Source code for kajiki.xml_template

import abc
import collections
import html
import io
import re
from codecs import open
from sys import version_info
from xml import sax
from xml.dom import minidom as dom
from xml.sax import SAXParseException

from kajiki import ir, template
from kajiki.doctype import DocumentTypeDeclaration, extract_dtd
from kajiki.html_utils import HTML_CDATA_TAGS, HTML_OPTIONAL_END_TAGS, HTML_REQUIRED_END_TAGS
from kajiki.markup_template import QDIRECTIVES, QDIRECTIVES_DICT

impl = dom.getDOMImplementation(" ")


def XMLTemplate(  # noqa: N802
    source=None,
    filename=None,
    mode=None,
    is_fragment=False,  # noqa: FBT002
    encoding="utf-8",
    autoblocks=None,
    cdata_scripts=True,  # noqa: FBT002
    strip_text=False,  # noqa: FBT002
    base_globals=None,
):
    """Given XML source code of a Kajiki Templates parses and returns
    a template class.

    The source code is parsed to its DOM representation by
    :class:`._Parser`, which is then expanded to separate directives
    from tags by :class:`._DomTransformer` and then compiled to the
    *Intermediate Representation* tree by :class:`._Compiler`.

    The *Intermediate Representation* generates the Python code
    which creates a new :class:`kajiki.template._Template` subclass
    through :meth:`kajiki.template.Template`.

    The generated code is then executed to return the newly created
    class.

    Calling ``.render()`` on an instance of the generate class will
    then render the template.
    """
    if source is None:
        with open(filename, encoding=encoding) as f:
            source = f.read()  # source is a unicode string
    if filename is None:
        filename = "<string>"
    doc = _Parser(filename, source).parse()
    doc = _DomTransformer(doc, strip_text=strip_text).transform()
    ir_ = _Compiler(
        filename,
        doc,
        mode=mode,
        is_fragment=is_fragment,
        autoblocks=autoblocks,
        cdata_scripts=cdata_scripts,
    ).compile()
    return template.from_ir(ir_, base_globals=base_globals)


def annotate(gen):
    def inner(self, node, *args, **kwargs):
        for x in gen(self, node, *args, **kwargs):
            self._anno(node, x)
            yield x

    return inner


[docs] class _Compiler: """Compiles a DOM tree into IR :class:`kajiki.ir.TemplateNode`. Intermediate Representation is a tree of nodes that represent Python Code that should be generated to execute the template. """ def __init__( self, filename, doc, mode=None, is_fragment=False, # noqa: FBT002 autoblocks=None, cdata_scripts=True, # noqa: FBT002 ): self.filename = filename self.doc = doc self.is_fragment = is_fragment self.functions = collections.defaultdict(list) self.functions["__main__()"] = [] self.function_lnos = {} self.mod_py = [] self.autoblocks = autoblocks or [] self.cdata_scripts = cdata_scripts self.in_def = False self.is_child = False # The rendering mode is either specified in the *mode* argument, # or inferred from the DTD: self._dtd = DocumentTypeDeclaration.matching(self.doc._dtd) # noqa: SLF001 if mode: self.mode = mode elif self._dtd: self.mode = self._dtd.rendering_mode else: # The template might contain an unknown DTD self.mode = "xml" # by default
[docs] def compile(self): """Compile the document provided by :class:`._Parser`. Returns as :class:`kajiki.ir.TemplateNode` instance representing the whole tree of nodes as their intermediate representation. The returned template will include at least a ``__main__`` function which is the document itself including a DOCTYPE and any function declared through ``py:def`` or as a ``py:block``. The ``TemplateNode`` will also include the module level code specified through ``<?py %``. If the compiled document didn't specify a DOCTYPE provides one at least for HTML5. .. note:: As this alters the functions and mode wide code registries of the compiler ``compile`` should never be called twice or might lead to unexpected results. """ templateNodes = [ # noqa: N806 n for n in self.doc.childNodes if not isinstance(n, dom.Comment) ] if len(templateNodes) != 1: msg = "expected a single root node in document" raise XMLTemplateCompileError(msg, self.doc, self.filename, 0) body = list(self._compile_node(templateNodes[0])) # Never emit doctypes on fragments if not self.is_fragment and not self.is_child: if self.doc._dtd: # noqa: SLF001 dtd = self.doc._dtd # noqa: SLF001 elif self.mode == "html5": dtd = "<!DOCTYPE html>" else: dtd = None if dtd: dtd = ir.TextNode(dtd.strip() + "\n") dtd.filename = self.filename dtd.lineno = 1 body.insert(0, dtd) self.functions["__main__()"] = body defs = [] for k, v in self.functions.items(): node = ir.DefNode(k, *v) node.lineno = self.function_lnos.get(k) defs.append(node) node = ir.TemplateNode(self.mod_py, defs) node.filename = self.filename node.lineno = 0 return node
