-# Copyright (c) 2016 Cisco and/or its affiliates.
+# Copyright (c) 2018 Cisco and/or its affiliates.
# 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:
:param node: Node in topology.
:type node: dict
- :return: IP address and port for the specified node.
+ :returns: IP address and port for the specified node.
:rtype: int
"""
"""Connect to node prior to running exec_command or scp.
If there already is a connection to the node, this method reuses it.
+
+ :param node: Node in topology.
+ :param attempts: Number of reconnect attempts.
+ :type node: dict
+ :type attempts: int
+ :raises IOError: If cannot connect to host.
"""
- try:
- self._node = node
- node_hash = self._node_hash(node)
- if node_hash in SSH.__existing_connections:
- self._ssh = SSH.__existing_connections[node_hash]
- logger.debug('reusing ssh: {0}'.format(self._ssh))
+ self._node = node
+ node_hash = self._node_hash(node)
+ if node_hash in SSH.__existing_connections:
+ self._ssh = SSH.__existing_connections[node_hash]
+ if self._ssh.get_transport().is_active():
+ logger.debug('Reusing SSH: {ssh}'.format(ssh=self._ssh))
else:
+ if attempts > 0:
+ self._reconnect(attempts-1)
+ else:
+ raise IOError('Cannot connect to {host}'.
+ format(host=node['host']))
+ else:
+ try:
start = time()
pkey = None
if 'priv_key' in node:
self._ssh.get_transport().set_keepalive(10)
SSH.__existing_connections[node_hash] = self._ssh
-
- logger.trace('connect took {} seconds'.format(time() - start))
- logger.debug('new ssh: {0}'.format(self._ssh))
-
- logger.debug('Connect peer: {0}'.
- format(self._ssh.get_transport().getpeername()))
- logger.debug('Connections: {0}'.
- format(str(SSH.__existing_connections)))
- except:
- if attempts > 0:
- self._reconnect(attempts-1)
- else:
- raise
+ logger.debug('New SSH to {peer} took {total} seconds: {ssh}'.
+ format(
+ peer=self._ssh.get_transport().getpeername(),
+ total=(time() - start),
+ ssh=self._ssh))
+ except SSHException:
+ raise IOError('Cannot connect to {host}'.
+ format(host=node['host']))
def disconnect(self, node):
"""Close SSH connection to the node.
"""
node_hash = self._node_hash(node)
if node_hash in SSH.__existing_connections:
- logger.debug('Disconnecting peer: {}, {}'.
- format(node['host'], node['port']))
+ logger.debug('Disconnecting peer: {host}, {port}'.
+ format(host=node['host'], port=node['port']))
ssh = SSH.__existing_connections.pop(node_hash)
ssh.close()
def _reconnect(self, attempts=0):
- """Close the SSH connection and open it again."""
+ """Close the SSH connection and open it again.
+ :param attempts: Number of reconnect attempts.
+ :type attempts: int
+ """
node = self._node
self.disconnect(node)
self.connect(node, attempts)
- logger.debug('Reconnecting peer done: {}'.
- format(self._ssh.get_transport().getpeername()))
+ logger.debug('Reconnecting peer done: {host}, {port}'.
+ format(host=node['host'], port=node['port']))
def exec_command(self, cmd, timeout=10):
"""Execute SSH command on a new channel on the connected Node.
stderr = StringIO.StringIO()
try:
chan = self._ssh.get_transport().open_session(timeout=5)
+ peer = self._ssh.get_transport().getpeername()
except AttributeError:
self._reconnect()
chan = self._ssh.get_transport().open_session(timeout=5)
+ peer = self._ssh.get_transport().getpeername()
except SSHException:
self._reconnect()
chan = self._ssh.get_transport().open_session(timeout=5)
+ peer = self._ssh.get_transport().getpeername()
chan.settimeout(timeout)
- logger.trace('exec_command on {0}: {1}'
- .format(self._ssh.get_transport().getpeername(), cmd))
+
+ logger.trace('exec_command on {peer} with timeout {timeout}: {cmd}'
+ .format(peer=peer, timeout=timeout, cmd=cmd))
start = time()
chan.exec_command(cmd)
if time() - start > timeout:
raise SSHTimeout(
- 'Timeout exception during execution of command: {0}\n'
- 'Current contents of stdout buffer: {1}\n'
- 'Current contents of stderr buffer: {2}\n'
- .format(cmd, stdout.getvalue(), stderr.getvalue())
+ 'Timeout exception during execution of command: {cmd}\n'
+ 'Current contents of stdout buffer: {stdout}\n'
+ 'Current contents of stderr buffer: {stderr}\n'
+ .format(cmd=cmd, stdout=stdout.getvalue(),
+ stderr=stderr.getvalue())
)
sleep(0.1)
stderr.write(chan.recv_stderr(self.__MAX_RECV_BUF))
end = time()
- logger.trace('exec_command on {0} took {1} seconds'.format(
- self._ssh.get_transport().getpeername(), end-start))
+ logger.trace('exec_command on {peer} took {total} seconds'.
+ format(peer=peer, total=end-start))
- logger.trace('return RC {}'.format(return_code))
- logger.trace('return STDOUT {}'.format(stdout.getvalue()))
- logger.trace('return STDERR {}'.format(stderr.getvalue()))
+ logger.trace('return RC {rc}'.format(rc=return_code))
+ logger.trace('return STDOUT {stdout}'.format(stdout=stdout.getvalue()))
+ logger.trace('return STDERR {stderr}'.format(stderr=stderr.getvalue()))
return return_code, stdout.getvalue(), stderr.getvalue()
def exec_command_sudo(self, cmd, cmd_input=None, timeout=30):
:param cmd: Command to be executed.
:param cmd_input: Input redirected to the command.
:param timeout: Timeout.
- :return: return_code, stdout, stderr
+ :returns: return_code, stdout, stderr
:Example:
:type lxc_params: str
:type sudo: bool
:type timeout: int
- :return: return_code, stdout, stderr
+ :returns: return_code, stdout, stderr
"""
command = "lxc-attach {p} --name {n} -- /bin/sh -c '{c}'"\
.format(p=lxc_params, n=lxc_name, c=lxc_cmd)
command = 'sudo -S {c}'.format(c=command)
return self.exec_command(command, timeout)
- def interactive_terminal_open(self, time_out=30):
+ def interactive_terminal_open(self, time_out=45):
"""Open interactive terminal on a new channel on the connected Node.
:param time_out: Timeout in seconds.
- :return: SSH channel with opened terminal.
+ :returns: SSH channel with opened terminal.
.. warning:: Interruptingcow is used here, and it uses
signal(SIGALRM) to let the operating system interrupt program
:param cmd: Command to be executed.
:param prompt: Command prompt, sequence of characters used to
indicate readiness to accept commands.
- :return: Command output.
+ :returns: Command output.
.. warning:: Interruptingcow is used here, and it uses
signal(SIGALRM) to let the operating system interrupt program
"""
chan.close()
- def scp(self, local_path, remote_path, get=False, timeout=10):
+ def scp(self, local_path, remote_path, get=False, timeout=30):
"""Copy files from local_path to remote_path or vice versa.
connect() method has to be called first!