Service Artem is running…

This script looks for an EBS in the region “eu-west-1” with a tag whose key is “Application” and the value is passed as an argument, creating a snapshot of this EBS. In the same way, it searches for a snapshot by tag and deletes everything except the last one.

An example of running to create a snapshot:

python3 main.py create artem-test-app

An example of running to delete old snapshots:

python3 main.py cleanup artem-test-app

main.py:

from __future__ import print_function
from datetime import datetime
import sys
import boto3
import botocore
import urllib.request

ec2 = boto3.client('ec2', region_name='eu-west-1')

def create_snapshot(app):
    print("Creating snapshot for " + str(app))
    # Get Instance ID
    instances_id = []
    response = ec2.describe_instances(
        Filters = [
            {
                'Name': 'tag:Application',
                'Values': [
                    app,
                ]
            },
            {
                'Name': 'instance-state-name',
                'Values': ['running']
            }
        ]
    )

    for reservation in response['Reservations']:
        for instance in reservation['Instances']:
            instances_id.append(instance['InstanceId'])

    # Get Volumes ID
    volumes_id = []
    for instance_id in instances_id:
        response = ec2.describe_instance_attribute(InstanceId = instance_id, Attribute = 'blockDeviceMapping')
        for BlockDeviceMappings in response['BlockDeviceMappings']:
            volumes_id.append(BlockDeviceMappings['Ebs']['VolumeId'])

    # Create Volume Snapshot
    for volume_id in volumes_id:
        date = datetime.now()
        response = ec2.create_snapshot(
            Description = app + " snapshot created by Jenkins at " + str(date),
            VolumeId = volume_id,
            TagSpecifications=[
                {
                    'ResourceType': 'snapshot',
                    'Tags': [
                        {
                            'Key': 'Name',
                            'Value': app + "-snapshot"
                        },
                    ]
                },
            ]
        )


        try:
            print("Waiting until snapshot will be created...")
            snapshot_id = response['SnapshotId']
            snapshot_complete_waiter = ec2.get_waiter('snapshot_completed')
            snapshot_complete_waiter.wait(SnapshotIds=[snapshot_id], WaiterConfig = { 'Delay': 30, 'MaxAttempts': 120})

        except botocore.exceptions.WaiterError as e:
                print(e)

def cleanup_snapshot(app):
    print("Clean up step.")
    print("Looking for all snapshots regarding " + str(app) + " application.")
    # Get snapshots
    response = ec2.describe_snapshots(
        Filters = [
            {
                'Name': 'tag:Name',
                'Values': [
                    app + "-snapshot",
                ]
            },
        ],
        OwnerIds = [
            'self',
        ]
    )

    sorted_snapshots = sorted(response['Snapshots'], key=lambda k: k['StartTime'])

    # Clean up snapshots and keep only the latest snapshot
    for snapshot in sorted_snapshots[:-1]:
        print("Deleting snapshot: " + str(snapshot['SnapshotId']))
        response = ec2.delete_snapshot(
            SnapshotId = snapshot['SnapshotId']
        )

def main():
    if sys.argv[1:] and sys.argv[2:]:
        action = sys.argv[1]
        app = sys.argv[2]
        if action == 'create':
            create_snapshot(app)
        elif action == 'cleanup':
            cleanup_snapshot(app)
        else:
            print("Wrong action: " + str(action))
    else:
        print("This script for create and cleanup snapshots")
        print("Usage  : python3 " + sys.argv[0] + " {create|cleanup} " + "{application_tag}")
        print("Example: python3 " + sys.argv[0] + " create " + "ebs-snapshot-check")

if __name__ == '__main__':
    main()