Source code for airflow.contrib.operators.ssh_operator

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from base64 import b64encode
from select import select

from airflow import configuration
from airflow.contrib.hooks.ssh_hook import SSHHook
from airflow.exceptions import AirflowException
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults


[docs]class SSHOperator(BaseOperator): """ SSHOperator to execute commands on given remote host using the ssh_hook. :param ssh_hook: predefined ssh_hook to use for remote execution :type ssh_hook: :class:`SSHHook` :param ssh_conn_id: connection id from airflow Connections :type ssh_conn_id: str :param remote_host: remote host to connect :type remote_host: str :param command: command to execute on remote host. (templated) :type command: str :param timeout: timeout (in seconds) for executing the command. :type timeout: int :param do_xcom_push: return the stdout which also get set in xcom by airflow platform :type do_xcom_push: bool """ template_fields = ('command',) template_ext = ('.sh',) @apply_defaults def __init__(self, ssh_hook=None, ssh_conn_id=None, remote_host=None, command=None, timeout=10, do_xcom_push=False, *args, **kwargs): super(SSHOperator, self).__init__(*args, **kwargs) self.ssh_hook = ssh_hook self.ssh_conn_id = ssh_conn_id self.remote_host = remote_host self.command = command self.timeout = timeout self.do_xcom_push = do_xcom_push def execute(self, context): try: if self.ssh_conn_id and not self.ssh_hook: self.ssh_hook = SSHHook(ssh_conn_id=self.ssh_conn_id) if not self.ssh_hook: raise AirflowException("can not operate without ssh_hook or ssh_conn_id") if self.remote_host is not None: self.ssh_hook.remote_host = self.remote_host ssh_client = self.ssh_hook.get_conn() if not self.command: raise AirflowException("no command specified so nothing to execute here.") # Auto apply tty when its required in case of sudo get_pty = False if self.command.startswith('sudo'): get_pty = True # set timeout taken as params stdin, stdout, stderr = ssh_client.exec_command(command=self.command, get_pty=get_pty, timeout=self.timeout ) # get channels channel = stdout.channel # closing stdin stdin.close() channel.shutdown_write() agg_stdout = b'' agg_stderr = b'' # capture any initial output in case channel is closed already stdout_buffer_length = len(stdout.channel.in_buffer) if stdout_buffer_length > 0: agg_stdout += stdout.channel.recv(stdout_buffer_length) # read from both stdout and stderr while not channel.closed or \ channel.recv_ready() or \ channel.recv_stderr_ready(): readq, _, _ = select([channel], [], [], self.timeout) for c in readq: if c.recv_ready(): line = stdout.channel.recv(len(c.in_buffer)) line = line agg_stdout += line self.log.info(line.decode('utf-8').strip('\n')) if c.recv_stderr_ready(): line = stderr.channel.recv_stderr(len(c.in_stderr_buffer)) line = line agg_stderr += line self.log.warning(line.decode('utf-8').strip('\n')) if stdout.channel.exit_status_ready()\ and not stderr.channel.recv_stderr_ready()\ and not stdout.channel.recv_ready(): stdout.channel.shutdown_read() stdout.channel.close() break stdout.close() stderr.close() exit_status = stdout.channel.recv_exit_status() if exit_status is 0: # returning output if do_xcom_push is set if self.do_xcom_push: enable_pickling = configuration.conf.getboolean( 'core', 'enable_xcom_pickling' ) if enable_pickling: return agg_stdout else: return b64encode(agg_stdout).decode('utf-8') else: error_msg = agg_stderr.decode('utf-8') raise AirflowException("error running cmd: {0}, error: {1}" .format(self.command, error_msg)) except Exception as e: raise AirflowException("SSH operator error: {0}".format(str(e))) return True def tunnel(self): ssh_client = self.ssh_hook.get_conn() ssh_client.get_transport()