core-extra/daemon/core/nodes/lxd.py

301 lines
9.2 KiB
Python

import json
import logging
import os
import time
from core import utils, CoreCommandError
from core.emulator.enumerations import NodeTypes
from core.nodes.base import CoreNode
class LxdClient(object):
def __init__(self, name, image):
self.name = name
self.image = image
self.pid = None
self._addr = {}
def create_container(self):
utils.check_cmd("lxc launch {image} {name}".format(
name=self.name,
image=self.image
))
data = self.get_info()
self.pid = data["state"]["pid"]
return self.pid
def get_info(self):
args = "lxc list {name} --format json".format(name=self.name)
status, output = utils.cmd_output(args)
if status:
raise CoreCommandError(status, args, output)
data = json.loads(output)
if not data:
raise CoreCommandError(status, args, "LXC({name}) not present".format(name=self.name))
return data[0]
def is_alive(self):
try:
data = self.get_info()
return data["state"]["status"] == "Running"
except CoreCommandError:
return False
def stop_container(self):
utils.check_cmd("lxc delete --force {name}".format(
name=self.name
))
def _cmd_args(self, cmd):
return "lxc exec -nT {name} -- {cmd}".format(
name=self.name,
cmd=cmd
)
def cmd_output(self, cmd):
if isinstance(cmd, list):
cmd = " ".join(cmd)
args = self._cmd_args(cmd)
logging.info("lxc cmd output: %s", args)
return utils.cmd_output(args)
def cmd(self, cmd, wait=True):
if isinstance(cmd, list):
cmd = " ".join(cmd)
args = self._cmd_args(cmd)
logging.info("lxc cmd: %s", args)
return utils.cmd(args, wait)
def _ns_args(self, cmd):
return "nsenter -t {pid} -m -u -i -p -n {cmd}".format(
pid=self.pid,
cmd=cmd
)
def ns_cmd_output(self, cmd):
if isinstance(cmd, list):
cmd = " ".join(cmd)
args = self._ns_args(cmd)
logging.info("ns cmd: %s", args)
return utils.cmd_output(args)
def ns_cmd(self, cmd, wait=True):
if isinstance(cmd, list):
cmd = " ".join(cmd)
args = self._ns_args(cmd)
logging.info("ns cmd: %s", args)
return utils.cmd(args, wait)
def copy_file(self, source, destination):
if destination[0] != "/":
destination = os.path.join("/root/", destination)
args = "lxc file push {source} {name}/{destination}".format(
source=source,
name=self.name,
destination=destination
)
status, output = utils.cmd_output(args)
if status:
raise CoreCommandError(status, args, output)
def getaddr(self, ifname, rescan=False):
"""
Get address for interface on node.
:param str ifname: interface name to get address for
:param bool rescan: rescan flag
:return: interface information
:rtype: dict
"""
if ifname in self._addr and not rescan:
return self._addr[ifname]
interface = {"ether": [], "inet": [], "inet6": [], "inet6link": []}
args = ["ip", "addr", "show", "dev", ifname]
status, output = self.ns_cmd_output(args)
for line in output:
line = line.strip().split()
if line[0] == "link/ether":
interface["ether"].append(line[1])
elif line[0] == "inet":
interface["inet"].append(line[1])
elif line[0] == "inet6":
if line[3] == "global":
interface["inet6"].append(line[1])
elif line[3] == "link":
interface["inet6link"].append(line[1])
else:
logging.warning("unknown scope: %s" % line[3])
if status:
logging.warning("nonzero exist status (%s) for cmd: %s", status, args)
self._addr[ifname] = interface
return interface
class LxcNode(CoreNode):
apitype = NodeTypes.LXC.value
def __init__(self, session, _id=None, name=None, nodedir=None, bootsh="boot.sh", start=True, image=None):
"""
Create a LxcNode instance.
:param core.emulator.session.Session session: core session instance
:param int _id: object id
:param str name: object name
:param str nodedir: node directory
:param str bootsh: boot shell to use
:param bool start: start flag
:param str image: image to start container with
"""
if image is None:
image = "ubuntu"
self.image = image
super(LxcNode, self).__init__(session, _id, name, nodedir, bootsh, start)
def alive(self):
"""
Check if the node is alive.
:return: True if node is alive, False otherwise
:rtype: bool
"""
return self.client.is_alive()
def startup(self):
"""
Startup logic.
:return: nothing
"""
with self.lock:
if self.up:
raise ValueError("starting a node that is already up")
self.makenodedir()
self.client = LxdClient(self.name, self.image)
self.pid = self.client.create_container()
self.up = True
def shutdown(self):
"""
Shutdown logic.
:return: nothing
"""
# nothing to do if node is not up
if not self.up:
return
with self.lock:
self._netif.clear()
self.client.stop_container()
self.up = False
def cmd(self, args, wait=True):
"""
Runs shell command on node, with option to not wait for a result.
:param list[str]|str args: command to run
:param bool wait: wait for command to exit, defaults to True
:return: exit status for command
:rtype: int
"""
return self.client.cmd(args, wait)
def cmd_output(self, args):
"""
Runs shell command on node and get exit status and output.
:param list[str]|str args: command to run
:return: exit status and combined stdout and stderr
:rtype: tuple[int, str]
"""
return self.client.cmd_output(args)
def check_cmd(self, args):
"""
Runs shell command on node.
:param list[str]|str args: command to run
:return: combined stdout and stderr
:rtype: str
:raises CoreCommandError: when a non-zero exit status occurs
"""
status, output = self.client.cmd_output(args)
if status:
raise CoreCommandError(status, args, output)
return output
def network_cmd(self, args):
if not self.up:
logging.debug("node down, not running network command: %s", args)
return 0
return self.check_cmd(args)
def termcmdstring(self, sh="/bin/sh"):
"""
Create a terminal command string.
:param str sh: shell to execute command in
:return: str
"""
return "lxc exec {name} -- bash".format(name=self.name)
def privatedir(self, path):
"""
Create a private directory.
:param str path: path to create
:return: nothing
"""
logging.info("creating node dir: %s", path)
args = "mkdir -p {path}".format(path=path)
self.check_cmd(args)
def mount(self, source, target):
"""
Create and mount a directory.
:param str source: source directory to mount
:param str target: target directory to create
:return: nothing
:raises CoreCommandError: when a non-zero exit status occurs
"""
logging.info("mounting source(%s) target(%s)", source, target)
raise Exception("not supported")
def nodefile(self, filename, contents, mode=0o644):
"""
Create a node file with a given mode.
:param str filename: name of file to create
:param contents: contents of file
:param int mode: mode for file
:return: nothing
"""
logging.info("node dir(%s) ctrlchannel(%s)", self.nodedir, self.ctrlchnlname)
logging.info("nodefile filename(%s) mode(%s)", filename, mode)
file_path = os.path.join(self.nodedir, filename)
with open(file_path, "w") as f:
os.chmod(f.name, mode)
f.write(contents)
self.client.copy_file(file_path, filename)
def nodefilecopy(self, filename, srcfilename, mode=None):
"""
Copy a file to a node, following symlinks and preserving metadata.
Change file mode if specified.
:param str filename: file name to copy file to
:param str srcfilename: file to copy
:param int mode: mode to copy to
:return: nothing
"""
logging.info("node file copy file(%s) source(%s) mode(%s)", filename, srcfilename, mode)
raise Exception("not supported")
def addnetif(self, netif, ifindex):
super(LxcNode, self).addnetif(netif, ifindex)
# adding small delay to allow time for adding addresses to work correctly
time.sleep(0.5)