bdisk/bdisk/confparse.py

127 lines
4.8 KiB
Python

import copy
import re
import os
import utils
import validators
import lxml.etree
from urllib.parse import urlparse
etree = lxml.etree
class Conf(object):
def __init__(self, cfg, profile = None):
"""
A configuration object.
Read a configuration file, parse it, and make it available to the rest
of BDisk.
Args:
cfg The configuration. Can be a filesystem path, a string,
bytes, or a stream. If bytes or a bytestream, it must be
in UTF-8 format.
profile (optional) A sub-profile in the configuration. If None
is provided, we'll first look for the first profile
named 'default' (case-insensitive). If one isn't found,
then the first profile found will be used. Can be a
string (in which we'll automatically search for the
given value in the "name" attribute) or a dict for more
fine-grained profile identification, such as:
{'name': 'PROFILE_NAME',
'id': 1,
'uuid': '00000000-0000-0000-0000-000000000000'}
You can provide any combination of these
(e.g. "profile={'id': 2, 'name' = 'some_profile'}").
"""
self.raw = _detect_cfg(cfg)
self.profile = profile
self.xml = None
self.profile = None
# Mad props to https://stackoverflow.com/a/12728199/733214
self.xpath_re = re.compile('(?<=(?<!\{)\{)[^{}]*(?=\}(?!\}))')
self.substitutions = {}
self.xpaths = ['xpath']
try:
self.xml = etree.fromstring(self.raw)
except lxml.etree.XMLSyntaxError:
raise ValueError('The configuration provided does not seem to be '
'valid')
self.xsd = None
#if not self.validate(): # Need to write the XSD
# raise ValueError('The configuration did not pass XSD/schema '
# 'validation')
self.get_profile()
self.max_recurse = int(self.profile.xpath('//meta/'
'max_recurse')[0].text)
def get_xsd(self):
path = os.path.join(os.path.dirname(__file__),
'bdisk.xsd')
with open(path, 'r') as f:
xsd = f.read()
return(xsd)
def validate(self):
self.xsd = etree.XMLSchema(self.get_xsd())
return(self.xsd.validate(self.xml))
def get_profile(self):
"""Get a configuration profile.
Get a configuration profile from the XML object and set that as a
profile object. If a profile is specified, attempt to find it. If not,
follow the default rules as specified in __init__.
"""
if self.profile:
# A profile identifier was provided
if isinstance(self.profile, str):
_profile_name = self.profile
self.profile = {}
for i in _profile_specifiers:
self.profile[i] = None
self.profile['name'] = _profile_name
elif isinstance(self.profile, dict):
for k in _profile_specifiers:
if k not in self.profile.keys():
self.profile[k] = None
else:
raise TypeError('profile must be a string (name of profile), '
'a dictionary, or None')
xpath = ('/bdisk/'
'profile{0}').format(_profile_xpath_gen(self.profile))
self.profile = self.xml.xpath(xpath)
if not self.profile:
raise RuntimeError('Could not find the profile specified in '
'the given configuration')
else:
# We need to find the default.
profiles = []
for p in self.xml.xpath('/bdisk/profile'):
profiles.append(p)
# Look for one named "default" or "DEFAULT" etc.
for idx, value in enumerate([e.attrib['name'].lower() \
for e in profiles]):
if value == 'default':
self.profile = copy.deepcopy(profiles[idx])
break
# We couldn't find a profile with a default name. Try to grab the
# first profile.
if self.profile is None:
# Grab the first profile.
if profiles:
self.profile = profile[0]
else:
# No profiles found.
raise RuntimeError('Could not find any usable '
'configuration profiles')
return()
def parse_profile(self):
pass