def exec_command_on_vm(self, command, user, password, vm):
"""Execute the specified command on the instance.
Note that this method is reading whole command outputs to memory, thus
shouldn't be used for large outputs.
:returns: data read from standard output of the command.
:raises: SSHExecCommandFailed if command returns nonzero
status. The exception contains command status stderr content.
"""
ssh = self._get_ssh_connection()
_intermediate_transport = ssh.get_transport()
_intermediate_channel = \
_intermediate_transport.open_channel('direct-tcpip',
(vm, 22),
(self.host, 0))
transport = paramiko.Transport(_intermediate_channel)
transport.start_client()
transport.auth_password(user, password)
channel = transport.open_session()
channel.exec_command(command)
exit_status = channel.recv_exit_status()
channel.shutdown_write()
out_data = []
err_data = []
LOG.debug("Run cmd {0} on vm {1}".format(command, vm))
select_params = [channel], [], [], self.channel_timeout
while True:
ready = select.select(*select_params)
if not any(ready):
raise exceptions.TimeoutException(
"Command: '{0}' executed on host '{1}'.".format(
command, self.host))
if not ready[0]: # If there is nothing to read.
continue
out_chunk = err_chunk = None
if channel.recv_ready():
out_chunk = channel.recv(self.buf_size)
out_data += out_chunk,
if channel.recv_stderr_ready():
err_chunk = channel.recv_stderr(self.buf_size)
err_data += err_chunk,
if channel.closed and not err_chunk and not out_chunk:
break
if 0 != exit_status:
LOG.warning(
'Command {0} finishes with non-zero exit code {1}'.format(
command, exit_status))
raise exceptions.SSHExecCommandFailed(
command=command,
exit_status=exit_status,
strerror=''.join(err_data).join(out_data))
LOG.debug('Current result {0} {1} {2}'.format(command, err_data,
out_data))
return ''.join(out_data)
def exec_command(self, cmd):
"""
Execute the specified command on the server.
Note that this method is reading whole command outputs to memory, thus
shouldn't be used for large outputs.
:returns: data read from standard output of the command.
:raises: SSHExecCommandFailed if command returns nonzero
status. The exception contains command status stderr content.
"""
ssh = self._get_ssh_connection()
transport = ssh.get_transport()
channel = transport.open_session()
channel.get_pty()
channel.fileno() # Register event pipe
channel.exec_command(cmd)
channel.shutdown_write()
out_data = []
err_data = []
select_params = [channel], [], [], self.channel_timeout
while True:
ready = select.select(*select_params)
if not any(ready):
raise exceptions.TimeoutException(
"Command: '{0}' executed on host '{1}'.".format(
cmd, self.host))
if not ready[0]: # If there is nothing to read.
continue
out_chunk = err_chunk = None
if channel.recv_ready():
out_chunk = channel.recv(self.buf_size)
out_data += out_chunk,
if channel.recv_stderr_ready():
err_chunk = channel.recv_stderr(self.buf_size)
err_data += err_chunk,
if channel.closed and not err_chunk and not out_chunk:
break
exit_status = channel.recv_exit_status()
if 0 != exit_status:
raise exceptions.SSHExecCommandFailed(
command=cmd,
exit_status=exit_status,
strerror=''.join(err_data).join(out_data))
return ''.join(out_data)