Day 9. Python Use Cases For DevOps

Python Use Cases

Python Boto3 program to retrieve secrets from parameter store and secrets manager.

AWS system parameter store helps store values, secure information such as passwords, database strings, Amazon Machine Image (AMI) code IDs while running.

 #Retrieve secrets from parameter store
 import json
 import boto3
 ssm = boto3.client('ssm', 'us-east-1')
 def get_parameters():
     response = ssm.get_parameters(
         Names=['My-Password'],WithDecryption=True
     )
     for parameter in response['Parameters']:
         return parameter['Value']
 value=get_parameters()
 print(value)

AWS Secrets Manager helps you manage, retrieve, and rotate database credentials, API keys, and other secrets throughout their lifecycles.

 #Retrieve secrets from secret manager
 import json
 import boto3
 def get_secret_value(name):
    session = boto3.session.Session()
    s3_client = session.client('secretsmanager')
    secret_id=name
    response =   s3_client.get_secret_value(SecretId=secret_id)
    return response  

 get_secret_value("")

Python script to fetch IPs of live servers in an autoscaling group.

 import json
 from logging import Logger
 from botocore.exceptions import ClientError
 import boto3

 class AutoScalingServers:
     def __init__(self):
         client = boto3.client('autoscaling')
         self.autoscaling_client=client

     def describe_group(self,group_name):
         try:
             response = self.autoscaling_client.describe_auto_scaling_groups(
                         AutoScalingGroupNames=[group_name])
         except ClientError as e:
             Logger.error("Couls not describe group")
         else:
             groups=response.get("AutoScalingGroups", [])
             return groups

 ec2= boto3.resource("ec2")
 ASG= AutoScalingServers()
 groups =ASG.describe_group("My_ASG")
 for asg in groups:
     print(asg["AutoScalingGroupName"])
     instances =[i for i in asg['Instances']]
     ec2_instances= ec2.instances.filter(Filters=[{}])
     for instance in ec2_instances:
         print(instance.id,instance.public_dns_name,instance.private_ip_address)

Python AWS Lambda function to stop running instances on weekends.

 import boto3
 region="us-east-1"
 instances=["first instance id","second instance id"]
 ec2= boto3.client('ec2',region_name=region)

 ec2.stop_instances(Instances=instances)
 print('stopped instances',str(instances))

Python script to take backups.

 import os
 import shutil
 import schedule
 import time
 import zipfile

 def doprocess(source_folder, target_zip):
     zipf = zipfile.ZipFile(target_zip, "w")
     for subdir, dirs, files in os.walk(source_folder):
         for file in files:
             print(os.path.join(subdir, file))
             zipf.write(os.path.join(subdir, file))
     print("Created ", target_zip)

 def backup(src, dst):    
     shutil.copy(src,destination)

 def schedule_backup():
     time = "07:26"  # schedule time in 24h format
     schedule.every().day.at(time).do(backup, destzip, destination)
     print(f"Backup scheduled for {time} every day")
     while True:
         schedule.run_pending()
         time.sleep(1)

 if __name__ == "__main__":
     source = "path/to/source/directory"
     destination = "path/to/destination/directory"
     schedule_backup()

Find SSL expiry date using python.

 from cryptography import x509
 import socket
 import ssl
 import sys
 import json

 hostname = "google.com"
 port="443"
 context = ssl.create_default_context()

 with socket.create_connection((hostname, port)) as sock:
     with context.wrap_socket(sock, server_hostname=hostname) as ssock:
         print(ssock.version())
         data =ssock.getpeercert(True)      
         # print(ssock.getpeercert())

 pem_data = ssl.DER_cert_to_PEM_cert(data)
 cert_data = x509.load_pem_x509_certificate(str.encode(pem_data))
 print (cert_data.not_valid_after_utc)

Day 9. Python Use Cases For DevOps

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Python Use Cases