2005-07-13 09:25:57 +08:00
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"""
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2005-08-10 06:43:34 +08:00
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This is the Django template system.
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2005-07-13 09:25:57 +08:00
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How it works:
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The tokenize() function converts a template string (i.e., a string containing
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markup with custom template tags) to tokens, which can be either plain text
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(TOKEN_TEXT), variables (TOKEN_VAR) or block statements (TOKEN_BLOCK).
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The Parser() class takes a list of tokens in its constructor, and its parse()
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method returns a compiled template -- which is, under the hood, a list of
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Node objects.
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Each Node is responsible for creating some sort of output -- e.g. simple text
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(TextNode), variable values in a given context (VariableNode), results of basic
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logic (IfNode), results of looping (ForNode), or anything else. The core Node
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types are TextNode, VariableNode, IfNode and ForNode, but plugin modules can
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define their own custom node types.
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Each Node has a render() method, which takes a Context and returns a string of
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the rendered node. For example, the render() method of a Variable Node returns
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the variable's value as a string. The render() method of an IfNode returns the
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rendered output of whatever was inside the loop, recursively.
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The Template class is a convenient wrapper that takes care of template
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compilation and rendering.
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Usage:
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The only thing you should ever use directly in this file is the Template class.
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Create a compiled template object with a template_string, then call render()
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with a context. In the compilation stage, the TemplateSyntaxError exception
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will be raised if the template doesn't have proper syntax.
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Sample code:
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>>> import template
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>>> s = '''
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... <html>
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... {% if test %}
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... <h1>{{ varvalue }}</h1>
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... {% endif %}
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... </html>
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... '''
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>>> t = template.Template(s)
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(t is now a compiled template, and its render() method can be called multiple
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times with multiple contexts)
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>>> c = template.Context({'test':True, 'varvalue': 'Hello'})
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>>> t.render(c)
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'\n<html>\n\n <h1>Hello</h1>\n\n</html>\n'
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>>> c = template.Context({'test':False, 'varvalue': 'Hello'})
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>>> t.render(c)
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'\n<html>\n\n</html>\n'
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"""
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import re
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2005-10-06 10:27:08 +08:00
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from django.conf.settings import DEFAULT_CHARSET
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2005-07-13 09:25:57 +08:00
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__all__ = ('Template','Context','compile_string')
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TOKEN_TEXT = 0
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TOKEN_VAR = 1
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TOKEN_BLOCK = 2
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# template syntax constants
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FILTER_SEPARATOR = '|'
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FILTER_ARGUMENT_SEPARATOR = ':'
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VARIABLE_ATTRIBUTE_SEPARATOR = '.'
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BLOCK_TAG_START = '{%'
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BLOCK_TAG_END = '%}'
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VARIABLE_TAG_START = '{{'
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VARIABLE_TAG_END = '}}'
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ALLOWED_VARIABLE_CHARS = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_.'
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# match a variable or block tag and capture the entire tag, including start/end delimiters
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tag_re = re.compile('(%s.*?%s|%s.*?%s)' % (re.escape(BLOCK_TAG_START), re.escape(BLOCK_TAG_END),
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re.escape(VARIABLE_TAG_START), re.escape(VARIABLE_TAG_END)))
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# global dict used by register_tag; maps custom tags to callback functions
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registered_tags = {}
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# global dict used by register_filter; maps custom filters to callback functions
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registered_filters = {}
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class TemplateSyntaxError(Exception):
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pass
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class ContextPopException(Exception):
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"pop() has been called more times than push()"
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pass
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class TemplateDoesNotExist(Exception):
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pass
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class VariableDoesNotExist(Exception):
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pass
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class SilentVariableFailure(Exception):
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"Any function raising this exception will be ignored by resolve_variable"
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pass
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class Template:
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def __init__(self, template_string):
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"Compilation stage"
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self.nodelist = compile_string(template_string)
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def __iter__(self):
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for node in self.nodelist:
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for subnode in node:
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yield subnode
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def render(self, context):
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"Display stage -- can be called many times"
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return self.nodelist.render(context)
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def compile_string(template_string):
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"Compiles template_string into NodeList ready for rendering"
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tokens = tokenize(template_string)
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parser = Parser(tokens)
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return parser.parse()
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class Context:
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"A stack container for variable context"
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2005-09-18 07:06:16 +08:00
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def __init__(self, dict=None):
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dict = dict or {}
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2005-07-13 09:25:57 +08:00
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self.dicts = [dict]
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def __repr__(self):
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return repr(self.dicts)
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def __iter__(self):
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for d in self.dicts:
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yield d
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def push(self):
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self.dicts = [{}] + self.dicts
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def pop(self):
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if len(self.dicts) == 1:
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raise ContextPopException
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del self.dicts[0]
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def __setitem__(self, key, value):
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"Set a variable in the current context"
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self.dicts[0][key] = value
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def __getitem__(self, key):
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"Get a variable's value, starting at the current context and going upward"
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for dict in self.dicts:
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if dict.has_key(key):
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return dict[key]
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return ''
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def __delitem__(self, key):
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"Delete a variable from the current context"
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del self.dicts[0][key]
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def has_key(self, key):
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for dict in self.dicts:
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if dict.has_key(key):
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return True
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return False
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def update(self, other_dict):
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"Like dict.update(). Pushes an entire dictionary's keys and values onto the context."
