cheaply dump ec2 info to csv

cheaply dump ec2 info to csv

import boto3
import csv

# define header row and start a row_list with the header present
header_row = ["account_id", "aws_region", "environment", "instance_id", "instance_name", "security_groups"]
row_list = [header_row]

regions = ["us-east-1", "us-west-2"]

# ---------------------------------------------------------------------------------------------------------------------
# DEFINE FUNCTIONS
# ---------------------------------------------------------------------------------------------------------------------
def get_ec2_sg_info(region, environment):
    """Get EC2 with Security Group info.

    >>> get_ec2_sg_info(region)
    """
    # Get account_id and region
    sts_client = boto3.client("sts")
    account_id = sts_client.get_caller_identity()["Account"]
    aws_region = region

    # Get EC2 info
    ec2client = boto3.client('ec2', region_name=region)
    response = ec2client.describe_instances()

    for reservation in response["Reservations"]:
        for instance in reservation["Instances"]:
            # start an empty list to hold info
            ec2_instance_info = []

            # append account_id, environment and region
            ec2_instance_info.append(account_id)
            ec2_instance_info.append(environment)
            ec2_instance_info.append(aws_region)

            # append instance_id
            ec2_instance_info.append(instance["InstanceId"])

            # append instance_name
            instancename = ''
            for tags in instance["Tags"]:
                # print(tags)
                if tags["Key"] == 'Name':
                    instancename = tags["Value"]

            ec2_instance_info.append(instancename)

            # append security_groups
            AttachedSecurityGroups = []
            for groups in instance["SecurityGroups"]:
                AttachedSecurityGroups.append(groups["GroupName"])
            ec2_instance_info.append(AttachedSecurityGroups)

            # add instance list to row list
            row_list.append(ec2_instance_info)

            # reset list for next instance
            ec2_instance_info = []

# ---------------------------------------------------------------------------------------------------------------------
# MAIN
# ---------------------------------------------------------------------------------------------------------------------
alias = boto3.client('iam').list_account_aliases()['AccountAliases'][0]

if "nonprod" in alias:
    aws_environment = "nonprod"
elif "prod" in alias:
    aws_environment = "prod"
else:
    aws_environment = "n/a"

get_ec2_sg_info("us-east-1", aws_environment)
get_ec2_sg_info("us-west-2", aws_environment)

# Write CSV
with open('aws_ec2_and_sgs.csv', 'a', newline='') as file:
    writer = csv.writer(file)
    writer.writerows(row_list)