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boxpy/box.py
gryf 1e8bd7a37d Do not relay on vboxmanage output.
There is a function which retrieve information about VM by looking on
the 'vboxmanage vminfo' command. The output wasn't consistent, yet it
was fixed recently so that amount of memory was all wrong.

Currently the only thing which is searched for is the VM configuration
path, and all the rest is taken out from the XML VM definition.
2021-05-06 20:53:36 +02:00

822 lines
27 KiB
Python
Executable File

#!/usr/bin/env python
import argparse
import collections.abc
import os
import shutil
import string
import subprocess
import sys
import tempfile
import time
import uuid
import xml.dom.minidom
import yaml
CACHE_DIR = os.environ.get('XDG_CACHE_HOME', os.path.expanduser('~/.cache'))
CLOUD_IMAGE = "ci.iso"
META_DATA_TPL = string.Template('''\
instance-id: $instance_id
local-hostname: $vmhostname
''')
UBUNTU_VERSION = '20.04'
USER_DATA = '''\
#cloud-config
users:
- default
- name: ubuntu
ssh_authorized_keys:
- $ssh_key
chpasswd: { expire: False }
gecos: ubuntu
sudo: ALL=(ALL) NOPASSWD:ALL
groups: users, admin
power_state:
mode: poweroff
timeout: 10
condition: True
boxpy_data:
cpus: 1
disk_size: 10240
key: ~/.ssh/id_rsa
memory: 2048
port: 2222
version: 20.04
'''
COMPLETIONS = {'bash': '''\
_boxpy() {
local cur prev words cword _GNUSED
_GNUSED=${GNUSED:-sed}
# Complete registered VM names.
# Issues are the same as in above function.
_vms_comp() {
local command=$1
local exclude_running=false
local vms
local running_vms
local item
compopt -o filenames
if [[ $# == 2 ]]
then
exclude_running=true
running_vms=$(VBoxManage list runningvms | \
awk -F ' {' '{ print $1 }' | \
tr '\n' '|' | \
$_GNUSED 's/|$//' | \
$_GNUSED 's/"//g')
IFS='|' read -ra running_vms <<< "$running_vms"
fi
vms=$(VBoxManage list $command | \
awk -F ' {' '{ print $1 }' | \
tr '\n' '|' | \
$_GNUSED 's/|$//' | \
$_GNUSED 's/"//g')
IFS='|' read -ra vms <<< "$vms"
for item in "${vms[@]}"
do
if $exclude_running
then
_is_in_array "$item" "${running_vms[@]}"
[[ $? == 0 ]] && continue
fi
[[ ${item^^} == ${cur^^}* ]] && COMPREPLY+=("$item")
done
}
_get_excluded_items() {
local i
result=""
for i in $@; do
[[ " ${COMP_WORDS[@]} " == *" $i "* ]] && continue
result="$result $i"
done
}
_ssh_identityfile() {
[[ -z $cur && -d ~/.ssh ]] && cur=~/.ssh/id
_filedir
if ((${#COMPREPLY[@]} > 0)); then
COMPREPLY=($(compgen -W '${COMPREPLY[@]}' \
-X "${1:+!}*.pub" -- "$cur"))
fi
}
COMP_WORDBREAKS=${COMP_WORDBREAKS//|/} # remove pipe from comp word breaks
COMPREPLY=()
cur="${COMP_WORDS[COMP_CWORD]}"
prev="${COMP_WORDS[COMP_CWORD-1]}"
if [[ COMP_CWORD -ge 2 ]]; then
cmd="${COMP_WORDS[1]}"
if [[ $cmd == "-q" ]]; then
cmd="${COMP_WORDS[2]}"
fi
fi
opts="create destroy rebuild list completion"
if [[ ${cur} == "-q" || ${cur} == "-v" || ${COMP_CWORD} -eq 1 ]] ; then
COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
return 0
fi
case "${cmd}" in
completion)
if [[ ${prev} == ${cmd} ]]; then
COMPREPLY=( $(compgen -W "bash" -- ${cur}) )
fi
;;
create|rebuild)
items=(--cpus --disk-size --key --memory --hostname
--port --cloud-config --version)
if [[ ${prev} == ${cmd} ]]; then
if [[ ${cmd} = "rebuild" ]]; then
_vms_comp vms
else
COMPREPLY=( $(compgen -W "${items[*]}" -- ${cur}) )
fi
else
_get_excluded_items "${items[@]}"
COMPREPLY=( $(compgen -W "$result" -- ${cur}) )
case "${prev}" in
--cloud-config)
COMPREPLY=( $(compgen -f -- ${cur}) )
;;
--key)
_ssh_identityfile
;;
esac
fi
;;
destroy)
if [[ ${prev} == ${cmd} ]]; then
_vms_comp vms
fi
;;
list)
items=(--long --running)
_get_excluded_items "${items[@]}"
COMPREPLY=( $(compgen -W "$result" -- ${cur}) )
;;
esac
}
complete -o default -F _boxpy boxpy
'''}
def convert_to_mega(size):
"""
Vritualbox uses MB as a common denominator for amount of memory or disk
size. This function will return string of MB from string which have human
readable suffix, like M or G. Case insensitive.
