# mako/parsetree.py # Copyright 2006-2019 the Mako authors and contributors # # This module is part of Mako and is released under # the MIT License: http://www.opensource.org/licenses/mit-license.php """defines the parse tree components for Mako templates.""" import re from mako import ast from mako import compat from mako import exceptions from mako import filters from mako import util class Node(object): """base class for a Node in the parse tree.""" def __init__(self, source, lineno, pos, filename): self.source = source self.lineno = lineno self.pos = pos self.filename = filename @property def exception_kwargs(self): return { "source": self.source, "lineno": self.lineno, "pos": self.pos, "filename": self.filename, } def get_children(self): return [] def accept_visitor(self, visitor): def traverse(node): for n in node.get_children(): n.accept_visitor(visitor) method = getattr(visitor, "visit" + self.__class__.__name__, traverse) method(self) class TemplateNode(Node): """a 'container' node that stores the overall collection of nodes.""" def __init__(self, filename): super(TemplateNode, self).__init__("", 0, 0, filename) self.nodes = [] self.page_attributes = {} def get_children(self): return self.nodes def __repr__(self): return "TemplateNode(%s, %r)" % ( util.sorted_dict_repr(self.page_attributes), self.nodes, ) class ControlLine(Node): """defines a control line, a line-oriented python line or end tag. e.g.:: % if foo: (markup) % endif """ has_loop_context = False def __init__(self, keyword, isend, text, **kwargs): super(ControlLine, self).__init__(**kwargs) self.text = text self.keyword = keyword self.isend = isend self.is_primary = keyword in ["for", "if", "while", "try", "with"] self.nodes = [] if self.isend: self._declared_identifiers = [] self._undeclared_identifiers = [] else: code = ast.PythonFragment(text, **self.exception_kwargs) self._declared_identifiers = code.declared_identifiers self._undeclared_identifiers = code.undeclared_identifiers def get_children(self): return self.nodes def declared_identifiers(self): return self._declared_identifiers def undeclared_identifiers(self): return self._undeclared_identifiers def is_ternary(self, keyword): """return true if the given keyword is a ternary keyword for this ControlLine""" return keyword in { "if": set(["else", "elif"]), "try": set(["except", "finally"]), "for": set(["else"]), }.get(self.keyword, []) def __repr__(self): return "ControlLine(%r, %r, %r, %r)" % ( self.keyword, self.text, self.isend, (self.lineno, self.pos), ) class Text(Node): """defines plain text in the template.""" def __init__(self, content, **kwargs): super(Text, self).__init__(**kwargs) self.content = content def __repr__(self): return "Text(%r, %r)" % (self.content, (self.lineno, self.pos)) class Code(Node): """defines a Python code block, either inline or module level. e.g.:: inline: <% x = 12 %> module level: <%! import logger %> """ def __init__(self, text, ismodule, **kwargs): super(Code, self).__init__(**kwargs) self.text = text self.ismodule = ismodule self.code = ast.PythonCode(text, **self.exception_kwargs) def declared_identifiers(self): return self.code.declared_identifiers def undeclared_identifiers(self): return self.code.undeclared_identifiers def __repr__(self): return "Code(%r, %r, %r)" % ( self.text, self.ismodule, (self.lineno, self.pos), ) class Comment(Node): """defines a comment line. # this is a comment """ def __init__(self, text, **kwargs): super(Comment, self).__init__(**kwargs) self.text = text def __repr__(self): return "Comment(%r, %r)" % (self.text, (self.lineno, self.pos)) class Expression(Node): """defines an inline expression. ${x+y} """ def __init__(self, text, escapes, **kwargs): super(Expression, self).__init__(**kwargs) self.text = text self.escapes = escapes self.escapes_code = ast.ArgumentList(escapes, **self.exception_kwargs) self.code = ast.PythonCode(text, **self.exception_kwargs) def declared_identifiers(self): return [] def undeclared_identifiers(self): # TODO: make the "filter" shortcut list configurable at parse/gen time return self.code.undeclared_identifiers.union( self.escapes_code.undeclared_identifiers.difference( set(filters.DEFAULT_ESCAPES.keys()) ) ).difference(self.code.declared_identifiers) def __repr__(self): return "Expression(%r, %r, %r)" % ( self.text, self.escapes_code.args, (self.lineno, self.pos), ) class _TagMeta(type): """metaclass to allow Tag to produce a subclass according to its keyword""" _classmap = {} def __init__(cls, clsname, bases, dict_): if getattr(cls, "__keyword__", None) is not None: cls._classmap[cls.__keyword__] = cls super(_TagMeta, cls).__init__(clsname, bases, dict_) def __call__(cls, keyword, attributes, **kwargs): if ":" in keyword: ns, defname = keyword.split(":") return type.