Misc cleanups and some fixes for docker connection plugin

* Remove extraneous imports
* Fix some error handling
* Enable pipelining
* Disable su since it doesn't work
* Add error message when installed docker is not recent enough to
  support this plugin
* Move nested functions to class level
* Make transport a class attribute
* Make exec_command, put_file and fetch_file more robust
This commit is contained in:
Toshio Kuratomi 2015-09-28 22:30:53 -07:00
parent 1d119a1f46
commit 0e110d23f8

View file

@ -23,20 +23,26 @@
import os
import subprocess
import time
import re
from distutils.version import LooseVersion
import ansible.constants as C
from ansible import errors
from ansible.errors import AnsibleError, AnsibleFileNotFound
from ansible.plugins.connection import ConnectionBase
BUFSIZE = 65536
class Connection(ConnectionBase):
has_pipelining = True
transport = 'docker'
# su currently has an undiagnosed issue with calculating the file
# checksums (so copy, for instance, doesn't work right)
# Have to look into that before re-enabling this
become_methods = frozenset(C.BECOME_METHODS).difference(('su',))
def __init__(self, play_context, new_stdin, *args, **kwargs):
super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs)
@ -48,21 +54,24 @@ class Connection(ConnectionBase):
self.can_copy_bothways = False
docker_version = self._get_docker_version()
if LooseVersion(docker_version) < LooseVersion('1.3'):
raise AnsibleError('docker connection type requires docker 1.3 or higher')
if LooseVersion(docker_version) >= LooseVersion('1.8.0'):
self.can_copy_bothways = True
def _get_docker_version(self):
def sanitize_version(version):
@staticmethod
def _sanitize_version(version):
return re.sub('[^0-9a-zA-Z\.]', '', version)
def _get_docker_version(self):
cmd = [self.docker_cmd, 'version']
cmd_output = subprocess.check_output(cmd)
for line in cmd_output.split('\n'):
if line.startswith('Server version:'): # old docker versions
return sanitize_version(line.split()[2])
return self._sanitize_version(line.split()[2])
# no result yet, must be newer Docker version
new_docker_cmd = [
@ -72,58 +81,46 @@ class Connection(ConnectionBase):
cmd_output = subprocess.check_output(new_docker_cmd)
return sanitize_version(cmd_output)
@property
def transport(self):
return 'docker'
return self._sanitize_version(cmd_output)
def _connect(self, port=None):
""" Connect to the container. Nothing to do """
super(Connection, self)._connect()
if not self._connected:
self._display.vvv("ESTABLISH LOCAL CONNECTION FOR USER: {0}".format(
self._play_context.remote_user, host=self._play_context.remote_addr)
)
self._connected = True
return self
def exec_command(self, cmd, in_data=None, sudoable=False):
""" Run a command on the local host """
super(Connection, self).exec_command(cmd, in_data=in_data, sudoable=sudoable)
# Don't currently support su
if in_data:
raise errors.AnsibleError("Internal Error: this module does not "
"support optimized module pipelining")
executable = C.DEFAULT_EXECUTABLE.split()[0] if C.DEFAULT_EXECUTABLE else None
if executable:
local_cmd = [self.docker_cmd, "exec", self._play_context.remote_addr, executable,
'-c', cmd]
else:
local_cmd = '%s exec "%s" %s' % (self.docker_cmd, self._play_context.remote_addr, cmd)
executable = C.DEFAULT_EXECUTABLE.split()[0] if C.DEFAULT_EXECUTABLE else '/bin/sh'
# -i is needed to keep stdin open which allows pipelining to work
local_cmd = [self.docker_cmd, "exec", '-i', self._play_context.remote_addr, executable, '-c', cmd]
self._display.vvv("EXEC %s" % (local_cmd), host=self._play_context.remote_addr)
p = subprocess.Popen(local_cmd,
shell=isinstance(local_cmd, basestring),
shell=False,
stdin=subprocess.PIPE,
stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdout, stderr = p.communicate()
stdout, stderr = p.communicate(in_data)
return (p.returncode, stdout, stderr)
# Docker doesn't have native support for copying files into running
# containers, so we use docker exec to implement this
def put_file(self, in_path, out_path):
""" Transfer a file from local to container """
if not os.path.exists(in_path):
raise errors.AnsibleFileNotFound(
"file or module does not exist: %s" % in_path)
super(Connection, self).put_file(in_path, out_path)
self._display.vvv("PUT %s TO %s" % (in_path, out_path), host=self._play_context.remote_addr)
if self.can_copy_bothways: # only docker >= 1.8.1 can do this natively
if not os.path.exists(in_path):
raise AnsibleFileNotFound(
"file or module does not exist: %s" % in_path)
if self.can_copy_bothways:
# only docker >= 1.8.1 can do this natively
args = [
self.docker_cmd,
"cp",
@ -132,22 +129,34 @@ class Connection(ConnectionBase):
]
subprocess.check_call(args)
else:
args = [self.docker_cmd, "exec", "-i", self._play_context.remote_addr, "bash", "-c",
"dd of=%s bs=%s" % (format(out_path), BUFSIZE)]
p = subprocess.Popen(args, stdin=open(in_path),
# Older docker doesn't have native support for copying files into
# running containers, so we use docker exec to implement this
executable = C.DEFAULT_EXECUTABLE.split()[0] if C.DEFAULT_EXECUTABLE else '/bin/sh'
args = [self.docker_cmd, "exec", "-i", self._play_context.remote_addr, executable, "-c",
"dd of={0} bs={1}".format(out_path, BUFSIZE)]
with open(in_path, 'rb') as in_file:
try:
p = subprocess.Popen(args, stdin=in_file,
stdout=subprocess.PIPE, stderr=subprocess.PIPE)
p.communicate()
except OSError:
raise AnsibleError("docker connection requires dd command in the chroot")
stdout, stderr = p.communicate()
if p.returncode != 0:
raise AnsibleError("failed to transfer file %s to %s:\n%s\n%s" % (in_path, out_path, stdout, stderr))
def fetch_file(self, in_path, out_path):
""" Fetch a file from container to local. """
super(Connection, self).fetch_file(in_path, out_path)
self._display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self._play_context.remote_addr)
# out_path is the final file path, but docker takes a directory, not a
# file path
out_dir = os.path.dirname(out_path)
args = [self.docker_cmd, "cp", "%s:%s" % (self._play_context.remote_addr, in_path), out_dir]
self._display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self._play_context.remote_addr)
p = subprocess.Popen(args, stdin=subprocess.PIPE,
stdout=subprocess.PIPE, stderr=subprocess.PIPE)
p.communicate()