"""
This is the Django template system.
How it works:
The Lexer.tokenize() function converts a template string (i.e., a string containing
markup with custom template tags) to tokens, which can be either plain text
(TOKEN_TEXT), variables (TOKEN_VAR) or block statements (TOKEN_BLOCK).
The Parser() class takes a list of tokens in its constructor, and its parse()
method returns a compiled template -- which is, under the hood, a list of
Node objects.
Each Node is responsible for creating some sort of output -- e.g. simple text
(TextNode), variable values in a given context (VariableNode), results of basic
logic (IfNode), results of looping (ForNode), or anything else. The core Node
types are TextNode, VariableNode, IfNode and ForNode, but plugin modules can
define their own custom node types.
Each Node has a render() method, which takes a Context and returns a string of
the rendered node. For example, the render() method of a Variable Node returns
the variable's value as a string. The render() method of an IfNode returns the
rendered output of whatever was inside the loop, recursively.
The Template class is a convenient wrapper that takes care of template
compilation and rendering.
Usage:
The only thing you should ever use directly in this file is the Template class.
Create a compiled template object with a template_string, then call render()
with a context. In the compilation stage, the TemplateSyntaxError exception
will be raised if the template doesn't have proper syntax.
Sample code:
>>> import template
>>> s = '''
...
... {% if test %}
... {{ varvalue }}
... {% endif %}
...
... '''
>>> t = template.Template(s)
(t is now a compiled template, and its render() method can be called multiple
times with multiple contexts)
>>> c = template.Context({'test':True, 'varvalue': 'Hello'})
>>> t.render(c)
'\n\n\n Hello
\n\n\n'
>>> c = template.Context({'test':False, 'varvalue': 'Hello'})
>>> t.render(c)
'\n\n\n\n'
"""
import re
from inspect import getargspec
from django.conf import settings
from django.template.context import Context, RequestContext, ContextPopException
from django.utils.itercompat import is_iterable
from django.utils.functional import curry, Promise
from django.utils.text import smart_split
from django.utils.encoding import smart_unicode, force_unicode
from django.utils.translation import ugettext as _
__all__ = ('Template', 'Context', 'RequestContext', 'compile_string')
TOKEN_TEXT = 0
TOKEN_VAR = 1
TOKEN_BLOCK = 2
TOKEN_COMMENT = 3
# template syntax constants
FILTER_SEPARATOR = '|'
FILTER_ARGUMENT_SEPARATOR = ':'
VARIABLE_ATTRIBUTE_SEPARATOR = '.'
BLOCK_TAG_START = '{%'
BLOCK_TAG_END = '%}'
VARIABLE_TAG_START = '{{'
VARIABLE_TAG_END = '}}'
COMMENT_TAG_START = '{#'
COMMENT_TAG_END = '#}'
SINGLE_BRACE_START = '{'
SINGLE_BRACE_END = '}'
ALLOWED_VARIABLE_CHARS = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_.'
# what to report as the origin for templates that come from non-loader sources
# (e.g. strings)
UNKNOWN_SOURCE="<unknown source>"
# match a variable or block tag and capture the entire tag, including start/end delimiters
tag_re = re.compile('(%s.*?%s|%s.*?%s|%s.*?%s)' % (re.escape(BLOCK_TAG_START), re.escape(BLOCK_TAG_END),
re.escape(VARIABLE_TAG_START), re.escape(VARIABLE_TAG_END),
re.escape(COMMENT_TAG_START), re.escape(COMMENT_TAG_END)))
# matches if the string is valid number
number_re = re.compile(r'[-+]?(\d+|\d*\.\d+)$')
# global dictionary of libraries that have been loaded using get_library
libraries = {}
# global list of libraries to load by default for a new parser
builtins = []
# True if TEMPLATE_STRING_IF_INVALID contains a format string (%s). None means
# uninitialised.
invalid_var_format_string = None
class TemplateSyntaxError(Exception):
def __str__(self):
try:
import cStringIO as StringIO
except ImportError:
import StringIO
output = StringIO.StringIO()
output.write(Exception.__str__(self))
