# Path: shakedown/dcos/helpers.py
# def validate_key(key_path):
#     """ Validate a key
# 
#         :param key_path: path to a key to use for authentication
#         :type key_path: str
# 
#         :return: key object used for authentication
#         :rtype: paramiko.RSAKey
#     """
# 
#     key_path = os.path.expanduser(key_path)
# 
#     if not os.path.isfile(key_path):
#         return False
# 
#     return paramiko.RSAKey.from_private_key_file(key_path)
# 
# def try_close(obj):
#     try:
#         obj.close()
#     except:
#         pass
# 
# def get_transport(host, username, key):
#     """ Create a transport object
# 
#         :param host: the hostname to connect to
#         :type host: str
#         :param username: SSH username
#         :type username: str
#         :param key: key object used for authentication
#         :type key: paramiko.RSAKey
# 
#         :return: a transport object
#         :rtype: paramiko.Transport
#     """
# 
#     if host == shakedown.master_ip():
#         transport = paramiko.Transport(host)
#     else:
#         transport_master = paramiko.Transport(shakedown.master_ip())
#         transport_master = start_transport(transport_master, username, key)
# 
#         if not transport_master.is_authenticated():
#             print("error: unable to authenticate {}@{} with key {}".format(username, shakedown.master_ip(), key))
#             return False
# 
#         try:
#             channel = transport_master.open_channel('direct-tcpip', (host, 22), ('127.0.0.1', 0))
#         except paramiko.SSHException:
#             print("error: unable to connect to {}".format(host))
#             return False
# 
#         transport = paramiko.Transport(channel)
# 
#     return transport
# 
# def start_transport(transport, username, key):
#     """ Begin a transport client and authenticate it
# 
#         :param transport: the transport object to start
#         :type transport: paramiko.Transport
#         :param username: SSH username
#         :type username: str
#         :param key: key object used for authentication
#         :type key: paramiko.RSAKey
# 
#         :return: the transport object passed
#         :rtype: paramiko.Transport
#     """
# 
#     transport.start_client()
# 
#     agent = paramiko.agent.Agent()
#     keys = itertools.chain((key,) if key else (), agent.get_keys())
#     for test_key in keys:
#         try:
#             transport.auth_publickey(username, test_key)
#             break
#         except paramiko.AuthenticationException as e:
#             pass
#     else:
#         raise ValueError('No valid key supplied')
# 
#     return transport


import shlex
import subprocess
import time
import paramiko
import shakedown
from _thread import RLock
from functools import wraps
from select import select
from dcos.errors import DCOSException
from .helpers import validate_key, try_close, get_transport, start_transport
        self.session = None
    
    def __enter__(self):
        """
        :return: this session manager
        :rtype: HostSession
        """
        c = _get_connection(self.host, self.username, self.key_path)
        if c:
            self.session = c.open_session()
        
        return self
    
    def __exit__(self, *args):
        """Executed when the context manager is complete.

        :return: None
        """
        self.exit_code = self.session.recv_exit_status()
        self._wait_for_recv()
        # read data that is ready
        while self.session.recv_ready():
            # lists of file descriptors that are ready for IO
            # read, write, "exceptional condition" (?)
            rl, wl, xl = select([self.session], [], [], 0.0)
            if len(rl) > 0:
                recv = str(self.session.recv(1024), "utf-8")
                if self.verbose:
                    print(recv, end='', flush=True)
                self.output += recv

# Path: shakedown/dcos/helpers.py
# def validate_key(key_path):
#     """ Validate a key
# 
#         :param key_path: path to a key to use for authentication
#         :type key_path: str
# 
#         :return: key object used for authentication
#         :rtype: paramiko.RSAKey
#     """
# 
#     key_path = os.path.expanduser(key_path)
# 
#     if not os.path.isfile(key_path):
#         return False
# 
#     return paramiko.RSAKey.from_private_key_file(key_path)
# 
# def try_close(obj):
#     try:
#         obj.close()
#     except:
#         pass
# 
# def get_transport(host, username, key):
#     """ Create a transport object
# 
#         :param host: the hostname to connect to
#         :type host: str
#         :param username: SSH username
#         :type username: str
#         :param key: key object used for authentication
#         :type key: paramiko.RSAKey
# 
#         :return: a transport object
#         :rtype: paramiko.Transport
#     """
# 
#     if host == shakedown.master_ip():
#         transport = paramiko.Transport(host)
#     else:
#         transport_master = paramiko.Transport(shakedown.master_ip())
#         transport_master = start_transport(transport_master, username, key)
# 
#         if not transport_master.is_authenticated():
#             print("error: unable to authenticate {}@{} with key {}".format(username, shakedown.master_ip(), key))
#             return False
# 
#         try:
#             channel = transport_master.open_channel('direct-tcpip', (host, 22), ('127.0.0.1', 0))
#         except paramiko.SSHException:
#             print("error: unable to connect to {}".format(host))
#             return False
# 
#         transport = paramiko.Transport(channel)
# 
#     return transport
# 
# def start_transport(transport, username, key):
#     """ Begin a transport client and authenticate it
# 
#         :param transport: the transport object to start
#         :type transport: paramiko.Transport
#         :param username: SSH username
#         :type username: str
#         :param key: key object used for authentication
#         :type key: paramiko.RSAKey
# 
#         :return: the transport object passed
#         :rtype: paramiko.Transport
#     """
# 
#     transport.start_client()
# 
#     agent = paramiko.agent.Agent()
#     keys = itertools.chain((key,) if key else (), agent.get_keys())
#     for test_key in keys:
#         try:
#             transport.auth_publickey(username, test_key)
#             break
#         except paramiko.AuthenticationException as e:
#             pass
#     else:
#         raise ValueError('No valid key supplied')
# 
#     return transport


# Path: shakedown/dcos/command.py
import shlex
import subprocess
import time
import paramiko
import shakedown
from _thread import RLock
from functools import wraps
from select import select
from dcos.errors import DCOSException
from .helpers import validate_key, try_close, get_transport, start_transport

        self.session = None
    
    def __enter__(self):
        """
        :return: this session manager
        :rtype: HostSession
        """
        c = _get_connection(self.host, self.username, self.key_path)
        if c:
            self.session = c.open_session()
        
        return self
    
    def __exit__(self, *args):
        """Executed when the context manager is complete.

        :return: None
        """
        self.exit_code = self.session.recv_exit_status()
        self._wait_for_recv()
        # read data that is ready
        while self.session.recv_ready():
            # lists of file descriptors that are ready for IO
            # read, write, "exceptional condition" (?)
            rl, wl, xl = select([self.session], [], [], 0.0)
            if len(rl) > 0:
                recv = str(self.session.recv(1024), "utf-8")
                if self.verbose:
                    print(recv, end='', flush=True)
                self.output += recv

        try_close(self.session)