"""
if size.isnumeric():
return str(size)
if size.lower().endswith('m') and size[:-1].isnumeric():
return str(size[:-1])
if size.lower().endswith('g') and size[:-1].isnumeric():
return str(int(size[:-1]) * 1024)
if size.lower().endswith('mb') and size[:-2].isnumeric():
return str(size[:-2])
if size.lower().endswith('gb') and size[:-2].isnumeric():
return str(int(size[:-2]) * 1024)
class BoxError(Exception):
pass
class BoxNotFound(BoxError):
pass
class BoxVBoxFailure(BoxError):
pass
class BoxConvertionError(BoxError):
pass
class BoxSysCommandError(BoxError):
pass
class Config:
ATTRS = ('cpus', 'cloud_config', 'disk_size', 'hostname', 'key',
'memory', 'name', 'port', 'version')
def __init__(self, args, vbox=None):
self.advanced = None
self.cpus = None
self.disk_size = None
self.hostname = None
self.key = None
self.memory = None
self.name = args.name # this one is not stored anywhere
self.port = None # at least is not even tried to be retrieved
self.version = None
self._conf = {}
# set defaults stored in hard coded yaml
self._set_defaults()
# look at VM metadata, and gather known attributes, and update it
# accordingly
vm_info = vbox.get_vm_info() if vbox else {}
for attr in self.ATTRS:
if not vm_info.get(attr):
continue
setattr(self, attr, vm_info[attr])
# next, grab the cloud config file
self.user_data = args.cloud_config or vm_info.get('user_data')
# combine it with the defaults, set attributes by boxpy_data
# definition, if found
self._combine_cc(vbox)
# than, override all of the attributes with provided arguments from
# the command line
vm_info = vbox.get_vm_info() if vbox else {}
for attr in self.ATTRS:
val = getattr(args, attr, None) or vm_info.get(attr)
if not val:
continue
setattr(self, attr, str(val))
# finally, figure out host name
self.hostname = self.hostname or self._normalize_name()
def get_cloud_config_tpl(self):
conf = "#cloud-config\n" + yaml.safe_dump(self._conf)
return string.Template(conf)
def _set_defaults(self):
conf = yaml.safe_load(USER_DATA)
# update attributes with default values
for key, val in conf['boxpy_data'].items():
setattr(self, key, str(val))
def _normalize_name(self):
name = self.name.replace(' ', '-')
name = name.encode('ascii', errors='ignore')
name = name.decode('utf-8')
return ''.join(x for x in name if x.isalnum() or x == '-')
def _combine_cc(self, vbox):
conf = yaml.safe_load(USER_DATA)
# read user custom cloud config (if present) and update config dict
if self.user_data and os.path.exists(self.user_data):
with open(self.user_data) as fobj:
custom_conf = yaml.safe_load(fobj)
conf = self._update(conf, custom_conf)
# update the attributes with data from read user cloud config
for key, val in conf.get('boxpy_data', {}).items():
if not val:
continue
setattr(self, key, str(val))
# remove boxpy_data since it will be not needed on the guest side
if conf.get('boxpy_data'):
if conf['boxpy_data'].get('advanced'):
self.advanced = conf['boxpy_data']['advanced']
del conf['boxpy_data']
self._conf = conf
def _update(self, source, update):
for key, val in update.items():
if isinstance(val, collections.abc.Mapping):
source[key] = self._update(source.get(key, {}), val)
else:
source[key] = val
return source
class VBoxManage:
"""
Class for dealing with vboxmanage commands
"""
def __init__(self, name_or_uuid=None):
self.name_or_uuid = name_or_uuid
self.vm_info = {}
def get_vm_base_path(self):
