uncloud-mravi/common/storage_handlers.py
meow cc0ca68498 * Refactoring
* Fix issue that causes a new image store to be created at every start of ucloud-api.
* VM Migration API call now takes hostname instead of host key.
* StorageHandler Classes are introduced. They transparently handles things related to importing of image, make vm out of image, resize vm image, delete vm image etc.
* Loggers added to __init__.py of every ucloud component's subpackage.
* Non-Trivial Timeout Events are no longer logged.
* Fix issue that prevents removal of stopped VMs (i.e VMs that are successfully migrated).
* Improved unit handling added. e.g MB, Mb, mB, mb are all Mega Bytes.
* VM migration is now possible on IPv6 host.
* Destination VM (receiving side of migration of a vm) now correctly expects incoming data on free ephemeral port.
* Traceback is no longer output to screen, instead it goes to log file.
* All sanity checks are put into a single file. These checks are run by ucloud.py before running any of ucloud component.
2019-11-25 11:52:36 +05:00

158 lines
4.9 KiB
Python

import shutil
import subprocess as sp
import os
import stat
from abc import ABC
from host import logger
from os.path import join as join_path
class ImageStorageHandler(ABC):
def __init__(self, image_base, vm_base):
self.image_base = image_base
self.vm_base = vm_base
def import_image(self, image_src, image_dest, protect=False):
"""Put an image at the destination
:param src: An Image file
:param dest: A path where :param src: is to be put.
:param protect: If protect is true then the dest is protect (readonly etc)
The obj must exist on filesystem.
"""
raise NotImplementedError()
def make_vm_image(self, image_path, path):
"""Copy image from src to dest
:param src: A path
:param dest: A path
src and destination must be on same storage system i.e both on file system or both on CEPH etc.
"""
raise NotImplementedError()
def resize_vm_image(self, path, size):
"""Resize image located at :param path:
:param path: The file which is to be resized
:param size: Size must be in Megabytes
"""
raise NotImplementedError()
def delete_vm_image(self, path):
raise NotImplementedError()
def execute_command(self, command, report=True):
command = list(map(str, command))
try:
output = sp.check_output(command, stderr=sp.PIPE)
except Exception as e:
if report:
print(e)
logger.exception(e)
return False
return True
def vm_path_string(self, path):
raise NotImplementedError()
def qemu_path_string(self, path):
raise NotImplementedError()
def is_vm_image_exists(self, path):
raise NotImplementedError()
class FileSystemBasedImageStorageHandler(ImageStorageHandler):
def import_image(self, src, dest, protect=False):
dest = join_path(self.image_base, dest)
try:
shutil.copy(src, dest)
if protect:
os.chmod(dest, stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH)
except Exception as e:
logger.exception(e)
return False
return True
def make_vm_image(self, src, dest):
src = join_path(self.image_base, src)
dest = join_path(self.vm_base, dest)
try:
shutil.copy(src, dest)
except Exception as e:
logger.exception(e)
return False
return True
def resize_vm_image(self, path, size):
path = join_path(self.vm_base, path)
command = ["qemu-img", "resize", "-f", "raw", path, "{}M".format(size)]
if self.execute_command(command):
return True
else:
self.delete_vm_image(path)
return False
def delete_vm_image(self, path):
path = join_path(self.vm_base, path)
try:
os.remove(path)
except Exception as e:
logger.exception(e)
return False
return True
def vm_path_string(self, path):
return join_path(self.vm_base, path)
def qemu_path_string(self, path):
return self.vm_path_string(path)
def is_vm_image_exists(self, path):
path = join_path(self.vm_base, path)
command = ["ls", path]
return self.execute_command(command, report=False)
class CEPHBasedImageStorageHandler(ImageStorageHandler):
def import_image(self, src, dest, protect=False):
dest = join_path(self.image_base, dest)
command = ["rbd", "import", src, dest]
if protect:
snap_create_command = ["rbd", "snap", "create", "{}@protected".format(dest)]
snap_protect_command = ["rbd", "snap", "protect", "{}@protected".format(dest)]
return self.execute_command(command) and self.execute_command(snap_create_command) and\
self.execute_command(snap_protect_command)
return self.execute_command(command)
def make_vm_image(self, src, dest):
src = join_path(self.image_base, src)
dest = join_path(self.vm_base, dest)
command = ["rbd", "clone", "{}@protected".format(src), dest]
return self.execute_command(command)
def resize_vm_image(self, path, size):
path = join_path(self.vm_base, path)
command = ["rbd", "resize", path, "--size", size]
return self.execute_command(command)
def delete_vm_image(self, path):
path = join_path(self.vm_base, path)
command = ["rbd", "rm", path]
return self.execute_command(command)
def vm_path_string(self, path):
return join_path(self.vm_base, path)
def qemu_path_string(self, path):
return "rbd:{}".format(self.vm_path_string(path))
def is_vm_image_exists(self, path):
path = join_path(self.vm_base, path)
command = ["rbd", "info", path]
return self.execute_command(command, report=False)