Mini Shell
"""
Internal shared-state variables such as config settings and host lists.
"""
import os
import sys
from optparse import make_option
from fabric.network import HostConnectionCache, ssh
from fabric.version import get_version
from fabric.utils import _AliasDict, _AttributeDict
#
# Win32 flag
#
# Impacts a handful of platform specific behaviors. Note that Cygwin's Python
# is actually close enough to "real" UNIXes that it doesn't need (or want!) to
# use PyWin32 -- so we only test for literal Win32 setups (vanilla Python,
# ActiveState etc) here.
win32 = (sys.platform == 'win32')
#
# Environment dictionary - support structures
#
# By default, if the user (including code using Fabric as a library) doesn't
# set the username, we obtain the currently running username and use that.
def _get_system_username():
"""
Obtain name of current system user, which will be default connection user.
"""
username = None
try:
import getpass
username = getpass.getuser()
# getpass.getuser supported on both Unix and Windows systems.
# getpass.getuser may call pwd.getpwuid which in turns may raise KeyError
# if it cannot find a username for the given UID, e.g. on ep.io
# and similar "non VPS" style services. Rather than error out, just keep
# the 'default' username to None. Can check for this value later if needed.
except KeyError:
pass
except ImportError:
if win32:
import win32api
import win32security # noqa
import win32profile # noqa
username = win32api.GetUserName()
return username
def _rc_path():
"""
Return platform-specific default file path for $HOME/.fabricrc.
"""
rc_file = '.fabricrc'
rc_path = '~/' + rc_file
expanded_rc_path = os.path.expanduser(rc_path)
if expanded_rc_path == rc_path:
if win32:
from win32com.shell.shell import SHGetSpecialFolderPath
from win32com.shell.shellcon import CSIDL_PROFILE
expanded_rc_path = "%s/%s" % (
SHGetSpecialFolderPath(0, CSIDL_PROFILE),
rc_file
)
return expanded_rc_path
default_port = '22' # hurr durr
default_ssh_config_path = os.path.join(os.path.expanduser('~'), '.ssh', 'config')
# Options/settings which exist both as environment keys and which can be set on
# the command line, are defined here. When used via `fab` they will be added to
# the optparse parser, and either way they are added to `env` below (i.e. the
# 'dest' value becomes the environment key and the value, the env value).
#
# Keep in mind that optparse changes hyphens to underscores when automatically
# deriving the `dest` name, e.g. `--reject-unknown-hosts` becomes
# `reject_unknown_hosts`.
#
# Furthermore, *always* specify some sort of default to avoid ending up with
# optparse.NO_DEFAULT (currently a two-tuple)! In general, None is a better
# default than ''.
#
# User-facing documentation for these are kept in
# sites/docs/usage/env.rst and sites/docs/usage/fab.rst
env_options = [
make_option('-a', '--no_agent',
action='store_true',
default=False,
help="don't use the running SSH agent"
),
make_option('-A', '--forward-agent',
action='store_true',
default=False,
help="forward local agent to remote end"
),
make_option('--abort-on-prompts',
action='store_true',
default=False,
help="abort instead of prompting (for password, host, etc)"
),
make_option('-c', '--config',
dest='rcfile',
default=_rc_path(),
metavar='PATH',
help="specify location of config file to use"
),
make_option('--colorize-errors',
action='store_true',
default=False,
help="Color error output",
),
make_option('-D', '--disable-known-hosts',
action='store_true',
default=False,
help="do not load user known_hosts file"
),
make_option('-e', '--eagerly-disconnect',
action='store_true',
default=False,
help="disconnect from hosts as soon as possible"
),
make_option('-f', '--fabfile',
default='fabfile',
metavar='PATH',
help="python module file to import, e.g. '../other.py'"
),
make_option('-g', '--gateway',
default=None,
metavar='HOST',
help="gateway host to connect through"
),
make_option('--gss-auth',
action='store_true',
default=None,
help="Use GSS-API authentication"
),
make_option('--gss-deleg',
action='store_true',
default=None,
help="Delegate GSS-API client credentials or not"
),
make_option('--gss-kex',
action='store_true',
default=None,
help="Perform GSS-API Key Exchange and user authentication"
),
make_option('--hide',
metavar='LEVELS',
help="comma-separated list of output levels to hide"
),
make_option('-H', '--hosts',
default=[],
help="comma-separated list of hosts to operate on"
),
make_option('-i',
action='append',
dest='key_filename',
metavar='PATH',
default=None,
help="path to SSH private key file. May be repeated."
