/usr/lib/python2.7/dist-packages/cobbler/template_api.py is in python-cobbler 2.4.1-0ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 | """
Cobbler provides builtin methods for use in Cheetah templates. $SNIPPET is one
such function and is now used to implement Cobbler's SNIPPET:: syntax.
Written by Daniel Guernsey <danpg102@gmail.com>
Contributions by Michael DeHaan <michael.dehaan AT gmail>
US Government work; No explicit copyright attached to this file.
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., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
"""
import Cheetah.Template
import os.path
import re
import utils
from cexceptions import *
CHEETAH_MACROS_FILE = '/etc/cobbler/cheetah_macros'
# This class is defined using the Cheetah language. Using the 'compile' function
# we can compile the source directly into a python class. This class will allow
# us to define the cheetah builtins.
BuiltinTemplate = Cheetah.Template.Template.compile(source="\n".join([
# This part (see 'Template' below
# for the other part) handles the actual inclusion of the file contents. We
# still need to make the snippet's namespace (searchList) available to the
# template calling SNIPPET (done in the other part).
# Moved the other functions into /etc/cobbler/cheetah_macros
# Left SNIPPET here since it is very important.
# This function can be used in two ways:
# Cheetah syntax:
#
# $SNIPPET('my_snippet')
#
# SNIPPET syntax:
#
# SNIPPET::my_snippet
#
# This follows all of the rules of snippets and advanced snippets. First it
# searches for a per-system snippet, then a per-profile snippet, then a
# general snippet. If none is found, a comment explaining the error is
# substituted.
"#def SNIPPET($file)",
"#set $snippet = $read_snippet($file)",
"#if $snippet",
"#include source=$snippet",
"#else",
"# Error: no snippet data for $file",
"#end if",
"#end def",
]) + "\n")
MacrosTemplate = Cheetah.Template.Template.compile(file=CHEETAH_MACROS_FILE)
class Template(BuiltinTemplate, MacrosTemplate):
"""
This class will allow us to include any pure python builtin functions.
It derives from the cheetah-compiled class above. This way, we can include
both types (cheetah and pure python) of builtins in the same base template.
We don't need to override __init__
"""
# OK, so this function gets called by Cheetah.Template.Template.__init__ to
# compile the template into a class. This is probably a kludge, but it
# add a baseclass argument to the standard compile (see Cheetah's compile
# docstring) and returns the resulting class. This argument, of course,
# points to this class. Now any methods entered here (or in the base class
# above) will be accessible to all cheetah templates compiled by cobbler.
def compile(klass, *args, **kwargs):
"""
Compile a cheetah template with cobbler modifications. Modifications
include SNIPPET:: syntax replacement and inclusion of cobbler builtin
methods.
"""
def replacer(match):
return "$SNIPPET('%s')" % match.group(1)
def preprocess(source, file):
# Normally, the cheetah compiler worries about this, but we need to
# preprocess the actual source
if source is None:
if isinstance(file, basestring):
if os.path.exists(file):
f = open(file)
source = "#errorCatcher Echo\n" + f.read()
f.close()
else:
source = "# Unable to read %s\n" % file
elif hasattr(file, 'read'):
source = file.read()
file = None # Stop Cheetah from throwing a fit.
rx = re.compile(r'SNIPPET::([A-Za-z0-9_\-\/\.]+)')
results = rx.sub(replacer, source)
return (results, file)
preprocessors = [preprocess]
if kwargs.has_key('preprocessors'):
preprocessors.extend(kwargs['preprocessors'])
kwargs['preprocessors'] = preprocessors
# Instruct Cheetah to use this class as the base for all cheetah templates
if not kwargs.has_key('baseclass'):
kwargs['baseclass'] = Template
# Now let Cheetah do the actual compilation
return Cheetah.Template.Template.compile(*args, **kwargs)
compile = classmethod(compile)
def read_snippet(self, file):
"""
Locate the appropriate snippet for the current system and profile and
read it's contents.
This file could be located in a remote location.
This will first check for a per-system snippet, a per-profile snippet,
a distro snippet, and a general snippet. If no snippet is located, it
returns None.
"""
for snipclass in ('system', 'profile', 'distro'):
if self.varExists('%s_name' % snipclass):
fullpath = '%s/per_%s/%s/%s' % (self.getVar('snippetsdir'),
snipclass, file, self.getVar('%s_name' % snipclass))
try:
contents = utils.read_file_contents(fullpath, fetch_if_remote=True)
return contents
except FileNotFoundException:
pass
try:
return "#errorCatcher ListErrors\n" + utils.read_file_contents('%s/%s' % (self.getVar('snippetsdir'), file), fetch_if_remote=True)
except FileNotFoundException:
return None
def SNIPPET(self, file):
"""
Include the contents of the named snippet here. This is equivalent to
the #include directive in Cheetah, except that it searches for system
and profile specific snippets, and it includes the snippet's namespace.
This may be a little frobby, but it's really cool. This is a pure python
portion of SNIPPET that appends the snippet's searchList to the caller's
searchList. This makes any #defs within a given snippet available to the
template that included the snippet.
"""
# First, do the actual inclusion. Cheetah (when processing #include)
# will track the inclusion in self._CHEETAH__cheetahIncludes
result = BuiltinTemplate.SNIPPET(self, file)
# Now do our dirty work: locate the new include, and append its
# searchList to ours.
# We have to compute the full path again? Eww.
# This weird method is getting even weirder, the cheetah includes keys
# are no longer filenames but actual contents of snippets. Regardless
# this seems to work and hopefully it will be ok.
snippet_contents = self.read_snippet(file);
if snippet_contents:
# Only include what we don't already have. Because Cheetah
# passes our searchList into included templates, the snippet's
# searchList will include this templates searchList. We need to
# avoid duplicating entries.
childList = self._CHEETAH__cheetahIncludes[snippet_contents].searchList()
myList = self.searchList()
for childElem in childList:
if not childElem in myList:
myList.append(childElem)
return result
# This function is used by several cheetah methods in cheetah_macros.
# It can be used by the end user as well.
# Ex: Replace all instances of '/etc/banner' with a value stored in
# $new_banner
#
# sed 's/$sedesc("/etc/banner")/$sedesc($new_banner)/'
#
def sedesc(self, value):
"""
Escape a string for use in sed.
"""
def escchar(c):
if c in '/^.[]$()|*+?{}\\':
return '\\' + c
else:
return c
return ''.join([escchar(c) for c in value])
|