path = self._get_vm_config()
if not path:
return
return os.path.dirname(path)
def get_disk_path(self):
path = self._get_vm_config()
if not path:
return
dom = xml.dom.minidom.parse(path)
if len(dom.getElementsByTagName('HardDisk')) != 1:
# don't know what to do with multiple discs
raise BoxError('Cannot deal with multiple attached disks, perhaps '
'you need to do this manually')
disk = dom.getElementsByTagName('HardDisk')[0]
location = disk.getAttribute('location')
if location.startswith('/'):
disk_path = location
else:
disk_path = os.path.join(self.get_vm_base_path(), location)
return disk_path
def get_media_size(self, media_path):
try:
out = subprocess.check_output(['vboxmanage', 'showmediuminfo',
media_path],
encoding=sys.getdefaultencoding(),
stderr=subprocess.DEVNULL)
except subprocess.CalledProcessError:
return None
for line in out.split('\n'):
if line.startswith('Capacity:'):
line = line.split('Capacity:')[1].strip()
if line.isnumeric():
return line
else:
return line.split(' ')[0].strip()
def get_vm_info(self):
try:
out = subprocess.check_output(['vboxmanage', 'showvminfo',
self.name_or_uuid],
encoding=sys.getdefaultencoding(),
stderr=subprocess.DEVNULL)
except subprocess.CalledProcessError:
return None
self.vm_info = {}
for line in out.split('\n'):
if line.startswith('Config file:'):
self.vm_info['config_file'] = line.split('Config '
'file:')[1].strip()
break
dom = xml.dom.minidom.parse(self.vm_info['config_file'])
gebtn = dom.getElementsByTagName
self.vm_info['cpus'] = gebtn('CPU')[0].getAttribute('count')
self.vm_info['uuid'] = gebtn('Machine')[0].getAttribute('uuid')[1:-1]
self.vm_info['memory'] = gebtn('Memory')[0].getAttribute('RAMSize')
for extradata in gebtn('ExtraDataItem'):
key = extradata.getAttribute('name')
val = extradata.getAttribute('value')
self.vm_info[key] = val
if len(gebtn('Forwarding')):
fw = gebtn('Forwarding')[0].getAttribute('hostport')
self.vm_info['port'] = fw
return self.vm_info
def poweroff(self, silent=False):
cmd = ['vboxmanage', 'controlvm', self.name_or_uuid, 'poweroff']
if silent:
subprocess.call(cmd, stderr=subprocess.DEVNULL)
else:
subprocess.call(cmd)
def vmlist(self, only_running=False, long_list=False):
subcommand = 'runningvms' if only_running else 'vms'
long_list = '-l' if long_list else '-s'
subprocess.call(['vboxmanage', 'list', subcommand, long_list])
def get_running_vms(self):
return subprocess.getoutput('vboxmanage list runningvms')
def destroy(self):
self.poweroff(silent=True)
if subprocess.call(['vboxmanage', 'unregistervm', self.name_or_uuid,
'--delete']) != 0:
raise BoxVBoxFailure(f'Removing VM {self.name_or_uuid} failed')
def create(self, cpus, memory, port):
self.uuid = None
memory = convert_to_mega(memory)
try:
out = subprocess.check_output(['vboxmanage', 'createvm', '--name',
self.name_or_uuid, '--register'],
encoding=sys.getdefaultencoding())
except subprocess.CalledProcessError:
return None
for line in out.split('\n'):
print(line)
if line.startswith('UUID:'):
self.uuid = line.split('UUID:')[1].strip()
if not self.uuid:
raise BoxVBoxFailure(f'Cannot create VM "{self.name_or_uuid}".')
if subprocess.call(['vboxmanage', 'modifyvm', self.name_or_uuid,
'--memory', str(memory),
'--cpus', str(cpus),
'--boot1', 'disk',
'--acpi', 'on',
'--audio', 'none',
'--nic1', 'nat',
'--natpf1', f'guestssh,tcp,,{port},,22']) != 0:
raise BoxVBoxFailure(f'Cannot modify VM "{self.name_or_uuid}".')