def _anno(self, dom_node, ir_node): if ir_node.lineno: return ir_node.filename = self.filename ir_node.lineno = dom_node.lineno def _is_autoblock(self, node): if node.tagName not in self.autoblocks: return False if node.hasAttribute("py:autoblock"): guard = node.getAttribute("py:autoblock").lower() if guard not in ("false", "true"): msg = "py:autoblock is evaluated at compile time " "and only accepts True/False constants" raise ValueError(msg) if guard == "false": # We throw away the attribute so it doesn't remain in rendered nodes. node.removeAttribute("py:autoblock") return False return True def _compile_node(self, node): """Convert a DOM node to its intermediate representation. Calls specific compile functions for special nodes and any directive that was expanded by :meth:`._DomTransformer._expand_directives`. For any plain XML node forward it to :meth:`._compile_xml`. Automatically converts any ``autoblock`` node to a ``py:block`` directive. """ if isinstance(node, dom.Comment): return self._compile_comment(node) if isinstance(node, dom.Text): return self._compile_text(node) if isinstance(node, dom.ProcessingInstruction): return self._compile_pi(node) if self._is_autoblock(node): # Set the name of the block equal to the tag itself. node.setAttribute("name", node.tagName) return self._compile_block(node) if node.tagName.startswith("py:"): # Handle directives compiler = getattr(self, "_compile_{}".format(node.tagName.split(":")[-1]), self._compile_xml) return compiler(node) return self._compile_xml(node) @annotate def _compile_xml(self, node): """Compile plain XML nodes. When compiling a node also take care of directives that only modify the node itself (``py:strip``, ``py:attrs`` and ``py:content``) as all directives wrapping the node and its children have already been handled by :meth:`._compile_node`. The provided intermediate representations include the node itself, its attributes and its content. Attributes of the node are handled through :class:`._TextCompiler` to ensure ${expr} expressions are handled in attributes too. In case the node has children (and no py:content) compile the children too. """ content = attrs = guard = None if node.hasAttribute("py:strip"): guard = node.getAttribute("py:strip") if guard == "": # py:strip="" means yes, do strip the tag # noqa: SIM108 guard = "False" else: guard = f"not ({guard})" node.removeAttribute("py:strip") yield ir.TextNode(f"<{node.tagName}", guard) for k, v in sorted(node.attributes.items()): tc = _TextCompiler( self.filename, v, node.lineno, ir.TextNode, in_html_attr=True, compiler_instance=self, ) v = list(tc) # noqa: PLW2901 if k == "py:content": content = node.getAttribute("py:content") continue elif k == "py:attrs": attrs = node.getAttribute("py:attrs") continue yield ir.AttrNode(k, v, guard, self.mode) if attrs: yield ir.AttrsNode(attrs, guard, self.mode) if content: yield ir.TextNode(">", guard) yield ir.ExprNode(content) yield ir.TextNode(f"</{node.tagName}>", guard) elif node.childNodes: yield ir.TextNode(">", guard) if self.cdata_scripts and node.tagName in HTML_CDATA_TAGS: # Special behaviour for <script>, <style> tags: if self.mode == "xml": # Start escaping yield ir.TextNode("/*<![CDATA[*/") # Need to unescape the contents of these tags for child in node.childNodes: # CDATA for scripts and styles are automatically managed. if getattr(child, "_cdata", False): continue assert isinstance(child, dom.Text) # noqa: S101 for x in self._compile_text(child): if child.escaped: # If user declared CDATA no escaping happened. x.text = html.unescape(x.text) yield x if self.mode == "xml": # Finish escaping yield ir.TextNode("/*]]>*/") else: for cn in node.childNodes: # Keep CDATA sections around if declared by user if getattr(cn, "_cdata", False): yield ir.TextNode(cn.data) continue for x in self._compile_node(cn): yield