# Check if we wrapped an exception and print that too.
if hasattr(self, 'exc_info'):
import traceback
output.write('\n\nOriginal ')
e = self.exc_info
traceback.print_exception(e[0], e[1], e[2], 500, output)
return output.getvalue()
class TemplateDoesNotExist(Exception):
pass
class TemplateEncodingError(Exception):
pass
class VariableDoesNotExist(Exception):
def __init__(self, msg, params=()):
self.msg = msg
self.params = params
def __str__(self):
return self.msg % self.params
class InvalidTemplateLibrary(Exception):
pass
class Origin(object):
def __init__(self, name):
self.name = name
def reload(self):
raise NotImplementedError
def __str__(self):
return self.name
class StringOrigin(Origin):
def __init__(self, source):
super(StringOrigin, self).__init__(UNKNOWN_SOURCE)
self.source = source
def reload(self):
return self.source
class Template(object):
def __init__(self, template_string, origin=None, name=''):
"Compilation stage"
try:
template_string = smart_unicode(template_string)
except UnicodeDecodeError:
raise TemplateEncodingError("Templates can only be constructed from unicode or UTF-8 strings.")
if settings.TEMPLATE_DEBUG and origin == None:
origin = StringOrigin(template_string)
# Could do some crazy stack-frame stuff to record where this string
# came from...
self.nodelist = compile_string(template_string, origin)
self.name = name
def __iter__(self):
for node in self.nodelist:
for subnode in node:
yield subnode
def render(self, context):
"Display stage -- can be called many times"
return self.nodelist.render(context)
def compile_string(template_string, origin):
"Compiles template_string into NodeList ready for rendering"
lexer = lexer_factory(template_string, origin)
parser = parser_factory(lexer.tokenize())
return parser.parse()
class Token(object):
def __init__(self, token_type, contents):
"The token_type must be TOKEN_TEXT, TOKEN_VAR, TOKEN_BLOCK or TOKEN_COMMENT"
self.token_type, self.contents = token_type, contents
def __str__(self):
return '<%s token: "%s...">' % \
({TOKEN_TEXT: 'Text', TOKEN_VAR: 'Var', TOKEN_BLOCK: 'Block', TOKEN_COMMENT: 'Comment'}[self.token_type],
self.contents[:20].replace('\n', ''))
def split_contents(self):
return list(smart_split(self.contents))
class Lexer(object):
def __init__(self, template_string, origin):
self.template_string = template_string
self.origin = origin
def tokenize(self):
"Return a list of tokens from a given template_string"
in_tag = False
result = []
for bit in tag_re.split(self.template_string):
if bit:
result.append(self.create_token(bit, in_tag))
in_tag = not in_tag
return result
def create_token(self, token_string, in_tag):
"""
Convert the given token string into a new Token object and return it.
If in_tag is True, we are processing something that matched a tag,
otherwise it should be treated as a literal string.