__call__( CallNamespaceTag, ns, defname, attributes, **kwargs ) try: cls = _TagMeta._classmap[keyword] except KeyError: raise exceptions.CompileException( "No such tag: '%s'" % keyword, source=kwargs["source"], lineno=kwargs["lineno"], pos=kwargs["pos"], filename=kwargs["filename"], ) return type.__call__(cls, keyword, attributes, **kwargs) class Tag(compat.with_metaclass(_TagMeta, Node)): """abstract base class for tags. e.g.:: <%sometag/> <%someothertag> stuff """ __keyword__ = None def __init__( self, keyword, attributes, expressions, nonexpressions, required, **kwargs ): r"""construct a new Tag instance. this constructor not called directly, and is only called by subclasses. :param keyword: the tag keyword :param attributes: raw dictionary of attribute key/value pairs :param expressions: a set of identifiers that are legal attributes, which can also contain embedded expressions :param nonexpressions: a set of identifiers that are legal attributes, which cannot contain embedded expressions :param \**kwargs: other arguments passed to the Node superclass (lineno, pos) """ super(Tag, self).__init__(**kwargs) self.keyword = keyword self.attributes = attributes self._parse_attributes(expressions, nonexpressions) missing = [r for r in required if r not in self.parsed_attributes] if len(missing): raise exceptions.CompileException( "Missing attribute(s): %s" % ",".join([repr(m) for m in missing]), **self.exception_kwargs ) self.parent = None self.nodes = [] def is_root(self): return self.parent is None def get_children(self): return self.nodes def _parse_attributes(self, expressions, nonexpressions): undeclared_identifiers = set() self.parsed_attributes = {} for key in self.attributes: if key in expressions: expr = [] for x in re.compile(r"(\${.+?})", re.S).split( self.attributes[key] ): m = re.compile(r"^\${(.+?)}$", re.S).match(x) if m: code = ast.PythonCode( m.group(1).rstrip(), **self.exception_kwargs ) # we aren't discarding "declared_identifiers" here, # which we do so that list comprehension-declared # variables aren't counted. As yet can't find a # condition that requires it here. undeclared_identifiers = undeclared_identifiers.union( code.undeclared_identifiers ) expr.append("(%s)" % m.group(1)) else: if x: expr.append(repr(x)) self.parsed_attributes[key] = " + ".join(expr) or repr("") elif key in nonexpressions: if re.search(r"\${.+?}", self.attributes[key]): raise exceptions.CompileException( "Attibute '%s' in tag '%s' does not allow embedded " "expressions" % (key, self.keyword), **self.exception_kwargs ) self.parsed_attributes[key] = repr(self.attributes[key]) else: raise exceptions.CompileException( "Invalid attribute for tag '%s': '%s'" % (self.keyword, key), **self.exception_kwargs ) self.expression_undeclared_identifiers = undeclared_identifiers def declared_identifiers(self): return [] def undeclared_identifiers(self): return self.expression_undeclared_identifiers def __repr__(self): return "%s(%r, %s, %r, %r)" % ( self.__class__.__name__, self.keyword, util.sorted_dict_repr(self.attributes), (self.lineno, self.pos), self.nodes, ) class IncludeTag(Tag): __keyword__ = "include" def __init__(self, keyword, attributes, **kwargs): super(IncludeTag, self).__init__( keyword, attributes, ("file", "import", "args"), (), ("file",), **kwargs ) self.page_args = ast.PythonCode( "__DUMMY(%s)" % attributes.get("args", ""), **self.exception_kwargs ) def declared_identifiers(self): return [] def undeclared_identifiers(self): identifiers = self.page_args.undeclared_identifiers.difference( set(["__DUMMY"]) ).difference(self.page_args.declared_identifiers) return identifiers.union( super(IncludeTag, self).undeclared_identifiers() ) class NamespaceTag(Tag): __keyword__ = "namespace" def __init__(self, keyword, attributes, **kwargs): super(NamespaceTag, self).__init__( keyword, attributes, ("file",), ("name", "inheritable", "import", "module"), (), **kwargs ) self.name = attributes.get("name", "__anon_%s" % hex(abs(id(self)))) if "name" not in attributes and "import" not in attributes: raise exceptions.CompileException( "'name' and/or 'import' attributes are required " "for <%namespace>", **self.exception_kwargs ) if "file" in attributes and "module" in attributes: raise exceptions.CompileException( "<%namespace> may only have one of 'file' or 'module'", **self.exception_kwargs ) def declared_identifiers(self): return [] class TextTag(Tag): __keyword__ = "text" def __init__(self, keyword, attributes, **kwargs): super(TextTag, self).__init__( keyword, attributes, (), ("filter"), (), **kwargs ) self.filter_args = ast.ArgumentList( attributes.get("filter", ""), **self.exception_kwargs ) def undeclared_identifiers(self): return self.filter_args.undeclared_identifiers.difference( filters.DEFAULT_ESCAPES.keys() ).union(self.expression_undeclared_identifiers) class DefTag(Tag): __keyword__ = "def" def __init__(self, keyword, attributes, **kwargs): expressions = ["buffered", "cached"] + [ c for c in attributes if c.startswith("cache_") ] super(DefTag, self).