x if not (self.mode.startswith("html") and node.tagName in HTML_OPTIONAL_END_TAGS): yield ir.TextNode(f"</{node.tagName}>", guard) elif node.tagName in HTML_REQUIRED_END_TAGS: yield ir.TextNode(f"></{node.tagName}>", guard) elif self.mode.startswith("html"): if node.tagName in HTML_OPTIONAL_END_TAGS: yield ir.TextNode(">", guard) else: yield ir.TextNode(f"></{node.tagName}>", guard) else: yield ir.TextNode("/>", guard) @annotate def _compile_replace(self, node): """Convert py:replace nodes to their intermediate representation.""" yield ir.ExprNode(node.getAttribute("value")) @annotate def _compile_pi(self, node): """Convert <?py and <?python nodes to their intermediate representation. Any code identified by :class:`.ir.PythonNode` as ``module_level`` (it starts with % character) will be registered in compiler registry of module wide code to be provided to be template. """ body = ir.TextNode(node.data.strip()) node = ir.PythonNode(body) if node.module_level: self.mod_py.append(node) else: yield node @annotate def _compile_import(self, node): """Convert py:import nodes to their intermediate representation.""" href = node.getAttribute("href") if node.hasAttribute("alias"): yield ir.ImportNode(href, node.getAttribute("alias")) else: yield ir.ImportNode(href) @annotate def _compile_extends(self, node): """Convert py:extends nodes to their intermediate representation.""" self.is_child = True href = node.getAttribute("href") yield ir.ExtendNode(href) yield from self._compile_nop(node) @annotate def _compile_include(self, node): """Convert py:include nodes to their intermediate representation.""" href = node.getAttribute("href") yield ir.IncludeNode(href) @annotate def _compile_block(self, node): """Convert py:block nodes to their intermediate representation. Any compiled block will be registered in the compiler functions registry to be provided to the template. """ fname = "_kj_block_" + node.getAttribute("name") decl = fname + "()" body = list(self._compile_nop(node)) if not body: body = [ir.PassNode()] self.functions[decl] = body if self.is_child: parent_block = "parent." + fname body.insert(0, ir.PythonNode(ir.TextNode(f"parent_block={parent_block}"))) else: yield ir.ExprNode(decl) @annotate def _compile_def(self, node): """Convert py:def nodes to their intermediate representation. Any compiled definition will be registered in the compiler functions registry to be provided to the template. """ old_in_def, self.in_def = self.in_def, True body = list(self._compile_nop(node)) self.in_def = old_in_def if self.in_def: yield ir.InnerDefNode(node.getAttribute("function"), *body) else: self.functions[node.getAttribute("function")] = body @annotate def _compile_call(self, node): """Convert py:call nodes to their intermediate representation.""" if node.childNodes[0].hasAttribute("args"): defn = "$caller(" + node.childNodes[0].getAttribute("args") + ")" else: defn = "$caller()" yield ir.CallNode(defn, node.getAttribute("function").replace("%caller", "$caller"), *self._compile_nop(node)) @annotate def _compile_text(self, node): """Compile text nodes to their intermediate representation""" kwargs = {} if node.parentNode and node.parentNode.tagName in HTML_CDATA_TAGS: # script and style should always be untranslatable. kwargs["node_type"] = ir.TextNode tc = _TextCompiler(self.filename, node.data, node.lineno, compiler_instance=self, **kwargs) yield from tc @annotate def _compile_comment(self, node): """Convert comments to their intermediate representation.""" if not node.data.startswith("!"): yield ir.TextNode(f"<!-- {node.data} -->") @annotate def _compile_for(self, node): """Convert py:for nodes to their intermediate representation.""" yield ir.ForNode(node.getAttribute("each"), *list(self._compile_nop(node))) @annotate def _compile_with(self, node): """Convert py:with nodes to their intermediate representation.""" yield ir.WithNode(node.getAttribute("vars"), *list(self._compile_nop(node))) @annotate def _compile_switch(self, node): """Convert py:switch nodes to their intermediate representation.""" body = [] # Filter out empty text nodes and report unsupported nodes for n in self._compile_nop(node): if isinstance(n, ir.TextNode) and not n.text.strip(): continue elif not isinstance(n, (ir.CaseNode, ir.ElseNode)): msg = "py:switch directive can only contain py:case and py:else nodes " "and