"""
if in_tag:
if token_string.startswith(VARIABLE_TAG_START):
token = Token(TOKEN_VAR, token_string[len(VARIABLE_TAG_START):-len(VARIABLE_TAG_END)].strip())
elif token_string.startswith(BLOCK_TAG_START):
token = Token(TOKEN_BLOCK, token_string[len(BLOCK_TAG_START):-len(BLOCK_TAG_END)].strip())
elif token_string.startswith(COMMENT_TAG_START):
token = Token(TOKEN_COMMENT, '')
else:
token = Token(TOKEN_TEXT, token_string)
return token
class DebugLexer(Lexer):
def __init__(self, template_string, origin):
super(DebugLexer, self).__init__(template_string, origin)
def tokenize(self):
"Return a list of tokens from a given template_string"
result, upto = [], 0
for match in tag_re.finditer(self.template_string):
start, end = match.span()
if start > upto:
result.append(self.create_token(self.template_string[upto:start], (upto, start), False))
upto = start
result.append(self.create_token(self.template_string[start:end], (start, end), True))
upto = end
last_bit = self.template_string[upto:]
if last_bit:
result.append(self.create_token(last_bit, (upto, upto + len(last_bit)), False))
return result
def create_token(self, token_string, source, in_tag):
token = super(DebugLexer, self).create_token(token_string, in_tag)
token.source = self.origin, source
return token
class Parser(object):
def __init__(self, tokens):
self.tokens = tokens
self.tags = {}
self.filters = {}
for lib in builtins:
self.add_library(lib)
def parse(self, parse_until=None):
if parse_until is None: parse_until = []
nodelist = self.create_nodelist()
while self.tokens:
token = self.next_token()
if token.token_type == TOKEN_TEXT:
self.extend_nodelist(nodelist, TextNode(token.contents), token)
elif token.token_type == TOKEN_VAR:
if not token.contents:
self.empty_variable(token)
filter_expression = self.compile_filter(token.contents)
var_node = self.create_variable_node(filter_expression)
self.extend_nodelist(nodelist, var_node,token)
elif token.token_type == TOKEN_BLOCK:
if token.contents in parse_until:
# put token back on token list so calling code knows why it terminated
self.prepend_token(token)
return nodelist
try:
command = token.contents.split()[0]
except IndexError:
self.empty_block_tag(token)
# execute callback function for this tag and append resulting node
self.enter_command(command, token)
try:
compile_func = self.tags[command]
except KeyError:
self.invalid_block_tag(token, command)
try:
compiled_result = compile_func(self, token)
except TemplateSyntaxError, e:
if not self.compile_function_error(token, e):
raise
self.extend_nodelist(nodelist, compiled_result, token)
self.exit_command()
if parse_until:
self.unclosed_block_tag(parse_until)
return nodelist
def skip_past(self, endtag):
while self.tokens:
token = self.next_token()
if token.token_type == TOKEN_BLOCK and token.contents == endtag:
return
self.unclosed_block_tag([endtag])
def create_variable_node(self, filter_expression):
return VariableNode(filter_expression)
def create_nodelist(self):
return NodeList()
def extend_nodelist(self, nodelist, node, token):
nodelist.append(node)
def enter_command(self, command, token):
pass
def exit_command(self):
pass
def error(self, token, msg ):
return TemplateSyntaxError(msg)
def empty_variable(self, token):
raise self.error( token, "Empty variable tag")
def empty_block_tag(self, token):
raise self.error( token, "Empty block tag")
def invalid_block_tag(self, token, command):
raise self.error( token, "Invalid block tag: '%s'" % command)
def unclosed_block_tag(self, parse_until):
raise self.error(None, "Unclosed tags: %s " % ', '.join(parse_until))
def compile_function_error(self, token, e):
pass
def next_token(self):
return self.tokens.pop(0)
def prepend_token(self, token):
self.tokens.insert(0, token)
def delete_first_token(self):
del self.tokens[0]
def add_library(self, lib):
self.tags.update(lib.tags)
self.filters.update(lib.filters)
def compile_filter(self, token):
"Convenient wrapper for FilterExpression"
return FilterExpression(token, self)
def find_filter(self, filter_name):
if filter_name in self.filters:
return self.filters[filter_name]
else:
raise TemplateSyntaxError, "Invalid filter: '%s'" % filter_name
class DebugParser(Parser):
def __init__(self, lexer):
super(DebugParser, self).__init__(lexer)
self.command_stack = []
def enter_command(self, command, token):
self.command_stack.append( (command, token.source) )
def exit_command(self):
self.command_stack.pop()
def error(self, token, msg):
return self.source_error(token.source, msg)
def source_error(self, source,msg):
e = TemplateSyntaxError(msg)
e.source = source
return e
def create_nodelist(self):
return DebugNodeList()
def create_variable_node(self, contents):
return DebugVariableNode(contents)
def extend_nodelist(self, nodelist, node, token):
node.source = token.source
super(DebugParser, self).extend_nodelist(nodelist, node, token)
def unclosed_block_tag(self, parse_until):
command, source = self.command_stack.pop()
msg = "Unclosed tag '%s'. Looking for one of: %s " % (command, ', '.join(parse_until))
raise self.source_error( source, msg)
def compile_function_error(self, token, e):
if not hasattr(e, 'source'):
e.source = token.source
def lexer_factory(*args, **kwargs):
if settings.TEMPLATE_DEBUG:
return DebugLexer(*args, **kwargs)
else:
return Lexer(*args, **kwargs)
def parser_factory(*args, **kwargs):
if settings.TEMPLATE_DEBUG:
return DebugParser(*args, **kwargs)
else:
return Parser(*args, **kwargs)
class TokenParser(object):
"""
Subclass this and implement the top() method to parse a template line. When
instantiating the parser, pass in the line from the Django template parser.
