frappy/secop/lib/__init__.py
tasp f9db90d89b update secop_psi/sea.py
fixes after serveral changes in frappy
2022-04-29 16:30:19 +02:00

362 lines
12 KiB
Python

# -*- coding: utf-8 -*-
# *****************************************************************************
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Module authors:
# Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
#
# *****************************************************************************
"""Define helpers"""
import importlib
import linecache
import socket
import sys
import threading
import traceback
from configparser import ConfigParser
from os import environ, path
class GeneralConfig:
"""generalConfig holds server configuration items
generalConfig.init is to be called before starting the server.
Accessing generalConfig.<key> raises an error, when generalConfig.init is
not yet called, except when a default for <key> is set.
For tests and for imports from client code, a module may access generalConfig
without calling generalConfig.init before. For this, it should call
generalConfig.set_default on import to define defaults for the needed keys.
"""
def __init__(self):
self._config = None
self.defaults = {} #: default values. may be set before or after :meth:`init`
def init(self, configfile=None):
"""init default server configuration
:param configfile: if present, keys and values from the [FRAPPY] section are read
if configfile is not given, it tries to guess the location of the configfile
or determine 'piddir', 'logdir', 'confdir' and 'basedir' from the environment.
"""
cfg = {}
mandatory = 'piddir', 'logdir', 'confdir'
repodir = path.abspath(path.join(path.dirname(__file__), '..', '..'))
# create default paths
if path.splitext(sys.executable)[1] == ".exe" and not path.basename(sys.executable).startswith('python'):
# special MS windows environment
cfg.update(piddir='./', logdir='./log', confdir='./')
elif path.exists(path.join(repodir, '.git')):
# running from git repo
cfg['confdir'] = path.join(repodir, 'cfg')
# take logdir and piddir from <repodir>/cfg/generalConfig.cfg
else:
# running on installed system (typically with systemd)
cfg.update(piddir='/var/run/frappy', logdir='/var/log', confdir='/etc/frappy')
if configfile is None:
configfile = environ.get('FRAPPY_CONFIG_FILE',
path.join(cfg['confdir'], 'generalConfig.cfg'))
configfile = path.expanduser(configfile)
if not path.exists(configfile):
raise FileNotFoundError(configfile)
if configfile and path.exists(configfile):
parser = ConfigParser()
parser.optionxform = str
parser.read([configfile])
# mandatory in a general config file:
cfg['logdir'] = cfg['piddir'] = None
cfg['confdir'] = path.dirname(configfile)
# only the FRAPPY section is relevant, other sections might be used by others
for key, value in parser['FRAPPY'].items():
if value.startswith('./'):
cfg[key] = path.abspath(path.join(repodir, value))
else:
# expand ~ to username, also in path lists separated with ':'
cfg[key] = ':'.join(path.expanduser(v) for v in value.split(':'))
else:
for key in mandatory:
cfg[key] = environ.get('FRAPPY_%s' % key.upper(), cfg[key])
missing_keys = [key for key in mandatory if cfg[key] is None]
if missing_keys:
if path.exists(configfile):
raise KeyError('missing value for %s in %s' % (' and '.join(missing_keys), configfile))
raise FileNotFoundError(configfile)
# this is not customizable
cfg['basedir'] = repodir
self._config = cfg
def __getitem__(self, key):
"""access for keys known to exist
:param key: the key (raises an error when key is not available)
:return: the value
"""
try:
return self._config[key]
except KeyError:
return self.defaults[key]
except TypeError:
if key in self.defaults:
# accept retrieving defaults before init
# e.g. 'lazy_number_validation' in secop.datatypes
return self.defaults[key]
raise TypeError('generalConfig.init() has to be called first') from None
def get(self, key, default=None):
"""access for keys not known to exist"""
try:
return self.__getitem__(key)
except KeyError:
return default
def getint(self, key, default=None):
"""access and convert to int"""
try:
return int(self.__getitem__(key))
except KeyError:
return default
def __getattr__(self, key):
"""goodie: use generalConfig.<key> instead of generalConfig.get('<key>')"""
return self.get(key)
@property
def initialized(self):
return bool(self._config)
def set_default(self, key, value):
"""set a default value, in case not set already"""
if key not in self.defaults:
self.defaults[key] = value
def testinit(self, **kwds):
"""for test purposes"""
self._config = kwds
generalConfig = GeneralConfig()
class lazy_property:
"""A property that calculates its value only once."""
def __init__(self, func):
self._func = func
self.__name__ = func.__name__
self.__doc__ = func.__doc__
def __get__(self, obj, obj_class):
if obj is None:
return self
obj.__dict__[self.__name__] = self._func(obj)
return obj.__dict__[self.__name__]
class attrdict(dict):
"""a normal dict, providing access also via attributes"""
def __getattr__(self, key):
return self[key]
def __setattr__(self, key, value):
self[key] = value
def clamp(_min, value, _max):
"""return the median of 3 values,
i.e. value if min <= value <= max, else min or max depending on which side
value lies outside the [min..max] interval. This works even when min > max!
