scw

#!/usr/bin/env python3

import subprocess
import sys

SCW_TYPE = 'DEV1-S'
SCW_ZONE = 'nl-ams-1'
SCW_IMAGE = 'centos_8'
SCW_PROJECT_ID = '<projectid>'
LOG_CMD = False


def exec_cmd(c):
    if LOG_CMD: print(c)
    subprocess.call(c.split())


def do_create():
    for i in range(1, 4):
        exec_cmd(
            f'scw instance server create type={SCW_TYPE} zone={SCW_ZONE} image={SCW_IMAGE}'
            f' name=node{i:02} ip=new project-id={SCW_PROJECT_ID}'
        )


def do_list():
    exec_cmd(f'scw instance server list zone={SCW_ZONE}')


def do_delete():
    def list_server_ids():
        cmd = f"scw instance server list zone={SCW_ZONE} | tail -n +2 |  awk '{{print $1}}'"
        out = subprocess.check_output(cmd, shell=True).splitlines()
        return [b.decode('UTF-8') for b in out]

    ids = list_server_ids()
    if not ids:
        print(f'no servers found in zone: {SCW_ZONE}')
        return

    for server_id in ids:
        exec_cmd(f'scw instance server delete {server_id} zone={SCW_ZONE} force-shutdown=true')


def main():
    command = sys.argv[1] if len(sys.argv) > 1 else None

    if command == 'create':
        do_create()
    elif command == 'delete':
        do_delete()
    elif command == 'list':
        do_list()
    else:
        print('invalid command')


if __name__ == '__main__':
    main()

We could refactor the main function to something like that:

def main():
    command = sys.argv[1] if len(sys.argv) > 1 else None
    commands = {
        "create": do_create,
        "delete": do_delete,
        "list": do_list
    }
    try:
        commands[command]()
    except KeyError:
        print('invalid command')
     

@ahm3dmelh4dy
Wow, I like it... Thanks for the update 👍

Can we avoid try catch by using get or using an if gaurd?

Yeah, I think we could do something like that:

def main():
    command = sys.argv[1] if len(sys.argv) > 1 else None
    commands = {
        "create": do_create,
        "delete": do_delete,
        "list": do_list
    }

    # set a default value to return if the key is not found.
    error_msg = "invalid command"
    result = commands.get(command, error_msg)
    
    if result == error_msg:
        print(result)
    else:
        result()

@ahm3dmelh4dy ❤️