The parser's "tagname" instance-variable stores the name of the tag that
the filter was called with.
"""
def __init__(self, subject):
self.subject = subject
self.pointer = 0
self.backout = []
self.tagname = self.tag()
def top(self):
"Overload this method to do the actual parsing and return the result."
raise NotImplemented
def more(self):
"Returns True if there is more stuff in the tag."
return self.pointer < len(self.subject)
def back(self):
"Undoes the last microparser. Use this for lookahead and backtracking."
if not len(self.backout):
raise TemplateSyntaxError, "back called without some previous parsing"
self.pointer = self.backout.pop()
def tag(self):
"A microparser that just returns the next tag from the line."
subject = self.subject
i = self.pointer
if i >= len(subject):
raise TemplateSyntaxError, "expected another tag, found end of string: %s" % subject
p = i
while i < len(subject) and subject[i] not in (' ', '\t'):
i += 1
s = subject[p:i]
while i < len(subject) and subject[i] in (' ', '\t'):
i += 1
self.backout.append(self.pointer)
self.pointer = i
return s
def value(self):
"A microparser that parses for a value: some string constant or variable name."
subject = self.subject
i = self.pointer
if i >= len(subject):
raise TemplateSyntaxError, "Searching for value. Expected another value but found end of string: %s" % subject
if subject[i] in ('"', "'"):
p = i
i += 1
while i < len(subject) and subject[i] != subject[p]:
i += 1
if i >= len(subject):
raise TemplateSyntaxError, "Searching for value. Unexpected end of string in column %d: %s" % (i, subject)
i += 1
res = subject[p:i]
while i < len(subject) and subject[i] in (' ', '\t'):
i += 1
self.backout.append(self.pointer)
self.pointer = i
return res
else:
p = i
while i < len(subject) and subject[i] not in (' ', '\t'):
if subject[i] in ('"', "'"):
c = subject[i]
i += 1
while i < len(subject) and subject[i] != c:
i += 1
if i >= len(subject):
raise TemplateSyntaxError, "Searching for value. Unexpected end of string in column %d: %s" % (i, subject)
i += 1
s = subject[p:i]
while i < len(subject) and subject[i] in (' ', '\t'):
i += 1
self.backout.append(self.pointer)
self.pointer = i
return s
filter_raw_string = r"""
^%(i18n_open)s"(?P%(str)s)"%(i18n_close)s|
^"(?P%(str)s)"|
^(?P[%(var_chars)s]+)|
(?:%(filter_sep)s
(?P\w+)
(?:%(arg_sep)s
(?:
%(i18n_open)s"(?P%(str)s)"%(i18n_close)s|
"(?P%(str)s)"|
(?P[%(var_chars)s]+)
)
)?
)""" % {
'str': r"""[^"\\]*(?:\\.[^"\\]*)*""",
'var_chars': "\w\." ,
'filter_sep': re.escape(FILTER_SEPARATOR),
'arg_sep': re.escape(FILTER_ARGUMENT_SEPARATOR),
'i18n_open' : re.escape("_("),
'i18n_close' : re.escape(")"),
}
filter_raw_string = filter_raw_string.replace("\n", "").replace(" ", "")
filter_re = re.compile(filter_raw_string, re.UNICODE)
class FilterExpression(object):
"""
Parses a variable token and its optional filters (all as a single string),
and return a list of tuples of the filter name and arguments.
Sample:
>>> token = 'variable|default:"Default value"|date:"Y-m-d"'
>>> p = FilterParser(token)
>>> p.filters
[('default', 'Default value'), ('date', 'Y-m-d')]
>>> p.var
'variable'
This class should never be instantiated outside of the
get_filters_from_token helper function.