cannot be placed on a tag." raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=node.lineno, ) body.append(n) yield ir.SwitchNode(node.getAttribute("test"), *body) @annotate def _compile_match(self, node): """Convert py:match nodes to their IR.""" if version_info < (3, 10): msg = "At least Python 3.10 is required to use the py:match directive" raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=node.lineno, ) body = [] # Filter out empty text nodes and report unsupported nodes for n in self._compile_nop(node): if isinstance(n, ir.TextNode) and not n.text.strip(): continue elif not isinstance(n, ir.MatchCaseNode): msg = "py:match directive can only contain py:case nodes and cannot be placed on a tag." raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=node.lineno, ) body.append(n) yield ir.MatchNode(node.getAttribute("on"), *body) @annotate def _compile_case(self, node): """Convert py:case nodes to their intermediate representation.""" if node.getAttribute("value"): yield ir.CaseNode(node.getAttribute("value"), *list(self._compile_nop(node))) elif node.getAttribute("match"): yield ir.MatchCaseNode(node.getAttribute("match"), *list(self._compile_nop(node))) else: msg = "case must have either value or match attribute, the former for py:switch, the latter for py:match" raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=node.lineno, ) @annotate def _compile_if(self, node): """Convert py:if nodes to their intermediate representation.""" yield ir.IfNode(node.getAttribute("test"), *list(self._compile_nop(node))) @annotate def _compile_else(self, node): """Convert py:else nodes to their intermediate representation.""" if ( getattr(node.parentNode, "tagName", "") != "py:nop" and not node.parentNode.hasAttribute("py:switch") and getattr(node.previousSibling, "tagName", "") != "py:if" ): msg = ( "py:else directive must be inside a py:switch or directly after py:if " "without text or spaces in between" ) raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=node.lineno, ) yield ir.ElseNode(*list(self._compile_nop(node))) @annotate def _compile_nop(self, node): for c in node.childNodes: yield from self._compile_node(c)
def make_text_node(text, guard=None): """Return a TranslatableTextNode if the text is not empty, otherwise a regular TextNode. This avoid spending the cost of translating empty nodes. """ if text.strip(): return ir.TranslatableTextNode(text, guard) return ir.TextNode(text, guard) class _TextCompiler: """Separates expressions such as ${some_var} from the ordinary text around them in the template source and generates :class:`.ir.ExprNode` instances and :class:`.ir.TextNode` instances accordingly. """ def __init__( self, filename, source, lineno, node_type=make_text_node, in_html_attr=False, # noqa: FBT002 compiler_instance=None, ): self.filename = filename self.source = source self.orig_lineno = lineno self.lineno = 0 self.pos = 0 self.node_type = node_type self.in_html_attr = in_html_attr self.compiler_instance = compiler_instance self.doc = self.compiler_instance.doc def text(self, text): node = self.node_type(text) node.lineno = self.real_lineno self.lineno += text.count("\n") return node def expr(self, text): # *safe* being True here avoids escaping twice, since # HTML attributes are always escaped in the end. node = ir.ExprNode(text, safe=self.in_html_attr) node.lineno = self.real_lineno self.lineno += text.count("\n") return node @property def real_lineno(self): return self.orig_lineno + self.lineno _pattern = r""" \$(?: (?P<expr_named>[_a-z][_a-z0-9.]*) | # $foo.bar {(?P<expr_braced>) | # ${.... \$ # $$ -> $ )""" _re_pattern = re.compile(_pattern, re.VERBOSE | re.IGNORECASE | re.MULTILINE) def __iter__(self): source = self.source for mo in self._re_pattern.finditer(source): start = mo.start() if start > self.pos: yield self.text(source[self.pos : start]) self.pos = start groups = mo.groupdict() if groups["expr_braced"] is not None: self.pos = mo.end() yield self._get_braced_expr() elif groups["expr_named"] is not None: self.pos = mo.end() yield self.expr(groups["expr_named"]) else: # handle $$ and $ followed by anything that is neither a valid # variable name or braced expression self.pos = mo.end() yield self.text("$") if self.pos != len(source): yield self.text(source[self.pos :]) def _get_braced_expr(self): # see https://github.com/nandoflorestan/kajiki/pull/38 # Trying to get the position of a closing } in braced expressions # So, self.source can be something like `1+1=${1+1} ahah` # in this case this function gets called only once with # self.pos equal to 6 this function must return the result of # self.expr('1+1') and must set self.pos to 9 def py_expr(end=None): return self.source[self.pos : end] try: self.pos += len(py_expr()) - len(py_expr().lstrip()) compile(py_expr(), "find_}", "eval") except SyntaxError as se: end = sum( [self.pos, se.offset] + [len(line) + 1 for idx, line in enumerate(py_expr().splitlines()) if idx < se.lineno - 1] ) if py_expr(end)[-1] != "}": # for example unclosed strings msg = f"Kajiki can't compile the python expression `{py_expr()[:-1]}`" raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=self.lineno, ) from None # if the expression ends in a } then it may be valid try: compile(py_expr(end - 1), "check_validity", "eval") except SyntaxError: # for example + operators with a single operand msg = f"Kajiki detected an invalid python expression `{py_expr()[:-1]}`" raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=self.lineno, ) from None py_text = py_expr(end - 1) self.pos = end return self.expr(py_text) else: msg = "Braced expression not terminated" raise XMLTemplateCompileError( msg, doc=self.doc, filename=self.filename, linen=self.lineno, )
[docs] class _Parser(sax.ContentHandler): """Parse an XML template into a Tree of DOM Nodes. Nodes should then be passed to a `_Compiler` to be converted into the intermediate representation and then to Python Code. """ DTD = '<!DOCTYPE kajiki SYSTEM "kajiki.dtd">' def __init__(self, filename, source): """XML defines only a few entities; HTML defines many more. The XML parser errors out when it finds HTML entities, unless the template contains a reference to an external DTD (in which case skippedEntity() gets called, this is what we want). In other words, we want to trick expat into parsing XML + HTML entities for us. We wouldn't force our users to declare everyday HTML entities! So, for the parsing stage, we detect the doctype in the template and replace it with our own; then in the compiling stage we put the user's doctype back in. The XML parser is thus tricked and nobody needs to know this implementation detail of Kajiki. """ sax.ContentHandler.__init__(self) if not isinstance(source, str): msg = "The template source must be a unicode string." raise TypeError(msg) self._els = [] self._doc = dom.Document() self._filename = filename # Store the original DTD in the document for the compiler to use later self._doc._dtd, position, source = extract_dtd(source) # noqa: SLF001 # Use our own DTD just for XML parsing self._source = source[:position] + self.DTD + source[position:] self._cdata_stack = []
[docs] def parse(self): """Parse an XML/HTML document to its DOM representation.""" self._parser = parser = sax.make_parser() # noqa: S317 parser.setFeature(sax.handler.feature_external_pes, False) parser.setFeature(sax.handler.feature_external_ges, False) parser.setFeature(sax.handler.feature_namespaces, False) parser.setProperty(sax.handler.property_lexical_handler, self) parser.setContentHandler(self) source = sax.xmlreader.InputSource() source.setCharacterStream(io.StringIO(self._source)) source.setSystemId(self._filename) try: parser.parse(source) except SAXParseException as e: raise XMLTemplateParseError( e.getMessage(), self._source, self._filename, e.getLineNumber(), e.getColumnNumber(), ) from None self._doc._source = self._source # noqa: SLF001 return self._doc
# ContentHandler implementation
[docs] def startDocument(self): # noqa: N802 self._els.append(self._doc)
[docs] def startElement(self, name, attrs): # noqa: N802 el = self._doc.createElement(name) el.lineno = self._parser.getLineNumber() for k, v in attrs.items(): el.setAttribute(k, v) self._els[-1].appendChild(el) self._els.append(el)
[docs] def endElement(self, name): # noqa: N802 popped = self._els.pop() assert name == popped.tagName # noqa: S101
[docs] def characters(self, content): should_escape = not self._cdata_stack if should_escape: content = sax.saxutils.escape(content) node = self._doc.createTextNode(content) node.lineno = self._parser.getLineNumber() node.escaped = should_escape self._els[-1].appendChild(node)
