I have the same use case on my project, and I use this python function in order to start and stop a vm, my function can handle the paths start and stop
from flask import Flask, request, abort
import os
import logging
app = Flask(__name__)
@app.route('/')
@app.route('/<path:path>')
def power(path=None):
#this libraries are mandatory to reach compute engine api
from googleapiclient import discovery
from oauth2client.client import GoogleCredentials
#the function will take the service account of your function
credentials = GoogleCredentials.get_application_default()
#this line is to specify the api that we gonna use, in this case compute engine
service = discovery.build('compute', 'v1', credentials=credentials, cache_discovery=False)
logging.getLogger('googleapiclient.discovery_cache').setLevel(logging.ERROR)
# Project ID for this request.
project = yourprojectID # Update placeholder value.
zone = request.args.get('zone', None)
instance = request.args.get('instance', None)
#call the method to start or stop the instance
if (request.path == "/stop"):
req = service.instances().stop(project=project, zone=zone, instance=instance)
elif (request.path == "/start"):
req = service.instances().start(project=project, zone=zone, instance=instance)
else:
abort(418)
#execute the command
response = req.execute()
print(response)
return ("OK")
if __name__ == '__main__':
app.run(port=3000, debug=True)
requirements.txt file
google-api-python-client
oauth2client
flask
Scheduler config
- Create a service account with functions.invoker permission within your function
- Create new Cloud scheduler job
- Specify the frequency in cron format.
- Specify HTTP as the target type.
- Add the URL of your cloud function and method as always.
- Select the token OIDC from the Auth header dropdown
- Add the service account email in the Service account text box.
- In
audience field you must only need to write the URL of the function without any additional parameter
On cloud scheduler, I hit my function by using these URLs
https://us-central1-yourprojectID.cloudfunctions.net/power/stop?zone=us-central1-a&instance=instance-1
https://us-central1-yourprojectID.cloudfunctions.net/power/stop?zone=us-central1-a&instance=instance-1
and I used this audience
https://us-central1-yourprojectID.cloudfunctions.net/power
please replace yourprojectID in the code and in the URLs
us-central1 is the region where my function is located, power is the name of my function, us-central1-a is the zone where my instance is located and instance-1 is the name of my instance
update for java
Cloud functions supports java11 and maven but this is on beta
first you need this dependencies, please add the following lines to your pom.xml file:
<dependency>
<groupId>com.google.apis</groupId>
<artifactId>google-api-services-compute</artifactId>
<version>beta-rev20200629-1.30.10</version>
</dependency>
<dependency>
<groupId>com.google.api-client</groupId>
<artifactId>google-api-client</artifactId>
<version>1.30.10</version>
</dependency>
Cloud function to START a VM
package com.example;
import com.google.cloud.functions.HttpFunction;
import com.google.cloud.functions.HttpRequest;
import com.google.cloud.functions.HttpResponse;
import java.io.BufferedWriter;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.services.compute.Compute;
import com.google.api.services.compute.model.Operation;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.util.Arrays;
public class Example implements HttpFunction {
@Override
public void service(HttpRequest request, HttpResponse response) throws Exception, IOException, GeneralSecurityException {
// Project ID for this request.
String project = "my-project"; // TODO: Update placeholder value.
// The name of the zone for this request.
String zone = "my-zone"; // TODO: Update placeholder value.
// Name of the instance resource to start.
String instance = "my-instance"; // TODO: Update placeholder value.
Compute computeService = createComputeService();
// you can change the method start to stop
Compute.Instances.Start request = computeService.instances().start(project, zone, instance);
Operation xresponse = xrequest.execute();
// TODO: Change code below to process the `response` object:
System.out.println(xresponse);
BufferedWriter writer = response.getWriter();
writer.write("Done");
}
public static Compute createComputeService() throws IOException, GeneralSecurityException {
HttpTransport httpTransport = GoogleNetHttpTransport.newTrustedTransport();
JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
GoogleCredential credential = GoogleCredential.getApplicationDefault();
if (credential.createScopedRequired()) {
credential =
credential.createScoped(Arrays.asList("https://www.googleapis.com/auth/cloud-platform"));
}
return new Compute.Builder(httpTransport, jsonFactory, credential)
.setApplicationName("Google-ComputeSample/0.1")
.build();
}
}
For more information you can check this document in this document are some examples in different programming languages