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self.dicts = [other_dict] + self.dicts
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class Token:
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def __init__(self, token_type, contents):
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"The token_type must be TOKEN_TEXT, TOKEN_VAR or TOKEN_BLOCK"
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self.token_type, self.contents = token_type, contents
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def __str__(self):
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return '<%s token: "%s...">' % (
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{TOKEN_TEXT:'Text', TOKEN_VAR:'Var', TOKEN_BLOCK:'Block'}[self.token_type],
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self.contents[:20].replace('\n', '')
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)
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def tokenize(template_string):
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"Return a list of tokens from a given template_string"
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# remove all empty strings, because the regex has a tendency to add them
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bits = filter(None, tag_re.split(template_string))
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return map(create_token, bits)
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def create_token(token_string):
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"Convert the given token string into a new Token object and return it"
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if token_string.startswith(VARIABLE_TAG_START):
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return Token(TOKEN_VAR, token_string[len(VARIABLE_TAG_START):-len(VARIABLE_TAG_END)].strip())
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elif token_string.startswith(BLOCK_TAG_START):
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return Token(TOKEN_BLOCK, token_string[len(BLOCK_TAG_START):-len(BLOCK_TAG_END)].strip())
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else:
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return Token(TOKEN_TEXT, token_string)
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class Parser:
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def __init__(self, tokens):
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self.tokens = tokens
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def parse(self, parse_until=[]):
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nodelist = NodeList()
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while self.tokens:
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token = self.next_token()
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if token.token_type == TOKEN_TEXT:
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nodelist.append(TextNode(token.contents))
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elif token.token_type == TOKEN_VAR:
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if not token.contents:
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raise TemplateSyntaxError, "Empty variable tag"
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nodelist.append(VariableNode(token.contents))
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elif token.token_type == TOKEN_BLOCK:
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if token.contents in parse_until:
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# put token back on token list so calling code knows why it terminated
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self.prepend_token(token)
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return nodelist
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try:
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command = token.contents.split()[0]
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except IndexError:
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raise TemplateSyntaxError, "Empty block tag"
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try:
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# execute callback function for this tag and append resulting node
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nodelist.append(registered_tags[command](self, token))
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except KeyError:
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raise TemplateSyntaxError, "Invalid block tag: '%s'" % command
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if parse_until:
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raise TemplateSyntaxError, "Unclosed tag(s): '%s'" % ', '.join(parse_until)
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return nodelist
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def next_token(self):
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return self.tokens.pop(0)
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def prepend_token(self, token):
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self.tokens.insert(0, token)
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def delete_first_token(self):
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del self.tokens[0]
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2005-11-04 12:59:46 +08:00
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class TokenParser:
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"""
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2005-11-07 06:22:02 +08:00
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Subclass this and implement the top() method to parse a template line. When
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instantiating the parser, pass in the line from the Django template parser.
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2005-11-04 12:59:46 +08:00
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2005-11-07 06:22:02 +08:00
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The parser's "tagname" instance-variable stores the name of the tag that
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the filter was called with.
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2005-11-04 12:59:46 +08:00
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"""
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def __init__(self, subject):
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self.subject = subject
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self.pointer = 0
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self.backout = []
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self.tagname = self.tag()
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def top(self):
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2005-11-07 06:22:02 +08:00
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"Overload this method to do the actual parsing and return the result."