[docs] def processingInstruction(self, target, data): # noqa: N802 node = self._doc.createProcessingInstruction(target, data) node.lineno = self._parser.getLineNumber() self._els[-1].appendChild(node)
[docs] def skippedEntity(self, name): # noqa: N802 # Deals with an HTML entity such as &nbsp; (XML itself defines # very few entities.) # The presence of a SYSTEM doctype makes expat say "hey, that # MIGHT be a valid entity, better pass it along to sax and # find out!" (Since expat is nonvalidating, it never reads the # external doctypes.) if name and name[-1] != ";": # In entities.html5 sometimes the entities are recorded # with/without semicolon. That list is copied from cPython # itself, and we don't want to maintain a separate diff. # So just ensure we ask for entities always recorded with # trailing semicolon. name += ";" return self.characters(html.entities.html5[name])
[docs] @abc.abstractmethod def startElementNS(self, name, qname, attrs): # noqa: N802 pass
[docs] @abc.abstractmethod def endElementNS(self, name, qname): # noqa: N802 pass
[docs] @abc.abstractmethod def startPrefixMapping(self, prefix, uri): # noqa: N802 pass
[docs] @abc.abstractmethod def endPrefixMapping(self, prefix): # noqa: N802 pass
# LexicalHandler implementation def comment(self, text): node = self._doc.createComment(text) node.lineno = self._parser.getLineNumber() self._els[-1].appendChild(node) def startCDATA(self): # noqa: N802 node = self._doc.createTextNode("<![CDATA[") node._cdata = True # noqa: SLF001 node.lineno = self._parser.getLineNumber() self._els[-1].appendChild(node) self._cdata_stack.append(self._els[-1]) def endCDATA(self): # noqa: N802 node = self._doc.createTextNode("]]>") node._cdata = True # noqa: SLF001 node.lineno = self._parser.getLineNumber() self._els[-1].appendChild(node) self._cdata_stack.pop() def startDTD(self, name, pubid, sysid): # noqa: N802 self._doc.doctype = impl.createDocumentType(name, pubid, sysid) def endDTD(self): # noqa: N802 pass
[docs] class _DomTransformer: """Applies standard Kajiki transformations to a parsed document. Given a document generated by :class:`.Parser` it applies some node transformations that are necessary before applying the compilation steps to achieve result we usually expect. This includes things like squashing consecutive text nodes and expanding ``py:`` directives. The Transformer mutates the original document. """ def __init__(self, doc, strip_text=True): # noqa: FBT002 self._transformed = False self.doc = doc self._strip_text = strip_text
[docs] def transform(self): """Applies all the DOM transformations to the document. Calling this twice will do nothing as the result is persisted. """ if self._transformed: return self.doc self.doc = self._expand_directives(self.doc) self.doc = self._merge_text_nodes(self.doc) self.doc = self._extract_nodes_leading_and_trailing_spaces(self.doc) if self._strip_text: self.doc = self._strip_text_nodes(self.doc) return self.doc
@classmethod def _merge_text_nodes(cls, tree): """Merges consecutive TextNodes into a single TextNode. Nodes are replaced with a new node whose data contains the concatenation of all replaced nodes data. Any other node (including CDATA TextNodes) splits runs of TextNodes. """ if isinstance(tree, dom.Document): cls._merge_text_nodes(tree.firstChild) return tree if not isinstance(getattr(tree, "tagName", None), str): return tree # Squash all successive text nodes into a single one. merge_node = None for child in list(tree.childNodes): if isinstance(child, dom.Text) and not getattr(child, "_cdata", False): if merge_node is None: merge_node = child.ownerDocument.createTextNode(child.data) merge_node.lineno = child.lineno merge_node.escaped = child.escaped tree.replaceChild(newChild=merge_node, oldChild=child) else: merge_node.data = merge_node.data + child.data tree.removeChild(child) else: merge_node = None # Apply squashing to all children of current node. for child in tree.childNodes: if not isinstance(child, dom.Text): cls._merge_text_nodes(child) return tree @classmethod def _extract_nodes_leading_and_trailing_spaces(cls, tree): """Extract the leading and trailing spaces of TextNodes to separate nodes. This is explicitly intended to make i18n easier, as we don't want people having to pay attention to spaces at being and end of text when translating it. So those are always extracted and only the meaningful part is preserved