Rackspace CloudServers tools for Fabric

rscloud.py

"""Rackspace CloudServers tools for Fabric"""
import os

from cloudservers import CloudServers
from fabric.api import task, prompt
from fabric.contrib.console import confirm


RS_USER = os.environ.get('CLOUD_SERVERS_USERNAME')
RS_API_KEY = os.environ.get('CLOUD_SERVERS_API_KEY')
cloudservers = None


def _ensure_cs():
    """Ensures a Rackspace CloudServers instance is attempted."""
    global cloudservers
    if cloudservers is None:
        print("Authenticating with Rackspace...")
        cloudservers = CloudServers(RS_USER, RS_API_KEY)
    return cloudservers


def _get_as_list_and_choices(iter, ident):
    """Returns a list of items and choice text for the given iterable"""
    choices = ['%s. %s' % (idx, name) for idx, name in enumerate(iter)]
    choice_txt = 'Available %s list:\n' % ident
    choice_txt += '\n'.join(choices)
    choice_txt += '\nPlease select a(n) %s (by number):' % ident
    return iter, choice_txt


def _name_is_unique(name):
    """Fabric validation method to determine if the given server name is
    unique.
    """
    cs = _ensure_cs()
    print('Validating name "%s" with Rackspace...' % name)
    servers = cs.servers.list()
    names = [svr.name.lower() for svr in servers]
    if name.lower() in names:
        exc_txt = 'Server already exists with name "%s". Existing Servers:\n' % name
        exc_txt += "\n".join(names)
        raise Exception(exc_txt)
    return name


@task
def create_server():
    cs = _ensure_cs()
    
    print("Retreving images...")
    images, img_choices = _get_as_list_and_choices(cs.images.list(), 'image')
    img_idx = int(prompt(img_choices, validate=r'\d+'))
    image = images[img_idx]
    
    print("Retreving flavors...")
    flavors, flv_choices = _get_as_list_and_choices(cs.flavors.list(), 'flavor')
    flv_idx = int(prompt(flv_choices, validate=r'\d+'))
    flavor = flavors[flv_idx]
    
    name = prompt('Server name:', validate=_name_is_unique)
    
    bld_txt = "Create server \"%s\" (%s, %s)?" % (name, image, flavor)
    if confirm(bld_txt):
        cs.servers.create(name, image, flavor)