anki/oldanki/template/template.py
2013-01-08 09:43:29 +09:00

157 lines
4.8 KiB
Python

import re
import cgi
import collections
modifiers = {}
def modifier(symbol):
"""Decorator for associating a function with a Mustache tag modifier.
@modifier('P')
def render_tongue(self, tag_name=None, context=None):
return ":P %s" % tag_name
{{P yo }} => :P yo
"""
def set_modifier(func):
modifiers[symbol] = func
return func
return set_modifier
def get_or_attr(obj, name, default=None):
try:
return obj[name]
except KeyError:
return default
except:
try:
return getattr(obj, name)
except AttributeError:
return default
class Template(object):
# The regular expression used to find a #section
section_re = None
# The regular expression used to find a tag.
tag_re = None
# Opening tag delimiter
otag = '{{'
# Closing tag delimiter
ctag = '}}'
def __init__(self, template, context=None):
self.template = template
self.context = context or {}
self.compile_regexps()
def render(self, template=None, context=None, encoding=None):
"""Turns a Mustache template into something wonderful."""
template = template or self.template
context = context or self.context
template = self.render_sections(template, context)
result = self.render_tags(template, context)
if encoding is not None:
result = result.encode(encoding)
return result
def compile_regexps(self):
"""Compiles our section and tag regular expressions."""
tags = { 'otag': re.escape(self.otag), 'ctag': re.escape(self.ctag) }
section = r"%(otag)s[\#|^]([^\}]*)%(ctag)s(.+?)%(otag)s/\1%(ctag)s"
self.section_re = re.compile(section % tags, re.M|re.S)
tag = r"%(otag)s(#|=|&|!|>|\{)?(.+?)\1?%(ctag)s+"
self.tag_re = re.compile(tag % tags)
def render_sections(self, template, context):
"""Expands sections."""
while 1:
match = self.section_re.search(template)
if match is None:
break
section, section_name, inner = match.group(0, 1, 2)
section_name = section_name.strip()
it = get_or_attr(context, section_name, None)
replacer = ''
# if it and isinstance(it, collections.Callable):
# replacer = it(inner)
if it and not hasattr(it, '__iter__'):
if section[2] != '^':
replacer = inner
elif it and hasattr(it, 'keys') and hasattr(it, '__getitem__'):
if section[2] != '^':
replacer = self.render(inner, it)
elif it:
insides = []
for item in it:
insides.append(self.render(inner, item))
replacer = ''.join(insides)
elif not it and section[2] == '^':
replacer = inner
template = template.replace(section, replacer)
return template
def render_tags(self, template, context):
"""Renders all the tags in a template for a context."""
while 1:
match = self.tag_re.search(template)
if match is None:
break
tag, tag_type, tag_name = match.group(0, 1, 2)
tag_name = tag_name.strip()
try:
func = modifiers[tag_type]
replacement = func(self, tag_name, context)
template = template.replace(tag, replacement)
except:
return u"{{invalid template}}"
return template
@modifier('{')
def render_tag(self, tag_name, context):
"""Given a tag name and context, finds, escapes, and renders the tag."""
raw = get_or_attr(context, tag_name, '')
if not raw and raw is not 0:
return ''
return re.sub("^<span.+?>(.*)</span>", "\\1", raw)
@modifier('!')
def render_comment(self, tag_name=None, context=None):
"""Rendering a comment always returns nothing."""
return ''
@modifier(None)
def render_unescaped(self, tag_name=None, context=None):
"""Render a tag without escaping it."""
return unicode(get_or_attr(context, tag_name, '{unknown field %s}' % tag_name))
# @modifier('>')
# def render_partial(self, tag_name=None, context=None):
# """Renders a partial within the current context."""
# # Import view here to avoid import loop
# from pystache.view import View
# view = View(context=context)
# view.template_name = tag_name
# return view.render()
@modifier('=')
def render_delimiter(self, tag_name=None, context=None):
"""Changes the Mustache delimiter."""
self.otag, self.ctag = tag_name.split(' ')
self.compile_regexps()
return ''