homeserver/ansible_collections/community/general/plugins/connection/lxc.py
2022-04-01 18:57:35 +02:00

229 lines
8 KiB
Python

# -*- coding: utf-8 -*-
# (c) 2015, Joerg Thalheim <joerg@higgsboson.tk>
# Copyright (c) 2017 Ansible Project
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
DOCUMENTATION = '''
author: Joerg Thalheim (!UNKNOWN) <joerg@higgsboson.tk>
name: lxc
short_description: Run tasks in lxc containers via lxc python library
description:
- Run commands or put/fetch files to an existing lxc container using lxc python library
options:
remote_addr:
description:
- Container identifier
default: inventory_hostname
vars:
- name: ansible_host
- name: ansible_lxc_host
executable:
default: /bin/sh
description:
- Shell executable
vars:
- name: ansible_executable
- name: ansible_lxc_executable
'''
import os
import shutil
import traceback
import select
import fcntl
import errno
HAS_LIBLXC = False
try:
import lxc as _lxc
HAS_LIBLXC = True
except ImportError:
pass
from ansible import errors
from ansible.module_utils.common.text.converters import to_bytes, to_native
from ansible.plugins.connection import ConnectionBase
class Connection(ConnectionBase):
""" Local lxc based connections """
transport = 'community.general.lxc'
has_pipelining = True
default_user = 'root'
def __init__(self, play_context, new_stdin, *args, **kwargs):
super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs)
self.container_name = self._play_context.remote_addr
self.container = None
def _connect(self):
""" connect to the lxc; nothing to do here """
super(Connection, self)._connect()
if not HAS_LIBLXC:
msg = "lxc bindings for python2 are not installed"
raise errors.AnsibleError(msg)
if self.container:
return
self._display.vvv("THIS IS A LOCAL LXC DIR", host=self.container_name)
self.container = _lxc.Container(self.container_name)
if self.container.state == "STOPPED":
raise errors.AnsibleError("%s is not running" % self.container_name)
@staticmethod
def _communicate(pid, in_data, stdin, stdout, stderr):
buf = {stdout: [], stderr: []}
read_fds = [stdout, stderr]
if in_data:
write_fds = [stdin]
else:
write_fds = []
while len(read_fds) > 0 or len(write_fds) > 0:
try:
ready_reads, ready_writes, dummy = select.select(read_fds, write_fds, [])
except select.error as e:
if e.args[0] == errno.EINTR:
continue
raise
for fd in ready_writes:
in_data = in_data[os.write(fd, in_data):]
if len(in_data) == 0:
write_fds.remove(fd)
for fd in ready_reads:
data = os.read(fd, 32768)
if not data:
read_fds.remove(fd)
buf[fd].append(data)
(pid, returncode) = os.waitpid(pid, 0)
return returncode, b"".join(buf[stdout]), b"".join(buf[stderr])
def _set_nonblocking(self, fd):
flags = fcntl.fcntl(fd, fcntl.F_GETFL) | os.O_NONBLOCK
fcntl.fcntl(fd, fcntl.F_SETFL, flags)
return fd
def exec_command(self, cmd, in_data=None, sudoable=False):
""" run a command on the chroot """
super(Connection, self).exec_command(cmd, in_data=in_data, sudoable=sudoable)
# python2-lxc needs bytes. python3-lxc needs text.
executable = to_native(self._play_context.executable, errors='surrogate_or_strict')
local_cmd = [executable, '-c', to_native(cmd, errors='surrogate_or_strict')]
read_stdout, write_stdout = None, None
read_stderr, write_stderr = None, None
read_stdin, write_stdin = None, None
try:
read_stdout, write_stdout = os.pipe()
read_stderr, write_stderr = os.pipe()
kwargs = {
'stdout': self._set_nonblocking(write_stdout),
'stderr': self._set_nonblocking(write_stderr),
'env_policy': _lxc.LXC_ATTACH_CLEAR_ENV
}
if in_data:
read_stdin, write_stdin = os.pipe()
kwargs['stdin'] = self._set_nonblocking(read_stdin)
self._display.vvv("EXEC %s" % (local_cmd), host=self.container_name)
pid = self.container.attach(_lxc.attach_run_command, local_cmd, **kwargs)
if pid == -1:
msg = "failed to attach to container %s" % self.container_name
raise errors.AnsibleError(msg)
write_stdout = os.close(write_stdout)
write_stderr = os.close(write_stderr)
if read_stdin:
read_stdin = os.close(read_stdin)
return self._communicate(pid,
in_data,
write_stdin,
read_stdout,
read_stderr)
finally:
fds = [read_stdout,
write_stdout,
read_stderr,
write_stderr,
read_stdin,
write_stdin]
for fd in fds:
if fd:
os.close(fd)
def put_file(self, in_path, out_path):
''' transfer a file from local to lxc '''
super(Connection, self).put_file(in_path, out_path)
self._display.vvv("PUT %s TO %s" % (in_path, out_path), host=self.container_name)
in_path = to_bytes(in_path, errors='surrogate_or_strict')
out_path = to_bytes(out_path, errors='surrogate_or_strict')
if not os.path.exists(in_path):
msg = "file or module does not exist: %s" % in_path
raise errors.AnsibleFileNotFound(msg)
try:
src_file = open(in_path, "rb")
except IOError:
traceback.print_exc()
raise errors.AnsibleError("failed to open input file to %s" % in_path)
try:
def write_file(args):
with open(out_path, 'wb+') as dst_file:
shutil.copyfileobj(src_file, dst_file)
try:
self.container.attach_wait(write_file, None)
except IOError:
traceback.print_exc()
msg = "failed to transfer file to %s" % out_path
raise errors.AnsibleError(msg)
finally:
src_file.close()
def fetch_file(self, in_path, out_path):
''' fetch a file from lxc to local '''
super(Connection, self).fetch_file(in_path, out_path)
self._display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self.container_name)
in_path = to_bytes(in_path, errors='surrogate_or_strict')
out_path = to_bytes(out_path, errors='surrogate_or_strict')
try:
dst_file = open(out_path, "wb")
except IOError:
traceback.print_exc()
msg = "failed to open output file %s" % out_path
raise errors.AnsibleError(msg)
try:
def write_file(args):
try:
with open(in_path, 'rb') as src_file:
shutil.copyfileobj(src_file, dst_file)
finally:
# this is needed in the lxc child process
# to flush internal python buffers
dst_file.close()
try:
self.container.attach_wait(write_file, None)
except IOError:
traceback.print_exc()
msg = "failed to transfer file from %s to %s" % (in_path, out_path)
raise errors.AnsibleError(msg)
finally:
dst_file.close()
def close(self):
''' terminate the connection; nothing to do here '''
super(Connection, self).close()
self._connected = False