"""
def __init__(self, token, parser):
self.token = token
matches = filter_re.finditer(token)
var = None
filters = []
upto = 0
for match in matches:
start = match.start()
if upto != start:
raise TemplateSyntaxError, "Could not parse some characters: %s|%s|%s" % \
(token[:upto], token[upto:start], token[start:])
if var == None:
var, constant, i18n_constant = match.group("var", "constant", "i18n_constant")
if i18n_constant:
var = '"%s"' % _(i18n_constant)
elif constant:
var = '"%s"' % constant
upto = match.end()
if var == None:
raise TemplateSyntaxError, "Could not find variable at start of %s" % token
elif var.find(VARIABLE_ATTRIBUTE_SEPARATOR + '_') > -1 or var[0] == '_':
raise TemplateSyntaxError, "Variables and attributes may not begin with underscores: '%s'" % var
else:
filter_name = match.group("filter_name")
args = []
constant_arg, i18n_arg, var_arg = match.group("constant_arg", "i18n_arg", "var_arg")
if i18n_arg:
args.append((False, _(i18n_arg.replace(r'\"', '"'))))
elif constant_arg is not None:
args.append((False, constant_arg.replace(r'\"', '"')))
elif var_arg:
args.append((True, var_arg))
filter_func = parser.find_filter(filter_name)
self.args_check(filter_name,filter_func, args)
filters.append( (filter_func,args))
upto = match.end()
if upto != len(token):
raise TemplateSyntaxError, "Could not parse the remainder: '%s' from '%s'" % (token[upto:], token)
self.var, self.filters = var, filters
def resolve(self, context, ignore_failures=False):
try:
obj = resolve_variable(self.var, context)
except VariableDoesNotExist:
if ignore_failures:
obj = None
else:
if settings.TEMPLATE_STRING_IF_INVALID:
global invalid_var_format_string
if invalid_var_format_string is None:
invalid_var_format_string = '%s' in settings.TEMPLATE_STRING_IF_INVALID
if invalid_var_format_string:
return settings.TEMPLATE_STRING_IF_INVALID % self.var
return settings.TEMPLATE_STRING_IF_INVALID
else:
obj = settings.TEMPLATE_STRING_IF_INVALID
for func, args in self.filters:
arg_vals = []
for lookup, arg in args:
if not lookup:
arg_vals.append(arg)
else:
arg_vals.append(resolve_variable(arg, context))
obj = func(obj, *arg_vals)
return obj
def args_check(name, func, provided):
provided = list(provided)
plen = len(provided)
# Check to see if a decorator is providing the real function.
func = getattr(func, '_decorated_function', func)
args, varargs, varkw, defaults = getargspec(func)
# First argument is filter input.
args.pop(0)
if defaults:
nondefs = args[:-len(defaults)]
else:
nondefs = args
# Args without defaults must be provided.
try:
for arg in nondefs:
provided.pop(0)
except IndexError:
# Not enough
raise TemplateSyntaxError, "%s requires %d arguments, %d provided" % (name, len(nondefs), plen)
# Defaults can be overridden.
defaults = defaults and list(defaults) or []
try:
for parg in provided:
defaults.pop(0)
except IndexError:
# Too many.
raise TemplateSyntaxError, "%s requires %d arguments, %d provided" % (name, len(nondefs), plen)
return True
args_check = staticmethod(args_check)
def __str__(self):
return self.token
def resolve_variable(path, context):
"""
Returns the resolved variable, which may contain attribute syntax, within
the given context. The variable may be a hard-coded string (if it begins
and ends with single or double quote marks).
>>> c = {'article': {'section':'News'}}
>>> resolve_variable('article.section', c)
'News'
>>> resolve_variable('article', c)
{'section': 'News'}
>>> class AClass: pass
>>> c = AClass()
>>> c.article = AClass()
>>> c.article.section = 'News'
>>> resolve_variable('article.section', c)
'News'
(The example assumes VARIABLE_ATTRIBUTE_SEPARATOR is '.')