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2005-11-04 12:59:46 +08:00
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raise NotImplemented
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def more(self):
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2005-11-07 06:22:02 +08:00
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"Returns True if there is more stuff in the tag."
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2005-11-04 12:59:46 +08:00
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return self.pointer < len(self.subject)
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def back(self):
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2005-11-07 06:22:02 +08:00
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"Undoes the last microparser. Use this for lookahead and backtracking."
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2005-11-04 12:59:46 +08:00
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if not len(self.backout):
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raise TemplateSyntaxError, "back called without some previous parsing"
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self.pointer = self.backout.pop()
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def tag(self):
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2005-11-07 06:22:02 +08:00
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"A microparser that just returns the next tag from the line."
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2005-11-04 12:59:46 +08:00
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subject = self.subject
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i = self.pointer
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if i >= len(subject):
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raise TemplateSyntaxError, "expected another tag, found end of string: %s" % subject
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p = i
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while i < len(subject) and subject[i] not in (' ', '\t'):
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i += 1
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s = subject[p:i]
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while i < len(subject) and subject[i] in (' ', '\t'):
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i += 1
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self.backout.append(self.pointer)
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self.pointer = i
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return s
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def value(self):
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2005-11-07 06:22:02 +08:00
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"A microparser that parses for a value: some string constant or variable name."
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2005-11-04 12:59:46 +08:00
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subject = self.subject
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i = self.pointer
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if i >= len(subject):
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2005-11-07 06:22:02 +08:00
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raise TemplateSyntaxError, "Searching for value. Expected another value but found end of string: %s" % subject
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2005-11-04 12:59:46 +08:00
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if subject[i] in ('"', "'"):
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p = i
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i += 1
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while i < len(subject) and subject[i] != subject[p]:
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i += 1
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if i >= len(subject):
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2005-11-07 06:22:02 +08:00
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raise TemplateSyntaxError, "Searching for value. Unexpected end of string in column %d: %s" % subject
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2005-11-04 12:59:46 +08:00
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i += 1
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res = subject[p:i]
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while i < len(subject) and subject[i] in (' ', '\t'):
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i += 1
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self.backout.append(self.pointer)
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self.pointer = i
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return res
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else:
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p = i
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while i < len(subject) and subject[i] not in (' ', '\t'):
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i += 1
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s = subject[p:i]
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while i < len(subject) and subject[i] in (' ', '\t'):
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i += 1
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self.backout.append(self.pointer)
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self.pointer = i
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return s
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2005-07-13 09:25:57 +08:00
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class FilterParser:
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2005-11-07 06:22:02 +08:00
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"""
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Parses a variable token and its optional filters (all as a single string),
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and return a list of tuples of the filter name and arguments.
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Sample:
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>>> token = 'variable|default:"Default value"|date:"Y-m-d"'
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|
|
>>> 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.
|
2005-07-13 09:25:57 +08:00
|
|
|
"""
|
|
|
|
|
def __init__(self, s):
|
|
|
|
|
self.s = s
|
|
|
|
|
self.i = -1
|
|
|
|
|
self.current = ''
|
|
|
|
|
self.filters = []
|
|
|
|
|
self.current_filter_name = None
|
|
|
|
|
self.current_filter_arg = None
|
2005-11-07 06:22:02 +08:00
|
|
|
# First read the variable part. Decide whether we need to parse a
|
|
|
|
|
# string or a variable by peeking into the stream.
|
2005-11-04 12:59:46 +08:00
|
|
|
if self.peek_char() in ('_', '"', "'"):
|
|
|
|
|
self.var = self.read_constant_string_token()
|
|
|
|
|
else:
|
|
|
|
|
self.var = self.read_alphanumeric_token()
|
2005-07-13 09:25:57 +08:00
|
|
|
if not self.var:
|
|
|
|
|
raise TemplateSyntaxError, "Could not read variable name: '%s'" % self.s
|
|
|
|
|
if self.var.find(VARIABLE_ATTRIBUTE_SEPARATOR + '_') > -1 or self.var[0] == '_':
|
|
|
|
|
raise TemplateSyntaxError, "Variables and attributes may not begin with underscores: '%s'" % self.var