),
make_option('-k', '--no-keys',
action='store_true',
default=False,
help="don't load private key files from ~/.ssh/"
),
make_option('--keepalive',
dest='keepalive',
type=int,
default=0,
metavar="N",
help="enables a keepalive every N seconds"
),
make_option('--linewise',
action='store_true',
default=False,
help="print line-by-line instead of byte-by-byte"
),
make_option('-n', '--connection-attempts',
type='int',
metavar='M',
dest='connection_attempts',
default=1,
help="make M attempts to connect before giving up"
),
make_option('--no-pty',
dest='always_use_pty',
action='store_false',
default=True,
help="do not use pseudo-terminal in run/sudo"
),
make_option('-p', '--password',
default=None,
help="password for use with authentication and/or sudo"
),
make_option('-P', '--parallel',
dest='parallel',
action='store_true',
default=False,
help="default to parallel execution method"
),
make_option('--port',
default=default_port,
help="SSH connection port"
),
make_option('-r', '--reject-unknown-hosts',
action='store_true',
default=False,
help="reject unknown hosts"
),
make_option('--sudo-password',
default=None,
help="password for use with sudo only",
),
make_option('--system-known-hosts',
default=None,
help="load system known_hosts file before reading user known_hosts"
),
make_option('-R', '--roles',
default=[],
help="comma-separated list of roles to operate on"
),
make_option('-s', '--shell',
default='/bin/bash -l -c',
help="specify a new shell, defaults to '/bin/bash -l -c'"
),
make_option('--show',
metavar='LEVELS',
help="comma-separated list of output levels to show"
),
make_option('--skip-bad-hosts',
action="store_true",
default=False,
help="skip over hosts that can't be reached"
),
make_option('--skip-unknown-tasks',
action="store_true",
default=False,
help="skip over unknown tasks"
),
make_option('--ssh-config-path',
default=default_ssh_config_path,
metavar='PATH',
help="Path to SSH config file"
),
make_option('-t', '--timeout',
type='int',
default=10,
metavar="N",
help="set connection timeout to N seconds"
),
make_option('--banner-timeout',
type='int',
default=15,
metavar="N",
help="set ssh banner timeout to N seconds"
),
make_option('--auth-timeout',
type='int',
default=30,
metavar="N",
help="set timeout for ssh authentication response to N seconds"
),
make_option('-T', '--command-timeout',
dest='command_timeout',
type='int',
default=None,
metavar="N",
help="set remote command timeout to N seconds"
),
make_option('-u', '--user',
default=_get_system_username(),
help="username to use when connecting to remote hosts"
),
make_option('-w', '--warn-only',
action='store_true',
default=False,
help="warn, instead of abort, when commands fail"
),
make_option('-x', '--exclude-hosts',
default=[],
metavar='HOSTS',
help="comma-separated list of hosts to exclude"
),
make_option('-z', '--pool-size',
dest='pool_size',
type='int',
metavar='INT',
default=0,
help="number of concurrent processes to use in parallel mode",
),
]
#
# Environment dictionary - actual dictionary object
#
# Global environment dict. Currently a catchall for everything: config settings
# such as global deep/broad mode, host lists, username etc.
# Most default values are specified in `env_options` above, in the interests of
# preserving DRY: anything in here is generally not settable via the command
# line.
env = _AttributeDict({
'abort_exception': None,
'again_prompt': 'Sorry, try again.',
'all_hosts': [],
'combine_stderr': True,
'colorize_errors': False,
'command': None,
'command_prefixes': [],
'cwd': '', # Must be empty string, not None, for concatenation purposes
'dedupe_hosts': True,
'default_port': default_port,
'eagerly_disconnect': False,
'echo_stdin': True,
'effective_roles': [],
'exclude_hosts': [],
'gateway': None,
'gss_auth': None,
'gss_deleg': None,
'gss_kex': None,
'host': None,
'host_string': None,
'lcwd': '', # Must be empty string, not None, for concatenation purposes
'local_user': _get_system_username(),
'output_prefix': True,
'passwords': {},
'path': '',
'path_behavior': 'append',
'port': default_port,
'real_fabfile': None,
'remote_interrupt': None,
'roles': [],
'roledefs': {},
'shell_env': {},
'skip_bad_hosts': False,
'skip_unknown_tasks': False,
'ssh_config_path': default_ssh_config_path,
'sudo_passwords': {},
'ok_ret_codes': [0], # a list of return codes that indicate success
# -S so sudo accepts passwd via stdin, -p with our known-value prompt for
# later detection (thus %s -- gets filled with env.sudo_prompt at runtime)
'sudo_prefix': "sudo -S -p '%(sudo_prompt)s' ",
'sudo_prompt': 'sudo password:',
'sudo_user': None,
'tasks': [],
'prompts': {},
'use_exceptions_for': {'network': False},
'use_shell': True,
'use_ssh_config': False,
'user': None,
'version': get_version('short')
})
# Fill in exceptions settings
exceptions = ['network']
exception_dict = {}
for e in exceptions:
exception_dict[e] = False
env.use_exceptions_for = _AliasDict(exception_dict,
aliases={'everything': exceptions})
# Add in option defaults
for option in env_options:
env[option.dest] = option.default
#
# Command dictionary
#
# Keys are the command/function names, values are the callables themselves.
# This is filled in when main() runs.
commands = {}
#
# Host connection dict/cache
#
connections = HostConnectionCache()
def _open_session():
transport = connections[env.host_string].get_transport()
# Try passing session-open timeout for Paramiko versions which support it
# (1.14.3+)
try:
session = transport.open_session(timeout=env.timeout)
# Revert to old call behavior if we seem to have hit arity error.
# TODO: consider introspecting the exception to avoid masking other
# TypeErrors; but this is highly fragile, especially when taking i18n into
# account.
except TypeError: # Assume arity error
session = transport.open_session()
return session
def default_channel():
"""
Return a channel object based on ``env.host_string``.
"""
try:
chan = _open_session()
except ssh.SSHException as err:
if str(err) == 'SSH session not active':
connections[env.host_string].close()
del connections[env.host_string]
chan = _open_session()
else:
raise
chan.settimeout(0.1)
chan.input_enabled = True
return chan
#
# Output controls
#
# Keys are "levels" or "groups" of output, values are always boolean,
# determining whether output falling into the given group is printed or not
# printed.
#
# By default, everything except 'debug' is printed, as this is what the average
# user, and new users, are most likely to expect.
#
# See docs/usage.rst for details on what these levels mean.
output = _AliasDict({
'status': True,
'aborts': True,
'warnings': True,
'running': True,
'stdout': True,
'stderr': True,
'exceptions': False,
'debug': False,
'user': True
}, aliases={
'everything': ['warnings', 'running', 'user', 'output', 'exceptions'],
'output': ['stdout', 'stderr'],
'commands': ['stdout', 'running']
})
Zerion Mini Shell 1.0