return self.uuid
def convertfromraw(self, src, dst):
if subprocess.call(["vboxmanage", "convertfromraw", src, dst]) != 0:
os.unlink(src)
raise BoxVBoxFailure('Cannot convert image to VDI.')
os.unlink(src)
def closemedium(self, type_, mediumpath):
if subprocess.call(['vboxmanage', 'closemedium', type_,
mediumpath]) != 0:
raise BoxVBoxFailure(f'Failed close medium {mediumpath}.')
def create_controller(self, name, type_):
if subprocess.call(['vboxmanage', 'storagectl', self.name_or_uuid,
'--name', name, '--add', type_]) != 0:
raise BoxVBoxFailure(f'Adding controller {type_} has failed.')
def move_and_resize_image(self, src, dst, size):
fullpath = os.path.join(self.get_vm_base_path(), dst)
size = convert_to_mega(size)
if subprocess.call(['vboxmanage', 'modifymedium', 'disk', src,
'--resize', str(size), '--move', fullpath]) != 0:
raise BoxVBoxFailure(f'Resizing and moving image {dst} has '
f'failed')
return fullpath
def storageattach(self, controller_name, port, type_, image):
if subprocess.call(['vboxmanage', 'storageattach', self.name_or_uuid,
'--storagectl', controller_name,
'--port', str(port),
'--device', '0',
'--type', type_,
'--medium', image]) != 0:
raise BoxVBoxFailure(f'Attaching {image} to VM has failed.')
def poweron(self):
if subprocess.call(['vboxmanage', 'startvm', self.name_or_uuid,
'--type', 'headless']) != 0:
raise BoxVBoxFailure(f'Failed to start: {self.name_or_uuid}.')
def setextradata(self, key, val):
if subprocess.call(['vboxmanage', 'setextradata', self.name_or_uuid,
key, val]) != 0:
raise BoxVBoxFailure(f'Failed to start: {self.name_or_uuid}.')
def add_nic(self, nic, kind):
if subprocess.call(['vboxmanage', 'modifyvm', self.name_or_uuid,
f'--{nic}', kind]) != 0:
raise BoxVBoxFailure(f'Cannot modify VM "{self.name_or_uuid}".')
def _get_vm_config(self):
if self.vm_info.get('config_file'):
return self.vm_info['config_file']
self.get_vm_info()
if self.vm_info.get('config_file'):
return self.vm_info['config_file']
class Image:
def __init__(self, vbox, version, arch='amd64'):
self.version = version
self.arch = arch
self.vbox = vbox
self._tmp = tempfile.mkdtemp()
self._img = f"ubuntu-{self.version}-server-cloudimg-{self.arch}.img"
def convert_to_vdi(self, disk_img, size):
self._download_image()
self._convert_to_raw()
raw_path = os.path.join(self._tmp, self._img + ".raw")
vdi_path = os.path.join(self._tmp, disk_img)
self.vbox.convertfromraw(raw_path, vdi_path)
return self.vbox.move_and_resize_image(vdi_path, disk_img, size)
def _checksum(self):
"""
Get and check checkusm for downloaded image. Return True if the
checksum is correct, False otherwise.
"""
if not os.path.exists(os.path.join(CACHE_DIR, self._img)):
return False
expected_sum = None
fname = 'SHA256SUMS'
url = "https://cloud-images.ubuntu.com/releases/"
url += f"{self.version}/release/{fname}"
# TODO: make the verbosity switch be dependent from verbosity of the
# script.
subprocess.call(['wget', url, '-q', '-O',
os.path.join(self._tmp, fname)])
with open(os.path.join(self._tmp, fname)) as fobj:
for line in fobj.readlines():
if self._img in line:
expected_sum = line.split(' ')[0]
break
if not expected_sum:
raise BoxError('Cannot find provided cloud image')
if os.path.exists(os.path.join(CACHE_DIR, self._img)):
cmd = 'sha256sum ' + os.path.join(CACHE_DIR, self._img)
calulated_sum = subprocess.getoutput(cmd).split(' ')[0]
return calulated_sum == expected_sum
return False
def cleanup(self):
subprocess.call(['rm', '-fr', self._tmp])
def _convert_to_raw(self):
img_path = os.path.join(CACHE_DIR, self._img)
raw_path = os.path.join(self._tmp, self._img + ".raw")
if subprocess.call(['qemu-img', 'convert', '-O', 'raw',
img_path, raw_path]) != 0:
raise BoxConvertionError(f'Cannot convert image {self._img} to '
'RAW.')
