ansible/lib/ansible/utils/template.py
Jack Neely 2fda9bc743 template.py: Handle purposely raised exceptions in lookup()
If a lookup plugin is run by the lookup() template method it should pass
along any AnsibleError (or child exception classes) rather than just eat
them.  These exceptions are purposely raised by the plugin.
2014-05-30 16:41:20 -04:00

362 lines
13 KiB
Python

# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
#
# This file is part of Ansible
#
# Ansible 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 3 of the License, or
# (at your option) any later version.
#
# Ansible 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 Ansible. If not, see <http://www.gnu.org/licenses/>.
import os
import re
import codecs
import jinja2
from jinja2.runtime import StrictUndefined
from jinja2.exceptions import TemplateSyntaxError
import yaml
import json
from ansible import errors
import ansible.constants as C
import time
import subprocess
import datetime
import pwd
import ast
import traceback
from ansible.utils.string_functions import count_newlines_from_end
class Globals(object):
FILTERS = None
def __init__(self):
pass
def _get_filters():
''' return filter plugin instances '''
if Globals.FILTERS is not None:
return Globals.FILTERS
from ansible import utils
plugins = [ x for x in utils.plugins.filter_loader.all()]
filters = {}
for fp in plugins:
filters.update(fp.filters())
Globals.FILTERS = filters
return Globals.FILTERS
def _get_extensions():
''' return jinja2 extensions to load '''
'''
if some extensions are set via jinja_extensions in ansible.cfg, we try
to load them with the jinja environment
'''
jinja_exts = []
if C.DEFAULT_JINJA2_EXTENSIONS:
'''
Let's make sure the configuration directive doesn't contain spaces
and split extensions in an array
'''
jinja_exts = C.DEFAULT_JINJA2_EXTENSIONS.replace(" ", "").split(',')
return jinja_exts
class Flags:
LEGACY_TEMPLATE_WARNING = False
# TODO: refactor this file
FILTER_PLUGINS = None
_LISTRE = re.compile(r"(\w+)\[(\d+)\]")
JINJA2_OVERRIDE='#jinja2:'
def lookup(name, *args, **kwargs):
from ansible import utils
instance = utils.plugins.lookup_loader.get(name.lower(), basedir=kwargs.get('basedir',None))
vars = kwargs.get('vars', None)
if instance is not None:
# safely catch run failures per #5059
try:
ran = instance.run(*args, inject=vars, **kwargs)
except errors.AnsibleError:
# Plugin raised this on purpose
raise
except Exception, e:
ran = None
if ran:
ran = ",".join(ran)
return ran
else:
raise errors.AnsibleError("lookup plugin (%s) not found" % name)
def template(basedir, varname, vars, lookup_fatal=True, depth=0, expand_lists=True, convert_bare=False, fail_on_undefined=False, filter_fatal=True):
''' templates a data structure by traversing it and substituting for other data structures '''
from ansible import utils
try:
if convert_bare and isinstance(varname, basestring):
first_part = varname.split(".")[0].split("[")[0]
if first_part in vars and '{{' not in varname and '$' not in varname:
varname = "{{%s}}" % varname
if isinstance(varname, basestring):
if '{{' in varname or '{%' in varname:
varname = template_from_string(basedir, varname, vars, fail_on_undefined)
if (varname.startswith("{") and not varname.startswith("{{")) or varname.startswith("["):
eval_results = utils.safe_eval(varname, locals=vars, include_exceptions=True)
if eval_results[1] is None:
varname = eval_results[0]
return varname
elif isinstance(varname, (list, tuple)):
return [template(basedir, v, vars, lookup_fatal, depth, expand_lists, fail_on_undefined=fail_on_undefined) for v in varname]
elif isinstance(varname, dict):
d = {}
for (k, v) in varname.iteritems():
d[k] = template(basedir, v, vars, lookup_fatal, depth, expand_lists, fail_on_undefined=fail_on_undefined)
return d
else:
return varname
except errors.AnsibleFilterError:
if filter_fatal:
raise
else:
return varname
class _jinja2_vars(object):
'''
Helper class to template all variable content before jinja2 sees it.
This is done by hijacking the variable storage that jinja2 uses, and
overriding __contains__ and __getitem__ to look like a dict. Added bonus
is avoiding duplicating the large hashes that inject tends to be.
To facilitate using builtin jinja2 things like range, globals are handled
here.
extras is a list of locals to also search for variables.
'''
def __init__(self, basedir, vars, globals, fail_on_undefined, *extras):
self.basedir = basedir
self.vars = vars
self.globals = globals
self.fail_on_undefined = fail_on_undefined
self.extras = extras
def __contains__(self, k):
if k in self.vars:
return True
for i in self.extras:
if k in i:
return True
if k in self.globals:
return True
return False
def __getitem__(self, varname):
if varname not in self.vars:
for i in self.extras:
if varname in i:
return i[varname]
if varname in self.globals:
return self.globals[varname]
else:
raise KeyError("undefined variable: %s" % varname)
var = self.vars[varname]
# HostVars is special, return it as-is
if isinstance(var, dict) and type(var) != dict:
return var
else:
return template(self.basedir, var, self.vars, fail_on_undefined=self.fail_on_undefined)
def add_locals(self, locals):
'''
If locals are provided, create a copy of self containing those
locals in addition to what is already in this variable proxy.
'''
if locals is None:
return self
return _jinja2_vars(self.basedir, self.vars, self.globals, self.fail_on_undefined, locals, *self.extras)
class J2Template(jinja2.environment.Template):
'''
This class prevents Jinja2 from running _jinja2_vars through dict()
Without this, {% include %} and similar will create new contexts unlike
the special one created in template_from_file. This ensures they are all
alike, with the exception of potential locals.