"""
if number_re.match(path):
number_type = '.' in path and float or int
current = number_type(path)
elif path[0] in ('"', "'") and path[0] == path[-1]:
current = path[1:-1]
else:
current = context
bits = path.split(VARIABLE_ATTRIBUTE_SEPARATOR)
while bits:
try: # dictionary lookup
current = current[bits[0]]
except (TypeError, AttributeError, KeyError):
try: # attribute lookup
current = getattr(current, bits[0])
if callable(current):
if getattr(current, 'alters_data', False):
current = settings.TEMPLATE_STRING_IF_INVALID
else:
try: # method call (assuming no args required)
current = current()
except TypeError: # arguments *were* required
# GOTCHA: This will also catch any TypeError
# raised in the function itself.
current = settings.TEMPLATE_STRING_IF_INVALID # invalid method call
except Exception, e:
if getattr(e, 'silent_variable_failure', False):
current = settings.TEMPLATE_STRING_IF_INVALID
else:
raise
except (TypeError, AttributeError):
try: # list-index lookup
current = current[int(bits[0])]
except (IndexError, # list index out of range
ValueError, # invalid literal for int()
KeyError, # current is a dict without `int(bits[0])` key
TypeError, # unsubscriptable object
):
raise VariableDoesNotExist("Failed lookup for key [%s] in %r", (bits[0], current)) # missing attribute
except Exception, e:
if getattr(e, 'silent_variable_failure', False):
current = settings.TEMPLATE_STRING_IF_INVALID
else:
raise
del bits[0]
if isinstance(current, (basestring, Promise)):
try:
current = force_unicode(current)
except UnicodeDecodeError:
# Failing to convert to unicode can happen sometimes (e.g. debug
# tracebacks). So we allow it in this particular instance.
pass
return current
class Node(object):
def render(self, context):
"Return the node rendered as a string"
pass
def __iter__(self):
yield self
def get_nodes_by_type(self, nodetype):
"Return a list of all nodes (within this node and its nodelist) of the given type"
nodes = []
if isinstance(self, nodetype):
nodes.append(self)
if hasattr(self, 'nodelist'):
nodes.extend(self.nodelist.get_nodes_by_type(nodetype))
return nodes
class NodeList(list):
def render(self, context):
bits = []
for node in self:
if isinstance(node, Node):
bits.append(self.render_node(node, context))
else:
bits.append(node)
return ''.join([force_unicode(b) for b in bits])
def get_nodes_by_type(self, nodetype):
"Return a list of all nodes of the given type"
nodes = []
for node in self:
nodes.extend(node.get_nodes_by_type(nodetype))
return nodes
def render_node(self, node, context):
return node.render(context)
class DebugNodeList(NodeList):
def render_node(self, node, context):
try:
result = node.render(context)
except TemplateSyntaxError, e:
if not hasattr(e, 'source'):
e.source = node.source
raise
except Exception, e:
from sys import exc_info
wrapped = TemplateSyntaxError('Caught an exception while rendering: %s' % e)
wrapped.source = node.source
wrapped.exc_info = exc_info()
raise wrapped
return result
class TextNode(Node):
def __init__(self, s):
self.s = s
def __repr__(self):
return "" % self.s[:25]
def render(self, context):
return self.s
class VariableNode(Node):
def __init__(self, filter_expression):
self.filter_expression = filter_expression
def __repr__(self):
return "" % self.filter_expression
def render(self, context):
return self.filter_expression.resolve(context)
class DebugVariableNode(VariableNode):
def render(self, context):
try:
return self.filter_expression.resolve(context)
except TemplateSyntaxError, e:
if not hasattr(e, 'source'):
e.source = self.source
raise
def generic_tag_compiler(params, defaults, name, node_class, parser, token):
"Returns a template.Node subclass."