def _download_image(self):
if self._checksum():
print(f'Image already downloaded: {self._img}')
return
url = "https://cloud-images.ubuntu.com/releases/"
url += f"{self.version}/release/"
url += self._img
print(f'Downloading image {self._img}')
subprocess.call(['wget', '-q', url, '-O', os.path.join(CACHE_DIR,
self._img)])
if not self._checksum():
# TODO: make some retry mechanism?
raise BoxSysCommandError('Checksum for downloaded image differ '
'from expected.')
else:
print(f'Downloaded image {self._img}')
class IsoImage:
def __init__(self, conf):
self._tmp = tempfile.mkdtemp()
self.hostname = conf.hostname
self.ssh_key_path = conf.key
if not self.ssh_key_path.endswith('.pub'):
self.ssh_key_path += '.pub'
if not os.path.exists(self.ssh_key_path):
self.ssh_key_path = os.path.join(os.path
.expanduser(self.ssh_key_path))
if not os.path.exists(self.ssh_key_path):
self.ssh_key_path = os.path.join(os.path.expanduser("~/.ssh"),
self.ssh_key_path)
if not os.path.exists(self.ssh_key_path):
raise BoxNotFound(f'Cannot find ssh public key: {conf.key}')
self.ud_tpl = conf.get_cloud_config_tpl()
def get_generated_image(self):
self._create_cloud_image()
return os.path.join(self._tmp, CLOUD_IMAGE)
def cleanup(self):
subprocess.call(['rm', '-fr', self._tmp])
def _create_cloud_image(self):
# meta-data
with open(os.path.join(self._tmp, 'meta-data'), 'w') as fobj:
fobj.write(META_DATA_TPL
.substitute({'instance_id': str(uuid.uuid4()),
'vmhostname': self.hostname}))
# user-data
with open(self.ssh_key_path) as fobj:
ssh_pub_key = fobj.read().strip()
with open(os.path.join(self._tmp, 'user-data'), 'w') as fobj:
fobj.write(self.ud_tpl.substitute({'ssh_key': ssh_pub_key}))
mkiso = 'mkisofs' if shutil.which('mkisofs') else 'genisoimage'
# create ISO image
if subprocess.call([mkiso, '-J', '-R', '-V', 'cidata', '-o',
os.path.join(self._tmp, CLOUD_IMAGE),
os.path.join(self._tmp, 'user-data'),
os.path.join(self._tmp, 'meta-data')]) != 0:
raise BoxSysCommandError('Cannot create ISO image for config '
'drive')
def vmcreate(args, conf=None):
if not conf:
conf = Config(args)
vbox = VBoxManage(conf.name)
if not vbox.create(conf.cpus, conf.memory, conf.port):
return 10
vbox.create_controller('IDE', 'ide')
vbox.create_controller('SATA', 'sata')
vbox.setextradata('key', conf.key)
vbox.setextradata('hostname', conf.hostname)
vbox.setextradata('version', conf.version)
if conf.user_data:
vbox.setextradata('user_data', conf.user_data)
image = Image(vbox, conf.version)
path_to_disk = image.convert_to_vdi(conf.name + '.vdi', conf.disk_size)
iso = IsoImage(conf)
path_to_iso = iso.get_generated_image()
vbox.storageattach('SATA', 0, 'hdd', path_to_disk)
vbox.storageattach('IDE', 1, 'dvddrive', path_to_iso)
# advanced options, currnetly pretty hardcoded
if conf.advanced:
for key, val in conf.advanced.items():
if key.startswith('nic'):
vbox.add_nic(key, val)
# start the VM and wait for cloud-init to finish
vbox.poweron()
# give VBox some time to actually change the state of the VM before query
time.sleep(3)
def _cleanup(vbox, iso, image, path_to_iso):
time.sleep(1) # wait a bit, for VM shutdown to complete
vbox.storageattach('IDE', 1, 'dvddrive', 'none')
vbox.closemedium('dvd', path_to_iso)
iso.cleanup()
image.cleanup()
# than, let's try to see if boostraping process has finished
print('Waiting for cloud init to finish ', end='')
try:
while True:
if vbox.vm_info['uuid'] in vbox.get_running_vms():
print('.', end='')
sys.stdout.flush()
time.sleep(3)
else:
print(' done.')
