rally/rally/utils/sshutils.py

308 lines
11 KiB
Python

# Copyright 2013: Mirantis Inc.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""High level ssh library.
Usage examples:
Execute command and get output:
ssh = sshclient.SSH("root", "example.com", port=33)
status, stdout, stderr = ssh.execute("ps ax")
if status:
raise Exception("Command failed with non-zero status.")
print(stdout.splitlines())
Execute command with huge output:
class PseudoFile(object):
def write(chunk):
if "error" in chunk:
email_admin(chunk)
ssh = sshclient.SSH("root", "example.com")
ssh.run("tail -f /var/log/syslog", stdout=PseudoFile(), timeout=False)
Execute local script on remote side:
ssh = sshclient.SSH("user", "example.com")
status, out, err = ssh.execute("/bin/sh -s arg1 arg2",
stdin=open("~/myscript.sh", "r"))
Upload file:
ssh = sshclient.SSH("user", "example.com")
ssh.run("cat > ~/upload/file.gz", stdin=open("/store/file.gz", "rb"))
Eventlet:
eventlet.monkey_patch(select=True, time=True)
or
eventlet.monkey_patch()
or
sshclient = eventlet.import_patched("opentstack.common.sshclient")
"""
import io
import os
import select
import shlex
import socket
import time
import paramiko
from rally.common import logging
from rally import exceptions
LOG = logging.getLogger(__name__)
class SSH(object):
"""Represent ssh connection."""
def __init__(self, user, host, port=22, pkey=None,
key_filename=None, password=None):
"""Initialize SSH client.
:param user: ssh username
:param host: hostname or ip address of remote ssh server
:param port: remote ssh port
:param pkey: RSA or DSS private key string or file object
:param key_filename: private key filename
:param password: password
"""
self.user = user
self.host = host
self.port = port
self.pkey = self._get_pkey(pkey) if pkey else None
self.password = password
self.key_filename = key_filename
self._client = False
def __enter__(self):
return self
def __exit__(self, *args):
if self._client:
self.close()
def _get_pkey(self, key):
if isinstance(key, str):
key = io.StringIO(key)
errors = []
key_pos = key.seek(0, 1)
for key_class in (paramiko.rsakey.RSAKey, paramiko.dsskey.DSSKey):
try:
return key_class.from_private_key(key)
except paramiko.SSHException as e:
key.seek(key_pos)
errors.append(e)
raise exceptions.SSHError("Invalid pkey: %s" % (errors))
def _get_client(self):
if self._client:
return self._client
try:
self._client = paramiko.SSHClient()
self._client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
self._client.connect(self.host, username=self.user,
port=self.port, pkey=self.pkey,
key_filename=self.key_filename,
password=self.password, timeout=1)
return self._client
except Exception as e:
message = ("Exception %(exception_type)s was raised "
"during connect to %(user)s@%(host)s:%(port)s. "
"Exception value is: %(exception)r")
self._client = False
raise exceptions.SSHError(message % {"exception": e,
"user": self.user,
"host": self.host,
"port": self.port,
"exception_type": type(e)})
def close(self):
self._client.close()
self._client = False
def run(self, cmd, stdin=None, stdout=None, stderr=None,
raise_on_error=True, timeout=3600):
"""Execute specified command on the server.
:param cmd: Command to be executed.
:param stdin: Open file or string to pass to stdin.
:param stdout: Open file to connect to stdout.
:param stderr: Open file to connect to stderr.
:param raise_on_error: If False then exit code will be return. If True
then exception will be raised if non-zero code.
:param timeout: Timeout in seconds for command execution.
Default 1 hour. No timeout if set to 0.
