#
# Copyright (C) 2010-2017 Samuel Abels
# The MIT License (MIT)
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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"""
Decorators for callbacks passed to Queue.run().
"""
from __future__ import absolute_import
from .impl import add_label, get_label, copy_labels
from ..protocols.exception import LoginFailure
[docs]def bind(function, *args, **kwargs):
"""
Wraps the given function such that when it is called, the given arguments
are passed in addition to the connection argument.
:type function: function
:param function: The function that's ought to be wrapped.
:type args: list
:param args: Passed on to the called function.
:type kwargs: dict
:param kwargs: Passed on to the called function.
:rtype: function
:return: The wrapped function.
"""
def decorated(*inner_args, **inner_kwargs):
kwargs.update(inner_kwargs)
return function(*(inner_args + args), **kwargs)
copy_labels(function, decorated)
return decorated
[docs]def os_function_mapper(map):
"""
When called with an open connection, this function uses the
conn.guess_os() function to guess the operating system
of the connected host.
It then uses the given map to look up a function name that corresponds
to the operating system, and calls it. Example::
def ios_xr(job, host, conn):
pass # Do something.
def junos(job, host, conn):
pass # Do something else.
def shell(job, host, conn):
pass # Do something else.
Exscript.util.start.quickrun('myhost', os_function_mapper(globals()))
An exception is raised if a matching function is not found in the map.
:type conn: Exscript.protocols.Protocol
:param conn: The open connection.
:type map: dict
:param map: A dictionary mapping operating system name to a function.
:type args: list
:param args: Passed on to the called function.
:type kwargs: dict
:param kwargs: Passed on to the called function.
:rtype: object
:return: The return value of the called function.
"""
def decorated(job, host, conn, *args, **kwargs):
os = conn.guess_os()
func = map.get(os)
if func is None:
raise Exception('No handler for %s found.' % os)
return func(job, host, conn, *args, **kwargs)
return decorated
def _decorate(flush=True, attempts=1, only_authenticate=False):
"""
Wraps the given function such that conn.login() or conn.authenticate() is
executed.
Doing the real work for autologin and autoauthenticate to minimize code
duplication.
:type flush: bool
:param flush: Whether to flush the last prompt from the buffer.
:type attempts: int
:param attempts: The number of login attempts if login fails.
:type only_authenticate: bool
:param only_authenticate: login or only authenticate (don't authorize)?
:rtype: function
:return: The wrapped function.
"""
def decorator(function):
def decorated(job, host, conn, *args, **kwargs):
failed = 0
while True:
try:
if only_authenticate:
conn.authenticate(flush=flush)
else:
conn.login(flush=flush)
except LoginFailure as e:
failed += 1
if failed >= attempts:
raise
continue
break
return function(job, host, conn, *args, **kwargs)
copy_labels(function, decorated)
return decorated
return decorator
[docs]def autologin(flush=True, attempts=1):
"""
Wraps the given function such that conn.login() is executed
before calling it. Example::
@autologin(attempts = 2)
def my_func(job, host, conn):
pass # Do something.
Exscript.util.start.quickrun('myhost', my_func)
:type flush: bool
:param flush: Whether to flush the last prompt from the buffer.
:type attempts: int
:param attempts: The number of login attempts if login fails.
:rtype: function
:return: The wrapped function.
"""
return _decorate(flush, attempts)
[docs]def autoauthenticate(flush=True, attempts=1):
"""
Wraps the given function such that conn.authenticate() is executed
before calling it. Example::
@autoauthenticate(attempts = 2)
def my_func(job, host, conn):
pass # Do something.
Exscript.util.start.quickrun('myhost', my_func)
:type flush: bool
:param flush: Whether to flush the last prompt from the buffer.
:type attempts: int
:param attempts: The number of login attempts if login fails.
:rtype: function
:return: The wrapped function.
"""
return _decorate(flush, attempts, only_authenticate=True)