break
except KeyboardInterrupt:
print('\nIterrupted, cleaning up.')
vbox.poweroff(silent=True)
_cleanup(vbox, iso, image, path_to_iso)
vbox.destroy()
return 1
# dettach ISO image
_cleanup(vbox, iso, image, path_to_iso)
vbox.poweron()
print('You can access your VM by issuing:')
print(f'ssh -p {conf.port} -i {iso.ssh_key_path[:-4]} ubuntu@localhost')
return 0
def vmdestroy(args):
VBoxManage(args.name).destroy()
return 0
def vmlist(args):
VBoxManage().vmlist(args.running, args.long)
return 0
def vmrebuild(args):
vbox = VBoxManage(args.name)
conf = Config(args, vbox)
vbox.poweroff(silent=True)
disk_path = vbox.get_disk_path()
if not disk_path:
# no disks, return
return 1
if not conf.disk_size:
conf.disk_size = vbox.get_media_size(disk_path)
vmdestroy(args)
vmcreate(args, conf)
return 0
def shell_completion(args):
sys.stdout.write(COMPLETIONS[args.shell])
return 0
def main():
parser = argparse.ArgumentParser(description="Automate deployment and "
"maintenance of Ubuntu VMs using "
"VirtualBox and Ubuntu cloud images")
subparsers = parser.add_subparsers(help='supported commands')
create = subparsers.add_parser('create', help='create and configure VM, '
'create corresponding assets, config '
'drive and run')
create.set_defaults(func=vmcreate)
create.add_argument('name', help='name of the VM')
create.add_argument('-c', '--cpus', type=int, help="amount of CPUs to be "
"configured. Default 1.")
create.add_argument('-d', '--disk-size', help="disk size to be expanded "
"to. By default to 10GB")
create.add_argument('-k', '--key', help="SSH key to be add to the config "
"drive. Default ~/.ssh/id_rsa")
create.add_argument('-m', '--memory', help="amount of memory in "
"Megabytes, default 2GB")
create.add_argument('-n', '--hostname',
help="VM hostname. Default same as vm name")
create.add_argument('-p', '--port', help="set ssh port for VM, default "
"2222")
create.add_argument('-u', '--cloud-config',
help="Alternative user-data template filepath")
create.add_argument('-v', '--version', help=f"Ubuntu server version. "
f"Default {UBUNTU_VERSION}")
destroy = subparsers.add_parser('destroy', help='destroy VM')
destroy.add_argument('name', help='name or UUID of the VM')
destroy.set_defaults(func=vmdestroy)
list_vms = subparsers.add_parser('list', help='list VMs')
list_vms.add_argument('-l', '--long', action='store_true',
help='show detailed information '
'about VMs')
list_vms.add_argument('-r', '--running', action='store_true',
help='show only running VMs')
list_vms.set_defaults(func=vmlist)
rebuild = subparsers.add_parser('rebuild', help='Rebuild VM, all options '
'besides vm name are optional, and their '
'values will be taken from vm definition.')
rebuild.add_argument('name', help='name or UUID of the VM')
rebuild.add_argument('-c', '--cpus', type=int,
help='amount of CPUs to be configured')
rebuild.add_argument('-d', '--disk-size',
help='disk size to be expanded to')
rebuild.add_argument('-k', '--key',
help='SSH key to be add to the config drive')
rebuild.add_argument('-m', '--memory', help='amount of memory in '
'Megabytes')
rebuild.add_argument('-n', '--hostname', help="set VM hostname")
rebuild.add_argument('-p', '--port', help="set ssh port for VM")
rebuild.add_argument('-u', '--cloud-config',
help="Alternative user-data template filepath")
rebuild.add_argument('-v', '--version', help='Ubuntu server version')
rebuild.set_defaults(func=vmrebuild)
completion = subparsers.add_parser('completion', help='generate shell '
'completion')
completion.add_argument('shell', choices=['bash'],
help="pick shell to generate completions for")
completion.set_defaults(func=shell_completion)
args = parser.parse_args()
if hasattr(args, 'func'):
return args.func(args)
parser.print_help()
parser.exit()
if __name__ == '__main__':
sys.exit(main())