boto3_create_ec2_example.py

# needs Python3, though easily adapted

from __future__ import unicode_literals
import boto3

def main():
    session = boto3.session.Session(profile_name='aws_credentials_profile')
    ec2 = session.resource('ec2')

    # define instance parameters
    # type
    image_id = get_amazon_linux_ami()
    instance_type = 't2.nano'
    # network
    security_group_ids = ['sg-abcde123']
    subnet_id = 'subnet-abcde123' # bogdan_private 1a
    network_interfaces = [
        {
            'DeviceIndex': 0,
            'SubnetId': subnet_id,
            'Groups': security_group_ids,
            'AssociatePublicIpAddress': False
        }
    ]
    # storage
    block_device_mappings = [
        {
            'DeviceName': get_root_device_name(image_id),
            'Ebs': { 
                'VolumeSize': 8,
                'DeleteOnTermination': True,
                'VolumeType': 'gp2',
            },
        },
    ]
    ebs_optimized = False # TODO: maybe it can be determined from instance type?
    # access
    ssh_key_name = 'add-one-or-lose-access'
    iam_instance_profile='' # role
    #user_data = get_user_data('script_to_run_on_first_boot.sh')
    disable_api_termination = False
   
    # create instance(s)
    print('Creating instance...')
    instances = ec2.create_instances(
        ImageId=image_id,
        MinCount=1,
        MaxCount=1,
        KeyName=ssh_key_name,
        UserData=user_data,
        InstanceType=instance_type,
        BlockDeviceMappings=block_device_mappings,
        DisableApiTermination=disable_api_termination,
        NetworkInterfaces=network_interfaces,
        EbsOptimized=ebs_optimized
    )

    # add tags
    print('Tagging...')
    for instance in instances:
        instance.create_tags(
            Tags=[
                {
                    'Key': 'Name',
                    'Value': 'Bogdan_boto_test'
                }
            ]
        )

    # wait for instance(s) to start
    instance_ids = []
    for instance in instances:
        instance_ids.append(instance.id)

    print('Waiting for running state')
    waiter = ec2.meta.client.get_waiter('instance_running')
    waiter.wait(InstanceIds=instance_ids)
    for instance in instances:
        print(instance.private_ip_address, instance.public_ip_address)
    print('Waiting for status ok')
    waiter = ec2.meta.client.get_waiter('instance_status_ok')
    waiter.wait(InstanceIds=instance_ids)
    print('Waiting for console output')
    waiter = ec2.meta.client.get_waiter('console_output_available')
    waiter.wait(InstanceId=instance_ids[0])

def get_amazon_linux_ami():
    # A dummy function for now, when developped it should return one and only
    # one id of an Amazon Linux AMI to be used. Arguments can be passed on to
    # to identify the exact image. 'latest' should return the newest version
    # of Amazon Linux, HVM, EBS-Backed, 64-bit (the most used image),
    # depending on region
    return 'ami-bff32ccc'


def get_root_device_name(image_id):
    # will return the device name for a particular image (ex. '/dev/sda1')
    return '/dev/xvda'


def get_user_data(file_name=False):
    # Returns user data to be passed to cloud-init on instance launch.
    # i.e. add ansible user, add proper ssh key. The commands to run could be
    # defined here, or loaded from a text file. Maybe use a parameter for that
    user_data = ''
    if file_name:
        with open(file_name, 'r') as f:
            user_data = f.read()
    return user_data


if __name__ == "__main__":
    # execute only if run as a script
    main()