"""
# return median, i.e. clamp the the value between min and max
return sorted([_min, value, _max])[1]
def get_class(spec):
"""loads a class given by string in dotted notation (as python would do)"""
modname, classname = spec.rsplit('.', 1)
if modname.startswith('secop'):
module = importlib.import_module(modname)
else:
# rarely needed by now....
module = importlib.import_module('secop.' + modname)
try:
return getattr(module, classname)
except AttributeError:
raise AttributeError('no such class') from None
def mkthread(func, *args, **kwds):
t = threading.Thread(
name='%s:%s' % (func.__module__, func.__name__),
target=func,
args=args,
kwargs=kwds)
t.daemon = True
t.start()
return t
def formatExtendedFrame(frame):
ret = []
for key, value in frame.f_locals.items():
try:
valstr = repr(value)[:256]
except Exception:
valstr = '<cannot be displayed>'
ret.append(' %-20s = %s\n' % (key, valstr))
ret.append('\n')
return ret
def formatExtendedTraceback(exc_info=None):
if exc_info is None:
etype, value, tb = sys.exc_info()
else:
etype, value, tb = exc_info
ret = ['Traceback (most recent call last):\n']
while tb is not None:
frame = tb.tb_frame
filename = frame.f_code.co_filename
item = ' File "%s", line %d, in %s\n' % (filename, tb.tb_lineno,
frame.f_code.co_name)
linecache.checkcache(filename)
line = linecache.getline(filename, tb.tb_lineno, frame.f_globals)
if line:
item = item + ' %s\n' % line.strip()
ret.append(item)
if filename not in ('<script>', '<string>'):
ret += formatExtendedFrame(tb.tb_frame)
tb = tb.tb_next
ret += traceback.format_exception_only(etype, value)
return ''.join(ret).rstrip('\n')
def formatExtendedStack(level=1):
f = sys._getframe(level)
ret = ['Stack trace (most recent call last):\n\n']
while f is not None:
lineno = f.f_lineno
co = f.f_code
filename = co.co_filename
name = co.co_name
item = ' File "%s", line %d, in %s\n' % (filename, lineno, name)
linecache.checkcache(filename)
line = linecache.getline(filename, lineno, f.f_globals)
if line:
item = item + ' %s\n' % line.strip()
ret.insert(1, item)
if filename != '<script>':
ret[2:2] = formatExtendedFrame(f)
f = f.f_back
return ''.join(ret).rstrip('\n')
def formatException(cut=0, exc_info=None, verbose=False):
"""Format an exception with traceback, but leave out the first `cut`
number of frames.
"""
if verbose:
return formatExtendedTraceback(exc_info)
if exc_info is None:
typ, val, tb = sys.exc_info()
else:
typ, val, tb = exc_info
res = ['Traceback (most recent call last):\n']
tbres = traceback.format_tb(tb, sys.maxsize)
res += tbres[cut:]
res += traceback.format_exception_only(typ, val)
return ''.join(res)
def parseHostPort(host, defaultport):
"""Parse host[:port] string and tuples
Specify 'host[:port]' or a (host, port) tuple for the mandatory argument.
If the port specification is missing, the value of the defaultport is used.
"""
if isinstance(host, (tuple, list)):
host, port = host
elif ':' in host:
host, port = host.rsplit(':', 1)
port = int(port)
else:
port = defaultport
assert 0 < port < 65536
assert ':' not in host
return host, port
def tcpSocket(host, defaultport, timeout=None):
"""Helper for opening a TCP client socket to a remote server.
Specify 'host[:port]' or a (host, port) tuple for the mandatory argument.
If the port specification is missing, the value of the defaultport is used.
If timeout is set to a number, the timout of the connection is set to this
number, else the socket stays in blocking mode.
"""
host, port = parseHostPort(host, defaultport)
# open socket and set options
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if timeout:
s.settimeout(timeout)
# connect
s.connect((host, int(port)))
return s
# keep a reference to socket to avoid (interpreter) shut-down problems
def closeSocket(sock, socket=socket): # pylint: disable=redefined-outer-name
"""Do our best to close a socket."""
if sock is None:
return
try:
sock.shutdown(socket.SHUT_RDWR)
except socket.error:
pass
try:
sock.close()
except socket.error:
pass
def getfqdn(name=''):
"""Get fully qualified hostname."""
return socket.getfqdn(name)
def formatStatusBits(sword, labels, start=0):
"""Return a list of labels according to bit state in `sword` starting
with bit `start` and the first label in `labels`.
"""
result = []
for i, lbl in enumerate(labels, start):
if sword & (1 << i) and lbl:
result.append(lbl)
return result
class UniqueObject:
def __init__(self, name):
self.name = name
def __repr__(self):
return self.name