from paramiko.ssh_exception import SSHException
from scp import SCPClient
from robot.api import logger
-from robot.utils.asserts import assert_equal
__all__ = ["exec_cmd", "exec_cmd_no_error"]
"""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.
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.
chan.set_combine_stderr(True)
buf = ''
- while not buf.endswith((":~$ ", "~]$ ", "~]# ")):
+ while not buf.endswith((":~# ", ":~$ ", "~]$ ", "~]# ")):
try:
chunk = chan.recv(self.__MAX_RECV_BUF)
if not chunk:
"""
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!
raise TypeError('Node parameter is None')
if cmd is None:
raise TypeError('Command parameter is None')
- if len(cmd) == 0:
+ if not cmd:
raise ValueError('Empty command parameter')
ssh = SSH()
return ret_code, stdout, stderr
-def exec_cmd_no_error(node, cmd, timeout=600, sudo=False):
+def exec_cmd_no_error(node, cmd, timeout=600, sudo=False, message=None):
"""Convenience function to ssh/exec/return out & err.
Verifies that return code is zero.
- Returns (stdout, stderr).
+ :param node: DUT node.
+ :param cmd: Command to be executed.
+ :param timeout: Timeout value in seconds. Default: 600.
+ :param sudo: Sudo privilege execution flag. Default: False.
+ :param message: Error message in case of failure. Default: None.
+ :type node: dict
+ :type cmd: str
+ :type timeout: int
+ :type sudo: bool
+ :type message: str
+ :returns: Stdout, Stderr.
+ :rtype: tuple(str, str)
+ :raise RuntimeError: If bash return code is not 0.
"""
- (ret_code, stdout, stderr) = exec_cmd(node, cmd, timeout=timeout, sudo=sudo)
- assert_equal(ret_code, 0, 'Command execution failed: "{}"\n{}'.
- format(cmd, stderr))
+ ret_code, stdout, stderr = exec_cmd(node, cmd, timeout=timeout, sudo=sudo)
+ msg = ('Command execution failed: "{cmd}"\n{stderr}'.
+ format(cmd=cmd, stderr=stderr) if message is None else message)
+ if ret_code != 0:
+ raise RuntimeError(msg)
+
return stdout, stderr