__init__( keyword, attributes, expressions, ("name", "filter", "decorator"), ("name",), **kwargs ) name = attributes["name"] if re.match(r"^[\w_]+$", name): raise exceptions.CompileException( "Missing parenthesis in %def", **self.exception_kwargs ) self.function_decl = ast.FunctionDecl( "def " + name + ":pass", **self.exception_kwargs ) self.name = self.function_decl.funcname self.decorator = attributes.get("decorator", "") self.filter_args = ast.ArgumentList( attributes.get("filter", ""), **self.exception_kwargs ) is_anonymous = False is_block = False @property def funcname(self): return self.function_decl.funcname def get_argument_expressions(self, **kw): return self.function_decl.get_argument_expressions(**kw) def declared_identifiers(self): return self.function_decl.allargnames def undeclared_identifiers(self): res = [] for c in self.function_decl.defaults: res += list( ast.PythonCode( c, **self.exception_kwargs ).undeclared_identifiers ) return ( set(res) .union( self.filter_args.undeclared_identifiers.difference( filters.DEFAULT_ESCAPES.keys() ) ) .union(self.expression_undeclared_identifiers) .difference(self.function_decl.allargnames) ) class BlockTag(Tag): __keyword__ = "block" def __init__(self, keyword, attributes, **kwargs): expressions = ["buffered", "cached", "args"] + [ c for c in attributes if c.startswith("cache_") ] super(BlockTag, self).__init__( keyword, attributes, expressions, ("name", "filter", "decorator"), (), **kwargs ) name = attributes.get("name") if name and not re.match(r"^[\w_]+$", name): raise exceptions.CompileException( "%block may not specify an argument signature", **self.exception_kwargs ) if not name and attributes.get("args", None): raise exceptions.CompileException( "Only named %blocks may specify args", **self.exception_kwargs ) self.body_decl = ast.FunctionArgs( attributes.get("args", ""), **self.exception_kwargs ) self.name = name self.decorator = attributes.get("decorator", "") self.filter_args = ast.ArgumentList( attributes.get("filter", ""), **self.exception_kwargs ) is_block = True @property def is_anonymous(self): return self.name is None @property def funcname(self): return self.name or "__M_anon_%d" % (self.lineno,) def get_argument_expressions(self, **kw): return self.body_decl.get_argument_expressions(**kw) def declared_identifiers(self): return self.body_decl.allargnames def undeclared_identifiers(self): return ( self.filter_args.undeclared_identifiers.difference( filters.DEFAULT_ESCAPES.keys() ) ).union(self.expression_undeclared_identifiers) class CallTag(Tag): __keyword__ = "call" def __init__(self, keyword, attributes, **kwargs): super(CallTag, self).__init__( keyword, attributes, ("args"), ("expr",), ("expr",), **kwargs ) self.expression = attributes["expr"] self.code = ast.PythonCode(self.expression, **self.exception_kwargs) self.body_decl = ast.FunctionArgs( attributes.get("args", ""), **self.exception_kwargs ) def declared_identifiers(self): return self.code.declared_identifiers.union(self.body_decl.allargnames) def undeclared_identifiers(self): return self.code.undeclared_identifiers.difference( self.code.declared_identifiers ) class CallNamespaceTag(Tag): def __init__(self, namespace, defname, attributes, **kwargs): super(CallNamespaceTag, self).__init__( namespace + ":" + defname, attributes, tuple(attributes.keys()) + ("args",), (), (), **kwargs ) self.expression = "%s.%s(%s)" % ( namespace, defname, ",".join( [ "%s=%s" % (k, v) for k, v in self.parsed_attributes.items() if k != "args" ] ), ) self.code = ast.PythonCode(self.expression, **self.exception_kwargs) self.body_decl = ast.FunctionArgs( attributes.get("args", ""), **self.exception_kwargs ) def declared_identifiers(self): return self.code.declared_identifiers.union(self.body_decl.allargnames) def undeclared_identifiers(self): return self.code.undeclared_identifiers.difference( self.code.declared_identifiers ) class InheritTag(Tag): __keyword__ = "inherit" def __init__(self, keyword, attributes, **kwargs): super(InheritTag, self).__init__( keyword, attributes, ("file",), (), ("file",), **kwargs ) class PageTag(Tag): __keyword__ = "page" def __init__(self, keyword, attributes, **kwargs): expressions = [ "cached", "args", "expression_filter", "enable_loop", ] + [c for c in attributes if c.startswith("cache_")] super(PageTag, self).__init__( keyword, attributes, expressions, (), (), **kwargs ) self.body_decl = ast.FunctionArgs( attributes.get("args", ""), **self.exception_kwargs ) self.filter_args = ast.ArgumentList( attributes.get("expression_filter", ""), **self.exception_kwargs ) def declared_identifiers(self): return self.body_decl.allargnames