for translation. """ for child in tree.childNodes: if isinstance(child, dom.Text): if not getattr(child, "_cdata", False): if not child.data.strip(): # Already a totally empty node, do nothing... continue lstripped_data = child.data.lstrip() if len(lstripped_data) != len(child.data): # There is text to strip at begin, create a # new text node with empty space empty_text_len = len(child.data) - len(lstripped_data) empty_text = child.data[:empty_text_len] begin_node = child.ownerDocument.createTextNode(empty_text) begin_node.lineno = child.lineno begin_node.escaped = child.escaped tree.insertBefore(newChild=begin_node, refChild=child) child.lineno += child.data[:empty_text_len].count("\n") child.data = lstripped_data rstripped_data = child.data.rstrip() if len(rstripped_data) != len(child.data): # There is text to strip at end, create a new # text node with empty space empty_text_len = len(child.data) - len(rstripped_data) empty_text = child.data[-empty_text_len:] end_node = child.ownerDocument.createTextNode(empty_text) end_node.lineno = child.lineno + child.data[:-empty_text_len].count("\n") end_node.escaped = child.escaped tree.replaceChild(newChild=end_node, oldChild=child) tree.insertBefore(newChild=child, refChild=end_node) child.data = rstripped_data else: cls._extract_nodes_leading_and_trailing_spaces(child) return tree @classmethod def _strip_text_nodes(cls, tree): """Strips empty characters in all text nodes.""" for child in tree.childNodes: if isinstance(child, dom.Text): if not getattr(child, "_cdata", False): # Move lineno forward the amount of lines we are # going to strip. lstripped_data = child.data.lstrip() child.lineno += child.data[: len(child.data) - len(lstripped_data)].count("\n") child.data = child.data.strip() else: cls._strip_text_nodes(child) return tree @classmethod def _expand_directives(cls, tree, parent=None): """Expands directives attached to nodes into separate nodes. This will convert all instances of:: <div py:if="check"> </div> into:: <py:if test="check"> <div> </div> </py:if> This ensures that whenever a template is processed there is no difference between the two formats as the Compiler will always receive the latter. """ if isinstance(tree, dom.Document): cls._expand_directives(tree.firstChild, tree) return tree if not isinstance(getattr(tree, "tagName", None), str): return tree if tree.tagName in QDIRECTIVES_DICT: attrs = QDIRECTIVES_DICT[tree.tagName] if not isinstance(attrs, tuple): attrs = [attrs] for attr in attrs: tree.setAttribute(tree.tagName, tree.getAttribute(attr)) tree.tagName = "py:nop" if tree.tagName != "py:nop" and tree.hasAttribute("py:extends"): value = tree.getAttribute("py:extends") el = tree.ownerDocument.createElement("py:extends") el.setAttribute("href", value) el.lineno = tree.lineno tree.removeAttribute("py:extends") tree.childNodes.insert(0, el) for directive, attr in QDIRECTIVES: if not tree.hasAttribute(directive): continue value = tree.getAttribute(directive) tree.removeAttribute(directive) # nsmap = (parent is not None) and parent.nsmap or tree.nsmap el = tree.ownerDocument.createElement(directive) el.lineno = tree.lineno if isinstance(attr, tuple): # eg: handle bare py:case tags for at in attr: el.setAttribute(at, dict(tree.attributes.items()).get(at)) if directive == "py:case" and tree.nodeName != "py:case": if tree.parentNode.nodeName == "py:match" or "py:match" in tree.parentNode.attributes: at = "on" else: at = "value" el.setAttribute(at, value) elif attr: el.setAttribute(attr, value) # el.setsourceline = tree.sourceline parent.replaceChild(newChild=el, oldChild=tree) el.appendChild(tree) cls._expand_directives(tree, el) return el for child in tree.childNodes: cls._expand_directives(child, tree) return tree
class XMLTemplateError(template.KajikiTemplateError): """Base class for all Parse/Compile errors.""" class XMLTemplateCompileError(XMLTemplateError): """Error for failed template constraints. This is used to signal directives in contexts where they are invalid or any kajiki template constraint that fails in the provided template code. """ def __init__(self, msg, doc, filename, linen): super().__init__(msg, getattr(doc, "_source", ""), filename, linen, 0) class XMLTemplateParseError(XMLTemplateError): """Error while parsing template XML. Signals an invalid XML error in the provided template code. """