'''
def new_context(self, vars=None, shared=False, locals=None):
return jinja2.runtime.Context(self.environment, vars.add_locals(locals), self.name, self.blocks)
def template_from_file(basedir, path, vars, vault_password=None):
''' run a file through the templating engine '''
fail_on_undefined = C.DEFAULT_UNDEFINED_VAR_BEHAVIOR
from ansible import utils
realpath = utils.path_dwim(basedir, path)
loader=jinja2.FileSystemLoader([basedir,os.path.dirname(realpath)])
def my_lookup(*args, **kwargs):
kwargs['vars'] = vars
return lookup(*args, basedir=basedir, **kwargs)
def my_finalize(thing):
return thing if thing is not None else ''
environment = jinja2.Environment(loader=loader, trim_blocks=True, extensions=_get_extensions())
environment.filters.update(_get_filters())
environment.globals['lookup'] = my_lookup
environment.globals['finalize'] = my_finalize
if fail_on_undefined:
environment.undefined = StrictUndefined
try:
data = codecs.open(realpath, encoding="utf8").read()
except UnicodeDecodeError:
raise errors.AnsibleError("unable to process as utf-8: %s" % realpath)
except:
raise errors.AnsibleError("unable to read %s" % realpath)
# Get jinja env overrides from template
if data.startswith(JINJA2_OVERRIDE):
eol = data.find('\n')
line = data[len(JINJA2_OVERRIDE):eol]
data = data[eol+1:]
for pair in line.split(','):
(key,val) = pair.split(':')
setattr(environment,key.strip(),ast.literal_eval(val.strip()))
environment.template_class = J2Template
try:
t = environment.from_string(data)
except TemplateSyntaxError, e:
# Throw an exception which includes a more user friendly error message
values = {'name': realpath, 'lineno': e.lineno, 'error': str(e)}
msg = 'file: %(name)s, line number: %(lineno)s, error: %(error)s' % \
values
error = errors.AnsibleError(msg)
raise error
vars = vars.copy()
try:
template_uid = pwd.getpwuid(os.stat(realpath).st_uid).pw_name
except:
template_uid = os.stat(realpath).st_uid
vars['template_host'] = os.uname()[1]
vars['template_path'] = realpath
vars['template_mtime'] = datetime.datetime.fromtimestamp(os.path.getmtime(realpath))
vars['template_uid'] = template_uid
vars['template_fullpath'] = os.path.abspath(realpath)
vars['template_run_date'] = datetime.datetime.now()
managed_default = C.DEFAULT_MANAGED_STR
managed_str = managed_default.format(
host = vars['template_host'],
uid = vars['template_uid'],
file = vars['template_path']
)
vars['ansible_managed'] = time.strftime(
managed_str,
time.localtime(os.path.getmtime(realpath))
)
# This line performs deep Jinja2 magic that uses the _jinja2_vars object for vars
# Ideally, this could use some API where setting shared=True and the object won't get
# passed through dict(o), but I have not found that yet.
try:
res = jinja2.utils.concat(t.root_render_func(t.new_context(_jinja2_vars(basedir, vars, t.globals, fail_on_undefined), shared=True)))
except jinja2.exceptions.UndefinedError, e:
raise errors.AnsibleUndefinedVariable("One or more undefined variables: %s" % str(e))
# The low level calls above do not preserve the newline
# characters at the end of the input data, so we use the
# calculate the difference in newlines and append them
# to the resulting output for parity
res_newlines = count_newlines_from_end(res)
data_newlines = count_newlines_from_end(data)
if data_newlines > res_newlines:
res += '\n' * (data_newlines - res_newlines)
if isinstance(res, unicode):
# do not try to re-template a unicode string
result = res
else:
result = template(basedir, res, vars)
return result
def template_from_string(basedir, data, vars, fail_on_undefined=False):
''' run a string through the (Jinja2) templating engine '''
try:
if type(data) == str:
data = unicode(data, 'utf-8')
def my_finalize(thing):
return thing if thing is not None else ''
environment = jinja2.Environment(trim_blocks=True, undefined=StrictUndefined, extensions=_get_extensions(), finalize=my_finalize)
environment.filters.update(_get_filters())
environment.template_class = J2Template
if '_original_file' in vars:
basedir = os.path.dirname(vars['_original_file'])
filesdir = os.path.abspath(os.path.join(basedir, '..', 'files'))
if os.path.exists(filesdir):
basedir = filesdir
# 6227
if isinstance(data, unicode):
try:
data = data.decode('utf-8')
except UnicodeEncodeError, e:
pass
try:
t = environment.from_string(data)
except Exception, e:
if 'recursion' in str(e):
raise errors.AnsibleError("recursive loop detected in template string: %s" % data)
else:
return data
def my_lookup(*args, **kwargs):
kwargs['vars'] = vars
return lookup(*args, basedir=basedir, **kwargs)
t.globals['lookup'] = my_lookup
t.globals['finalize'] = my_finalize
jvars =_jinja2_vars(basedir, vars, t.globals, fail_on_undefined)
new_context = t.new_context(jvars, shared=True)
rf = t.root_render_func(new_context)
try:
res = jinja2.utils.concat(rf)
except TypeError, te:
if 'StrictUndefined' in str(te):
raise errors.AnsibleUndefinedVariable(
"Unable to look up a name or access an attribute in template string. " + \
"Make sure your variable name does not contain invalid characters like '-'."
)
else:
raise errors.AnsibleError("an unexpected type error occured. Error was %s" % te)
return res
except (jinja2.exceptions.UndefinedError, errors.AnsibleUndefinedVariable):
if fail_on_undefined:
raise
else:
return data