Use an existing tag on AWS EC2 instance/s to add/delete new/old tags

ec2-instance-tagger.py

#!/usr/bin/env python3

#
# Use an existing tag on AWS EC2 instance/s to add/delete new/old tags.
#
# Usage: ./ec2-instance-tagger.py <aws-profile> <aws-region> <existing-tag-key> <existing-tag-value> <target-tag-key> <target-tag-value> <action>
#
# I've 3 EC2 instances already tagged with Temp:True , adding new tag Zone:2
# ./ec2-instance-tagger.py myawsprofile us-east-1 Temp True Zone 2 add
# Expected output:
#+---------------------+------+-------+--------+
#|          ID         | TAG  | VALUE | ACTION |
#+---------------------+------+-------+--------+
#| i-0559c5798de2c.... | Zone |   2   |  add   |
#| i-01c4a3c613c90.... | Zone |   2   |  add   |
#| i-067e9b541d01e.... | Zone |   2   |  add   |
#+---------------------+------+-------+--------+
#
# I've 3 EC2 instances already tagged with Temp:True , deleting Zone:2 tag
# ./ec2-instance-tagger.py myawsprofile us-east-1 Temp True Zone 2 delete
# Expected output:
#+---------------------+------+-------+--------+
#|          ID         | TAG  | VALUE | ACTION |
#+---------------------+------+-------+--------+
#| i-0559c5798de2c.... | Zone |   2   | delete |
#| i-01c4a3c613c90.... | Zone |   2   | delete |
#| i-067e9b541d01e.... | Zone |   2   | delete |
#+---------------------+------+-------+--------+

import boto3
import sys
from botocore.exceptions import ClientError
from prettytable import PrettyTable


def connect_aws(vProfile, vRegion, vService):
    try:
        boto3.setup_default_session(profile_name=vProfile, region_name=vRegion)
        worker = boto3.client(vService)
        return worker
    except ClientError as e:
        print(e)


def check_args():
    if len(sys.argv) < 7:
        print(
            f'Usage: {sys.argv[0]} aws-profile aws-region existing-tag-key existing-tag-value target-tag-key target-tag-value action')
        exit()


def ec2_add_tag(vWorker, vInstanceId, vTargetTagKey, vTargetTagValue):
    try:
        response = vWorker.create_tags(Resources=[vInstanceId, ], Tags=[
            {'Key': vTargetTagKey, 'Value': vTargetTagValue, }, ], )
    except ClientError as e:
        print(e)
    return response


def ec2_delete_tag(vWorker, vInstanceId, vTargetTagKey, vTargetTagValue):
    try:
        response = vWorker.delete_tags(Resources=[vInstanceId, ], Tags=[
            {'Key': vTargetTagKey, 'Value': vTargetTagValue, }, ], )
    except ClientError as e:
        print(e)
    return response


def ec2_tagger(vWorker, vAction):
    # Pretty Table prepare
    vCuteTable = PrettyTable()
    # Empty List
    vWorkerList = []
    # Get Instance List
    try:
        response = vWorker.describe_instances(
            Filters=[{'Name': 'instance-state-name', 'Values': ['running', 'stopped']}, ])
    except ClientError as e:
        print(e)

    if vAction.lower() == 'list':
        for reservation in response["Reservations"]:
            for instance in reservation["Instances"]:
                vIdHolder = instance["InstanceId"]
                for item in instance["Tags"]:
                    if item['Key'] == gExistingTagKey and item['Value'] == gExistingTagValue:
                        vWorkerList.append(
                            (vIdHolder, item['Key'], item['Value'], vAction.lower()))
    elif vAction.lower() == 'add':
        for reservation in response["Reservations"]:
            for instance in reservation["Instances"]:
                vIdHolder = instance["InstanceId"]
                for item in instance["Tags"]:
                    if item['Key'] == gExistingTagKey and item['Value'] == gExistingTagValue:
                        ec2_add_tag(
                            vWorker, vIdHolder, gTargetTagKey, gTargetTagValue)
                        vWorkerList.append(
                            (vIdHolder, gTargetTagKey, gTargetTagValue, vAction.lower()))
    elif vAction.lower() == 'delete':
        for reservation in response["Reservations"]:
            for instance in reservation["Instances"]:
                vIdHolder = instance["InstanceId"]
                for item in instance["Tags"]:
                    if item['Key'] == gExistingTagKey and item['Value'] == gExistingTagValue:
                        ec2_delete_tag(
                            vWorker, vIdHolder, gTargetTagKey, gTargetTagValue)
                        vWorkerList.append(
                            (vIdHolder, gTargetTagKey, gTargetTagValue, vAction.lower()))
    else:
        print(f'I do not know what to do !!!')
        exit()

    vCuteTable.field_names = ["ID", "TAG", "VALUE", "ACTION"]
    for item in vWorkerList:
        vCuteTable.add_row([item[0], item[1], item[2], item[3]])
    return vCuteTable

#
# MAIN STARTS HERE
#
if __name__ == '__main__':
    # Check number of arguments
    check_args()
    # Set vars
    gProfile = sys.argv[1]
    gRegion = sys.argv[2]
    gExistingTagKey = sys.argv[3]
    gExistingTagValue = sys.argv[4]
    gTargetTagKey = sys.argv[5]
    gTargetTagValue = sys.argv[6]
    gAction = sys.argv[7]
    # Connect to AWS
    worker_ec2 = connect_aws(gProfile, gRegion, 'ec2')
    result = ec2_tagger(worker_ec2, gAction)
    print(result)