Source code for mezzanine.template

from __future__ import unicode_literals

from functools import wraps
import warnings

from django import template
from django import VERSION as DJANGO_VERSION

[docs]class Library(template.Library): """ Extends ``django.template.Library`` providing several shortcuts that attempt to take the leg-work out of creating different types of template tags. """
[docs] def as_tag(self, tag_func): """ Creates a tag expecting the format: ``{% tag_name as var_name %}`` The decorated func returns the value that is given to ``var_name`` in the template. """ package = tag_func.__module__.split(".")[0] if DJANGO_VERSION >= (1, 9) and package != "mezzanine": warnings.warn( "The `as_tag` template tag builder is deprecated in favour of " "Django's built-in `simple_tag`, which supports variable " "assignment in Django 1.9 and above.", DeprecationWarning, stacklevel=2 ) @wraps(tag_func) def tag_wrapper(parser, token): class AsTagNode(template.Node): def render(self, context): parts = token.split_contents() # Resolve variables if their names are given. def resolve(arg): try: return template.Variable(arg).resolve(context) except template.VariableDoesNotExist: return arg args, kwargs = [], {} for arg in parts[1:-2]: if "=" in arg: name, val = arg.split("=", 1) if name in tag_func.__code__.co_varnames: kwargs[name] = resolve(val) continue args.append(resolve(arg)) context[parts[-1]] = tag_func(*args, **kwargs) return "" return AsTagNode() return self.tag(tag_wrapper)
[docs] def render_tag(self, tag_func): """ Creates a tag using the decorated func as the render function for the template tag node. The render function takes two arguments - the template context and the tag token. """ @wraps(tag_func) def tag_wrapper(parser, token): class RenderTagNode(template.Node): def render(self, context): return tag_func(context, token) return RenderTagNode() return self.tag(tag_wrapper)
[docs] def to_end_tag(self, tag_func): """ Creates a tag that parses until it finds the corresponding end tag, eg: for a tag named ``mytag`` it will parse until ``endmytag``. The decorated func's return value is used to render the parsed content and takes three arguments - the parsed content between the start and end tags, the template context and the tag token. """ @wraps(tag_func) def tag_wrapper(parser, token): class ToEndTagNode(template.Node): def __init__(self): end_name = "end%s" % tag_func.__name__ self.nodelist = parser.parse((end_name,)) parser.delete_first_token() def render(self, context): args = (self.nodelist.render(context), context, token) return tag_func(*args[:tag_func.__code__.co_argcount]) return ToEndTagNode() return self.tag(tag_wrapper)