cdist/lib/cdist/exec/remote.py
Steven Armstrong 654e19f28b mark _run_command as private
Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
2011-11-18 14:40:25 +01:00

173 lines
6 KiB
Python

# -*- coding: utf-8 -*-
#
# 2011 Steven Armstrong (steven-cdist at armstrong.cc)
# 2011 Nico Schottelius (nico-cdist at schottelius.org)
#
# This file is part of cdist.
#
# cdist is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# cdist is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with cdist. If not, see <http://www.gnu.org/licenses/>.
#
#
# FIXME: common base class with Local?
import io
import os
import sys
import subprocess
import logging
import cdist
class RemoteScriptError(cdist.Error):
def __init__(self, script, command, script_content):
self.script = script
self.command = command
self.script_content = script_content
def __str__(self):
plain_command = " ".join(self.command)
return "Remote script execution failed: %s" % plain_command
class DecodeError(cdist.Error):
def __init__(self, command):
self.command = command
def __str__(self):
return "Cannot decode output of " + " ".join(self.command)
class Remote(object):
"""Execute commands remotely.
All interaction with the remote side should be done through this class.
Directly accessing the remote side from python code is a bug.
"""
def __init__(self, target_host, remote_base_path, remote_exec, remote_copy):
self.target_host = target_host
self.base_path = remote_base_path
self._exec = remote_exec
self._copy = remote_copy
self.conf_path = os.path.join(self.base_path, "conf")
self.object_path = os.path.join(self.base_path, "object")
self.type_path = os.path.join(self.conf_path, "type")
self.global_explorer_path = os.path.join(self.conf_path, "explorer")
self.log = logging.getLogger(self.target_host)
def create_directories(self):
self.rmdir(self.base_path)
self.mkdir(self.base_path)
self.mkdir(self.conf_path)
def rmdir(self, path):
"""Remove directory on the remote side."""
self.log.debug("Remote rmdir: %s", path)
self.run(["rm", "-rf", path])
def mkdir(self, path):
"""Create directory on the remote side."""
self.log.debug("Remote mkdir: %s", path)
self.run(["mkdir", "-p", path])
def transfer(self, source, destination):
"""Transfer a file or directory to the remote side."""
self.log.debug("Remote transfer: %s -> %s", source, destination)
self.rmdir(destination)
command = self._copy.split()
command.extend(["-r", source, self.target_host + ":" + destination])
self._run_command(command)
def run(self, command, env=None, return_output=False):
"""Run the given command with the given environment on the remote side.
Return the output as a string.
"""
# prefix given command with remote_exec
cmd = self._exec.split()
cmd.append(self.target_host)
cmd.extend(command)
return self._run_command(cmd, env=env, return_output=return_output)
def _run_command(self, command, env=None, return_output=False):
"""Run the given command with the given environment.
Return the output as a string.
"""
assert isinstance(command, (list, tuple)), "list or tuple argument expected, got: %s" % command
# export target_host for use in __remote_{exec,copy} scripts
os_environ = os.environ.copy()
os_environ['__target_host'] = self.target_host
# can't pass environment to remote side, so prepend command with
# variable declarations
if env:
cmd = ["%s=%s" % item for item in env.items()]
cmd.extend(command)
else:
cmd = command
self.log.debug("Remote run: %s", command)
try:
if return_output:
return subprocess.check_output(command, env=os_environ).decode()
else:
subprocess.check_call(command, env=os_environ)
except subprocess.CalledProcessError:
raise cdist.Error("Command failed: " + " ".join(command))
except OSError as error:
raise cdist.Error(" ".join(*args) + ": " + error.args[1])
except UnicodeDecodeError:
raise DecodeError(command)
def run_script(self, script, env=None, return_output=False):
"""Run the given script with the given environment on the remote side.
Return the output as a string.
"""
command = self._exec.split()
command.append(self.target_host)
# export target_host for use in __remote_{exec,copy} scripts
os_environ = os.environ.copy()
os_environ['__target_host'] = self.target_host
# can't pass environment to remote side, so prepend command with
# variable declarations
if env:
command.extend(["%s=%s" % item for item in env.items()])
command.extend(["/bin/sh", "-e"])
command.append(script)
self.log.debug("Remote run script: %s", command)
if env:
self.log.debug("Remote run script env: %s", env)
try:
if return_output:
return subprocess.check_output(command, env=os_environ).decode()
else:
subprocess.check_call(command, env=os_environ)
except subprocess.CalledProcessError as error:
script_content = self.run(["cat", script], return_output=True)
self.log.error("Code that raised the error:\n%s", script_content)
raise RemoteScriptError(script, command, script_content)
except EnvironmentError as error:
raise cdist.Error(" ".join(command) + ": " + error.args[1])