|
|
|
|
|
# Have we reached the end?
|
|
|
|
|
if self.current is None:
|
|
|
|
|
return
|
|
|
|
|
if self.current != FILTER_SEPARATOR:
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting '%s') '%s'" % (FILTER_SEPARATOR, self.current)
|
|
|
|
|
# We have a filter separator; start reading the filters
|
|
|
|
|
self.read_filters()
|
|
|
|
|
|
2005-11-04 12:59:46 +08:00
|
|
|
def peek_char(self):
|
|
|
|
|
try:
|
|
|
|
|
return self.s[self.i+1]
|
|
|
|
|
except IndexError:
|
|
|
|
|
return None
|
|
|
|
|
|
2005-07-13 09:25:57 +08:00
|
|
|
def next_char(self):
|
|
|
|
|
self.i = self.i + 1
|
|
|
|
|
try:
|
|
|
|
|
self.current = self.s[self.i]
|
|
|
|
|
except IndexError:
|
|
|
|
|
self.current = None
|
|
|
|
|
|
2005-11-04 12:59:46 +08:00
|
|
|
def read_constant_string_token(self):
|
2005-11-07 06:22:02 +08:00
|
|
|
"""
|
|
|
|
|
Reads a constant string that must be delimited by either " or '
|
|
|
|
|
characters. The string is returned with its delimiters.
|
|
|
|
|
"""
|
2005-11-04 12:59:46 +08:00
|
|
|
val = ''
|
|
|
|
|
qchar = None
|
|
|
|
|
i18n = False
|
|
|
|
|
self.next_char()
|
|
|
|
|
if self.current == '_':
|
|
|
|
|
i18n = True
|
2005-11-07 06:22:02 +08:00
|
|
|
self.next_char()
|
2005-11-04 12:59:46 +08:00
|
|
|
if self.current != '(':
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting '(') '%s'" % self.current
|
|
|
|
|
self.next_char()
|
|
|
|
|
if not self.current in ('"', "'"):
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting '\"' or ''') '%s'" % self.current
|
|
|
|
|
qchar = self.current
|
|
|
|
|
val += qchar
|
|
|
|
|
while 1:
|
|
|
|
|
self.next_char()
|
|
|
|
|
if self.current == qchar:
|
|
|
|
|
break
|
|
|
|
|
val += self.current
|
|
|
|
|
val += self.current
|
|
|
|
|
self.next_char()
|
|
|
|
|
if i18n:
|
|
|
|
|
if self.current != ')':
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting ')') '%s'" % self.current
|
|
|
|
|
self.next_char()
|
|
|
|
|
val = qchar+_(val.strip(qchar))+qchar
|
|
|
|
|
return val
|
|
|
|
|
|
2005-07-13 09:25:57 +08:00
|
|
|
def read_alphanumeric_token(self):
|
2005-11-07 06:22:02 +08:00
|
|
|
"""
|
|
|
|
|
Reads a variable name or filter name, which are continuous strings of
|
|
|
|
|
alphanumeric characters + the underscore.
|
|
|
|
|
"""
|
2005-07-13 09:25:57 +08:00
|
|
|
var = ''
|
|
|
|
|
while 1:
|
|
|
|
|
self.next_char()
|
|
|
|
|
if self.current is None:
|
|
|
|
|
break
|
|
|
|
|
if self.current not in ALLOWED_VARIABLE_CHARS:
|
|
|
|
|
break
|
|
|
|
|
var += self.current
|
|
|
|
|
return var
|
|
|
|
|
|
|
|
|
|
def read_filters(self):
|
|
|
|
|
while 1:
|
|
|
|
|
filter_name, arg = self.read_filter()
|
|
|
|
|
if not registered_filters.has_key(filter_name):
|
|
|
|
|
raise TemplateSyntaxError, "Invalid filter: '%s'" % filter_name
|
|
|
|
|
if registered_filters[filter_name][1] == True and arg is None:
|
|
|
|
|
raise TemplateSyntaxError, "Filter '%s' requires an argument" % filter_name
|
|
|
|
|
if registered_filters[filter_name][1] == False and arg is not None:
|
2005-09-11 23:18:04 +08:00
|
|
|
raise TemplateSyntaxError, "Filter '%s' should not have an argument (argument is %r)" % (filter_name, arg)
|
2005-07-13 09:25:57 +08:00
|
|
|
self.filters.append((filter_name, arg))
|
|
|
|
|
if self.current is None:
|
|
|
|
|
break
|
|
|
|
|
|
|
|
|
|
def read_filter(self):
|
|
|
|
|
self.current_filter_name = self.read_alphanumeric_token()
