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4.3 KiB

Configuration Utility Module
This module contains functions to load and verify very simple configuration
files. Python supports ".ini" files, which suck, so this module is used
Example Configuration File:
include /path/to/
# these values are the same:
name_protected = "Michael Spang"
name_unprotected = Michael Spang
# these values are not the same:
yes_no = " yes"
no_yes = yes
# this value is an integer
# this value is not an integer
# this is a key with no value
# this key contains whitespace
white space = sure, why not
# these two lines are treated as one
long line = first line \\
second line
Resultant Dictionary:
'name_protected': 'Michael Spang',
'name_unprotected:' 'Michael Spang',
'yes_no': ' yes',
'no_yes': 'yes',
'arbirary_number': 2,
'arbitrary_string': '2',
'csclub': None,
'white space': 'sure, why not'
'long line': 'first line \\n second line'
... (data from ...
from curses.ascii import isspace
class ConfigurationException(Exception):
"""Exception class for incomplete and incorrect configurations."""
def read(filename, included=None):
Function to read a configuration file into a dictionary.
filename - the file to read
included - files previously read (internal)
IOError - when the configuration file cannot be read
if not included:
included = []
if filename in included:
return {}
conffile = open(filename)
options = {}
while True:
line = conffile.readline()
if line == '':
# remove comments
if '#' in line:
line = line[:line.find('#')]
# combine lines when the newline is escaped with \
while len(line) > 1 and line[-2] == '\\':
line = line[:-2] + line[-1]
next = conffile.readline()
line += next
if next == '':
line = line.strip()
# process include statements
if line.find("include") == 0 and isspace(line[7]):
filename = line[8:].strip()
options.update(read(filename, included))
# split 'key = value' into key and value and strip results
pair = map(str.strip, line.split('=', 1))
# found key and value
if len(pair) == 2:
key, val = pair
# found quoted string?
if val and val[0] == val[-1] == '"':
val = val[1:-1]
# unquoted, found num?
elif val:
if "." in val:
val = float(val)
elif val[0] == '0':
val = int(val, 8)
val = int(val)
except ValueError:
# save key and value
options[key] = val
# found only key, value = None
elif len(pair[0]) > 1:
key = pair[0]
options[key] = None
return options
def check_string_fields(filename, field_list, cfg):
"""Function to verify thatfields are strings."""
for field in field_list:
if field not in cfg or type(cfg[field]) is not str:
raise ConfigurationException('expected string value for option "%s" in "%s"' % (field, filename))
def check_integer_fields(filename, field_list, cfg):
"""Function to verify that fields are integers."""
for field in field_list:
if field not in cfg or type(cfg[field]) not in (int, long):
raise ConfigurationException('expected numeric value for option "%s" in "%s"' % (field, filename))
def check_float_fields(filename, field_list, cfg):
"""Function to verify that fields are integers or floats."""
for field in field_list:
if field not in cfg or type(cfg[field]) not in (float, long, int):
raise ConfigurationException('expected float value for option "%s" in "%s"' % (field, filename))