lorax/src/pylorax/template.py
Martin Gracik 272ec190c7 New version
I fixed a lot of bugs with copying files to the initrd, and getting the symlinks.
Also I moved some of the code around, to get a clearer flow.
2009-09-23 12:21:33 +02:00

114 lines
3.5 KiB
Python

#
# template.py
# initrd template class
#
# Copyright (C) 2009 Red Hat, Inc.
#
# 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, see <http://www.gnu.org/licenses/>.
#
# Red Hat Author(s): Martin Gracik <mgracik@redhat.com>
#
import sys
import os
import re
class TemplateError(Exception):
pass
class Template(object):
def __init__(self):
self._actions = []
self.lines = []
self.included_files = []
def preparse(self, filename):
try:
f = open(filename, 'r')
except IOError as why:
sys.stderr.write("ERROR: Unable to open template file '%s': %s\n" % (filename, why))
return False
else:
lines = f.readlines()
f.close()
self.included_files.append(filename)
for line in lines:
line = line.strip()
if line.startswith('#include'):
file_to_include = line.split()[1]
path = os.path.join(os.path.dirname(filename), file_to_include)
if path not in self.included_files:
self.preparse(path)
else:
self.lines.append(line)
def parse(self, supported_actions, variables):
lines = self.lines
# append next line if line ends with '\'
temp = []
for line in lines:
line = line.strip()
if line.endswith('\\'):
line = line[:-1]
line = line.rstrip()
line = line + ' '
else:
line = line + '\n'
temp.append(line)
temp = ''.join(temp)
lines = temp.splitlines()
# check template variables
for lineno, line in enumerate(lines, start=1):
for var in filter(lambda var: var not in variables, re.findall(r'@(.*?)@', line)):
raise TemplateError, "unknown variable '%s' on line %d" % (var, lineno)
# parse the template
for lineno, line in enumerate(lines, start=1):
line, sep, comment = line.partition('#')
if not line:
continue
# expand variables
for var, value in variables.items():
line = re.sub(r'@%s@' % var, value, line)
# get the command
command, line = line.split(None, 1)
if command not in supported_actions:
raise TemplateError, "unknown command '%s' on line %d" % (command, lineno)
# create the action object
regex = supported_actions[command].REGEX
m = re.match(regex, line)
if m:
new_action = supported_actions[command](**m.groupdict())
self._actions.append(new_action)
else:
# didn't match the regex
raise TemplateError, "invalid command format '%s' on line %d" % (line, lineno)
return True
@property
def actions(self):
return self._actions