|
2005-09-11 23:18:04 +08:00
|
|
|
self.current_filter_arg = None
|
2005-07-13 09:25:57 +08:00
|
|
|
# Have we reached the end?
|
|
|
|
|
if self.current is None:
|
|
|
|
|
return (self.current_filter_name, None)
|
|
|
|
|
# Does the filter have an argument?
|
|
|
|
|
if self.current == FILTER_ARGUMENT_SEPARATOR:
|
|
|
|
|
self.current_filter_arg = self.read_arg()
|
|
|
|
|
return (self.current_filter_name, self.current_filter_arg)
|
|
|
|
|
# Next thing MUST be a pipe
|
|
|
|
|
if self.current != FILTER_SEPARATOR:
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting '%s') '%s'" % (FILTER_SEPARATOR, self.current)
|
|
|
|
|
return (self.current_filter_name, self.current_filter_arg)
|
|
|
|
|
|
|
|
|
|
def read_arg(self):
|
2005-11-04 12:59:46 +08:00
|
|
|
# First read a " or a _("
|
2005-07-13 09:25:57 +08:00
|
|
|
self.next_char()
|
2005-11-04 12:59:46 +08:00
|
|
|
translated = False
|
|
|
|
|
if self.current == '_':
|
|
|
|
|
self.next_char()
|
|
|
|
|
if self.current != '(':
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting '(') '%s'" % self.current
|
|
|
|
|
translated = True
|
|
|
|
|
self.next_char()
|
2005-07-13 09:25:57 +08:00
|
|
|
if self.current != '"':
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting '\"') '%s'" % self.current
|
|
|
|
|
self.escaped = False
|
|
|
|
|
arg = ''
|
|
|
|
|
while 1:
|
|
|
|
|
self.next_char()
|
|
|
|
|
if self.current == '"' and not self.escaped:
|
|
|
|
|
break
|
|
|
|
|
if self.current == '\\' and not self.escaped:
|
|
|
|
|
self.escaped = True
|
|
|
|
|
continue
|
|
|
|
|
if self.current == '\\' and self.escaped:
|
|
|
|
|
arg += '\\'
|
|
|
|
|
self.escaped = False
|
|
|
|
|
continue
|
|
|
|
|
if self.current == '"' and self.escaped:
|
|
|
|
|
arg += '"'
|
|
|
|
|
self.escaped = False
|
|
|
|
|
continue
|
|
|
|
|
if self.escaped and self.current not in '\\"':
|
|
|
|
|
raise TemplateSyntaxError, "Unescaped backslash in '%s'" % self.s
|
|
|
|
|
if self.current is None:
|
|
|
|
|
raise TemplateSyntaxError, "Unexpected end of argument in '%s'" % self.s
|
|
|
|
|
arg += self.current
|
|
|
|
|
# self.current must now be '"'
|
|
|
|
|
self.next_char()
|
2005-11-04 12:59:46 +08:00
|
|
|
if translated:
|
|
|
|
|
if self.current != ')':
|
|
|
|
|
raise TemplateSyntaxError, "Bad character (expecting ')') '%s'" % self.current
|
|
|
|
|
self.next_char()
|
|
|
|
|
arg = _(arg)
|
2005-07-13 09:25:57 +08:00
|
|
|
return arg
|
|
|
|
|
|
|
|
|
|
def get_filters_from_token(token):
|
|
|
|
|
"Convenient wrapper for FilterParser"
|
|
|
|
|
p = FilterParser(token)
|
|
|
|
|
return (p.var, p.filters)
|
|
|
|
|
|
|
|
|
|
def resolve_variable(path, context):
|
|
|
|
|
"""
|
|
|
|
|
Returns the resolved variable, which may contain attribute syntax, within
|
2005-09-01 10:18:04 +08:00
|
|
|
the given context. The variable may be a hard-coded string (if it begins
|
|
|
|
|
and ends with single or double quote marks).
|
2005-07-13 09:25:57 +08:00
|
|
|
|
|
|
|
|
>>> 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 '.')