bits = token.split_contents()[1:]
bmax = len(params)
def_len = defaults and len(defaults) or 0
bmin = bmax - def_len
if(len(bits) < bmin or len(bits) > bmax):
if bmin == bmax:
message = "%s takes %s arguments" % (name, bmin)
else:
message = "%s takes between %s and %s arguments" % (name, bmin, bmax)
raise TemplateSyntaxError, message
return node_class(bits)
class Library(object):
def __init__(self):
self.filters = {}
self.tags = {}
def tag(self, name=None, compile_function=None):
if name == None and compile_function == None:
# @register.tag()
return self.tag_function
elif name != None and compile_function == None:
if(callable(name)):
# @register.tag
return self.tag_function(name)
else:
# @register.tag('somename') or @register.tag(name='somename')
def dec(func):
return self.tag(name, func)
return dec
elif name != None and compile_function != None:
# register.tag('somename', somefunc)
self.tags[name] = compile_function
return compile_function
else:
raise InvalidTemplateLibrary, "Unsupported arguments to Library.tag: (%r, %r)", (name, compile_function)
def tag_function(self,func):
self.tags[getattr(func, "_decorated_function", func).__name__] = func
return func
def filter(self, name=None, filter_func=None):
if name == None and filter_func == None:
# @register.filter()
return self.filter_function
elif filter_func == None:
if(callable(name)):
# @register.filter
return self.filter_function(name)
else:
# @register.filter('somename') or @register.filter(name='somename')
def dec(func):
return self.filter(name, func)
return dec
elif name != None and filter_func != None:
# register.filter('somename', somefunc)
self.filters[name] = filter_func
return filter_func
else:
raise InvalidTemplateLibrary, "Unsupported arguments to Library.filter: (%r, %r)", (name, filter_func)
def filter_function(self, func):
self.filters[getattr(func, "_decorated_function", func).__name__] = func
return func
def simple_tag(self,func):
params, xx, xxx, defaults = getargspec(func)
class SimpleNode(Node):
def __init__(self, vars_to_resolve):
self.vars_to_resolve = vars_to_resolve
def render(self, context):
resolved_vars = [resolve_variable(var, context) for var in self.vars_to_resolve]
return func(*resolved_vars)
compile_func = curry(generic_tag_compiler, params, defaults, getattr(func, "_decorated_function", func).__name__, SimpleNode)
compile_func.__doc__ = func.__doc__
self.tag(getattr(func, "_decorated_function", func).__name__, compile_func)
return func
def inclusion_tag(self, file_name, context_class=Context, takes_context=False):
def dec(func):
params, xx, xxx, defaults = getargspec(func)
if takes_context:
if params[0] == 'context':
params = params[1:]
else:
raise TemplateSyntaxError, "Any tag function decorated with takes_context=True must have a first argument of 'context'"
class InclusionNode(Node):
def __init__(self, vars_to_resolve):
self.vars_to_resolve = vars_to_resolve
def render(self, context):
resolved_vars = [resolve_variable(var, context) for var in self.vars_to_resolve]
if takes_context:
args = [context] + resolved_vars
else:
args = resolved_vars
dict = func(*args)
if not getattr(self, 'nodelist', False):
from django.template.loader import get_template, select_template
if not isinstance(file_name, basestring) and is_iterable(file_name):
t = select_template(file_name)
else:
t = get_template(file_name)
self.nodelist = t.nodelist
return self.nodelist.render(context_class(dict))
compile_func = curry(generic_tag_compiler, params, defaults, getattr(func, "_decorated_function", func).__name__, InclusionNode)
compile_func.__doc__ = func.__doc__
self.tag(getattr(func, "_decorated_function", func).__name__, compile_func)
return func
return dec
def get_library(module_name):
lib = libraries.get(module_name, None)
if not lib:
try:
mod = __import__(module_name, {}, {}, [''])
except ImportError, e:
raise InvalidTemplateLibrary, "Could not load template library from %s, %s" % (module_name, e)
try:
lib = mod.register
libraries[module_name] = lib
except AttributeError:
raise InvalidTemplateLibrary, "Template library %s does not have a variable named 'register'" % module_name
return lib
def add_to_builtins(module_name):
builtins.append(get_library(module_name))
add_to_builtins('django.template.defaulttags')
add_to_builtins('django.template.defaultfilters')