from urllib.parse import quote, urljoin
from django import template
from django.apps import apps
from django.utils.encoding import iri_to_uri
from django.utils.html import conditional_escape
register = template.Library()
class PrefixNode(template.Node):
def __repr__(self):
return "<PrefixNode for %r>" % self.name
def __init__(self, varname=None, name=None):
if name is None:
raise template.TemplateSyntaxError(
"Prefix nodes must be given a name to return.")
self.varname = varname
self.name = name
@classmethod
def handle_token(cls, parser, token, name):
"""
Class method to parse prefix node and return a Node.
"""
# token.split_contents() isn't useful here because tags using this method don't accept variable as arguments
tokens = token.contents.split()
if len(tokens) > 1 and tokens[1] != 'as':
raise template.TemplateSyntaxError(
"First argument in '%s' must be 'as'" % tokens[0])
if len(tokens) > 1:
varname = tokens[2]
else:
varname = None
return cls(varname, name)
@classmethod
def handle_simple(cls, name):
try:
from django.conf import settings
except ImportError:
prefix = ''
else:
prefix = iri_to_uri(getattr(settings, name, ''))
return prefix
def render(self, context):
prefix = self.handle_simple(self.name)
if self.varname is None:
return prefix
context[self.varname] = prefix
return ''
@register.tag
def get_static_prefix(parser, token):
"""
Populate a template variable with the static prefix,
``settings.STATIC_URL``.
Usage::
{% get_static_prefix [as varname] %}
Examples::
{% get_static_prefix %}
{% get_static_prefix as static_prefix %}
"""
return PrefixNode.handle_token(parser, token, "STATIC_URL")
@register.tag
def get_media_prefix(parser, token):
"""
Populate a template variable with the media prefix,
``settings.MEDIA_URL``.
Usage::
{% get_media_prefix [as varname] %}
Examples::
{% get_media_prefix %}
{% get_media_prefix as media_prefix %}
"""
return PrefixNode.handle_token(parser, token, "MEDIA_URL")
class StaticNode(template.Node):
def __init__(self, varname=None, path=None):
if path is None:
raise template.TemplateSyntaxError(
"Static template nodes must be given a path to return.")
self.path = path
self.varname = varname
def url(self, context):
path = self.path.resolve(context)
return self.handle_simple(path)
def render(self, context):
url = self.url(context)
if context.autoescape:
url = conditional_escape(url)
if self.varname is None:
return url
context[self.varname] = url
return ''
@classmethod
def handle_simple(cls, path):
if apps.is_installed('django.contrib.staticfiles'):
from django.contrib.staticfiles.storage import staticfiles_storage
return staticfiles_storage.url(path)
else:
return urljoin(PrefixNode.handle_simple("STATIC_URL"), quote(path))
@classmethod
def handle_token(cls, parser, token):
"""
Class method to parse prefix node and return a Node.
"""
bits = token.split_contents()
if len(bits) < 2:
raise template.TemplateSyntaxError(
"'%s' takes at least one argument (path to file)" % bits[0])
path = parser.compile_filter(bits[1])
if len(bits) >= 2 and bits[-2] == 'as':
varname = bits[3]
else:
varname = None
return cls(varname, path)
@register.tag('static')
def do_static(parser, token):
"""
Join the given path with the STATIC_URL setting.
Usage::
{% static path [as varname] %}
Examples::
{% static "myapp/css/base.css" %}
{% static variable_with_path %}
{% static "myapp/css/base.css" as admin_base_css %}
{% static variable_with_path as varname %}
"""
return StaticNode.handle_token(parser, token)
def static(path):
"""
Given a relative path to a static asset, return the absolute path to the
asset.
"""
return StaticNode.handle_simple(path)