|
|
|
|
|
"""
|
2005-09-01 10:18:04 +08:00
|
|
|
if 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):
|
2005-07-13 09:25:57 +08:00
|
|
|
current = ''
|
2005-09-01 10:18:04 +08:00
|
|
|
else:
|
|
|
|
|
try: # method call (assuming no args required)
|
|
|
|
|
current = current()
|
|
|
|
|
except SilentVariableFailure:
|
|
|
|
|
current = ''
|
|
|
|
|
except TypeError: # arguments *were* required
|
|
|
|
|
current = '' # invalid method call
|
|
|
|
|
except (TypeError, AttributeError):
|
|
|
|
|
try: # list-index lookup
|
|
|
|
|
current = current[int(bits[0])]
|
|
|
|
|
except (IndexError, ValueError, KeyError):
|
|
|
|
|
raise VariableDoesNotExist, "Failed lookup for key [%s] in %r" % (bits[0], current) # missing attribute
|
|
|
|
|
del bits[0]
|
2005-07-13 09:25:57 +08:00
|
|
|
return current
|
|
|
|
|
|
|
|
|
|
def resolve_variable_with_filters(var_string, context):
|
|
|
|
|
"""
|
|
|
|
|
var_string is a full variable expression with optional filters, like:
|
|
|
|
|
a.b.c|lower|date:"y/m/d"
|
|
|
|
|
This function resolves the variable in the context, applies all filters and
|
|
|
|
|
returns the object.
|
|
|
|
|
"""
|
|
|
|
|
var, filters = get_filters_from_token(var_string)
|
|
|
|
|
try:
|
|
|
|
|
obj = resolve_variable(var, context)
|
|
|
|
|
except VariableDoesNotExist:
|
|
|
|
|
obj = ''
|
|
|
|
|
for name, arg in filters:
|
|
|
|
|
obj = registered_filters[name][0](obj, arg)
|
|
|
|
|
return obj
|
|
|
|
|
|
|
|
|
|
class Node:
|
|
|
|
|
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(node.render(context))
|
|
|
|
|
else:
|
|
|
|
|
bits.append(node)
|
|
|
|
|
return ''.join(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
|
|
|
|
|
|
|
|
|
|
class TextNode(Node):
|
|
|
|
|
def __init__(self, s):
|
|
|
|
|
self.s = s
|
|
|
|
|
|
|
|
|
|
def __repr__(self):
|
|
|
|
|
return "<Text Node: '%s'>" % self.s[:25]
|
|
|
|
|
|
|
|
|
|
def render(self, context):
|
|
|
|
|
return self.s
|
|
|
|
|
|
|
|
|
|
class VariableNode(Node):
|
|
|
|
|
def __init__(self, var_string):
|
|
|
|
|
self.var_string = var_string
|
|
|
|
|
|
|
|
|
|
def __repr__(self):
|
|
|
|
|
return "<Variable Node: %s>" % self.var_string
|
|
|
|
|
|
|
|
|
|
def render(self, context):
|
|
|
|
|
output = resolve_variable_with_filters(self.var_string, context)
|
|
|
|
|
# Check type so that we don't run str() on a Unicode object
|
|
|
|
|
if not isinstance(output, basestring):
|
|
|
|
|
output = str(output)
|
|
|
|
|
elif isinstance(output, unicode):
|
2005-10-06 10:27:08 +08:00
|
|
|
output = output.encode(DEFAULT_CHARSET)
|
2005-07-13 09:25:57 +08:00
|
|
|
return output
|
|
|
|
|
|
|
|
|
|
def register_tag(token_command, callback_function):
|
|
|
|
|
registered_tags[token_command] = callback_function
|
|
|
|
|
|
|
|
|
|
def unregister_tag(token_command):
|
|
|
|
|
del registered_tags[token_command]
|
|
|
|
|
|
|
|
|
|
def register_filter(filter_name, callback_function, has_arg):
|
|
|
|
|
registered_filters[filter_name] = (callback_function, has_arg)
|
|
|
|
|
|
|
|
|
|
def unregister_filter(filter_name):
|
|
|
|
|
del registered_filters[filter_name]
|
|
|
|
|
|
|
|
|
|
import defaulttags
|
|
|
|
|
import defaultfilters
|
