        } else {          return Promise.resolve();        }      })    );    // Operation complete. Instance successfully stopped.    const message = `Successfully stopped ${vmCount} instance(s)`;    console.log(message);    callback(null, message);  } catch (err) {    console.log(err);    callback(err);  }};/** * Validates that a request payload contains the expected fields. * * @param {!object} payload the request payload to validate. * @return {!object} the payload object. */const _validatePayload = (payload) => {  if (!payload.zone) {    throw new Error(`Attribute 'zone' missing from payload`);  } else if (!payload.label) {    throw new Error(`Attribute 'label' missing from payload`);  }  return payload;};

Select package.json and paste the following.

{  "name": "cloud-functions-schedule-instance",  "version": "0.0.1",  "private": true,  "engines": {    "node": ">=10.0.0"  },  "dependencies": {    "@google-cloud/pubsub": "^0.18.0",    "@google-cloud/compute": "^2.0.0"  }}

Test the function

Goto https://console.cloud.google.com/functions
Click on stopInstancePubSub.
Click on Testing tab.
Triggering event:

{"data":"eyJ6b25lIjoidXMtd2VzdDEtYiIsICJsYWJlbCI6InNjaGVkdWxlPXRlc3QifQ=="}

NOTE: The above data is base64-encoded string for {"zone":"us-west1-b", "label":"schedule=test"}. If you use a different zone (for compute engine) or different labels/metadata, use an online base64 encoding tool to replace the string.

Click Test the function.
You should see Successfully stopped 1 instance(s) in the output.
Goto https://console.cloud.google.com/compute/instances to check if the instances are stopped.
You might want to verify if the instance have the right labels. Check the instance, click Show Info Panel and Click Labels.

Setup Cloud Scheduler

Goto https://console.cloud.google.com/cloudscheduler

Create Start Job

Click Create Job.
Region: default
Click Next
Name: startup-instances
Frequency: 0 9 * * 1-5 (9am, Mon-Fri)
Timezone: up to you
Target: Pub/Sub
Topic: start-instance-event
Payload: {"zone":"us-west1-b","label":"schedule=test"}
Click Create

Create Stop Job

Click Create Job.
Region: default
Click Next
Name: shutdown-instances
Frequency: 0 17 * * 1-5 (5pm, Mon-Fri)
Timezone: up to you
Target: Pub/Sub
Topic: stop-instance-event
Payload: {"zone":"us-west1-b","label":"schedule=test"}
Click Create

Test Scheduler

Click Run now to test startup-instances or shutdown-instances.

VM Startup Script

You might want to configure Auto Start Python Script on Boot

References:

https://cloud.google.com/scheduler/docs/start-and-stop-compute-engine-instances-on-a-schedule