"""
client = self._get_client()
should_close_stdin = False
if isinstance(stdin, str):
stdin = io.StringIO(stdin)
should_close_stdin = True
try:
return self._run(client, cmd, stdin=stdin, stdout=stdout,
stderr=stderr, raise_on_error=raise_on_error,
timeout=timeout)
finally:
if should_close_stdin:
stdin.close()
def _run(self, client, cmd, stdin=None, stdout=None, stderr=None,
raise_on_error=True, timeout=3600):
if isinstance(cmd, (list, tuple)):
cmd = " ".join(shlex.quote(str(p)) for p in cmd)
transport = client.get_transport()
session = transport.open_session()
session.exec_command(cmd)
start_time = time.time()
data_to_send = ""
stderr_data = None
# If we have data to be sent to stdin then `select' should also
# check for stdin availability.
if stdin and not stdin.closed:
writes = [session]
else:
writes = []
data = None
while True:
# Block until data can be read/write.
r, w, e = select.select([session], writes, [session], 1)
if session.recv_ready():
data = session.recv(4096)
LOG.debug("stdout: %r" % data)
if stdout is not None:
stdout.write(data.decode("utf8"))
continue
if session.recv_stderr_ready():
stderr_data = session.recv_stderr(4096)
LOG.debug("stderr: %r" % stderr_data)
if stderr is not None:
stderr.write(stderr_data.decode("utf8"))
continue
if session.send_ready():
if stdin is not None and not stdin.closed:
if not data_to_send:
data_to_send = stdin.read(4096)
if not data_to_send:
stdin.close()
session.shutdown_write()
writes = []
continue
sent_bytes = session.send(data_to_send)
LOG.debug("sent: %s" % data_to_send[:sent_bytes])
data_to_send = data_to_send[sent_bytes:]
if session.exit_status_ready():
break
if timeout and (time.time() - timeout) > start_time:
args = {"cmd": cmd, "host": self.host}
raise exceptions.SSHTimeout("Timeout executing command "
"'%(cmd)s' on host %(host)s"
% args)
if e:
raise exceptions.SSHError("Socket error.")
exit_status = session.recv_exit_status()
if 0 != exit_status and raise_on_error:
fmt = "Command '%(cmd)s' failed with exit_status %(status)d."
details = fmt % {"cmd": cmd, "status": exit_status}
if stderr_data:
details += " Last stderr data: '%s'." % stderr_data
raise exceptions.SSHError(details)
return exit_status, data
def execute(self, cmd, stdin=None, timeout=3600):
"""Execute the specified command on the server.
:param cmd: Command to be executed, can be a list.
:param stdin: Open file to be sent on process stdin.
:param timeout: Timeout for execution of the command.
:returns: tuple (exit_status, stdout, stderr)
"""
with io.StringIO() as stdout:
with io.StringIO() as stderr:
exit_status, data = self.run(cmd, stderr=stderr, stdout=stdout,
stdin=stdin, timeout=timeout,
raise_on_error=False)
stdout.seek(0)
stderr.seek(0)
return exit_status, stdout.read(), stderr.read()
def wait(self, timeout=120, interval=1):
"""Wait for the host will be available via ssh."""
start_time = time.time()
while True:
try:
return self.execute("uname")
except (socket.error, exceptions.SSHError) as e:
LOG.debug("Ssh is still unavailable: %r" % e)
time.sleep(interval)
if time.time() > (start_time + timeout):
raise exceptions.SSHTimeout("Timeout waiting for '%s'" %
self.host)
def _put_file_sftp(self, localpath, remotepath, mode=None):
client = self._get_client()
with client.open_sftp() as sftp:
sftp.put(localpath, remotepath)
if mode is None:
mode = 0o777 & os.stat(localpath).st_mode
sftp.chmod(remotepath, mode)
def _put_file_shell(self, localpath, remotepath, mode=None):
cmd = ["cat > %s" % remotepath]
if mode is not None:
cmd.append("chmod 0%o %s" % (mode, remotepath))
with open(localpath, "rb") as localfile:
cmd = "; ".join(cmd)
self.run(cmd, stdin=localfile)
def put_file(self, localpath, remotepath, mode=None):
"""Copy specified local file to the server.
:param localpath: Local filename.
:param remotepath: Remote filename.
:param mode: Permissions to set after upload
"""
import socket
try:
self._put_file_sftp(localpath, remotepath, mode=mode)
except (paramiko.SSHException, socket.error):
self._put_file_shell(localpath, remotepath, mode=mode)