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A simple way to generate valid xhtml in Python (circa 2007)
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| r"""Implementation of a `stan`_\ -like XML description language. | |
| .. _stan: http://www.kieranholland.com/code/documentation/nevow-stan/ | |
| An example XHTML page can be generated by: | |
| .. python:: | |
| def items(): | |
| return [ T.li['foo'], T.li['bar'], T.li['baz'] ] | |
| def adjective(): | |
| return "cruel" | |
| doc = T.html(class_="foo")[ # class is a keyword | |
| T.body[ | |
| T.p(id="123")[ # another tag attribute | |
| "Hello, world" # a string is an element | |
| ], | |
| T.br, # in [braces] put any sub-element | |
| T.a(href="#")[ | |
| "<Goodbye>, ", # special chars are escaped | |
| T.b[ adjective ], # callables can be sub-element | |
| " world", | |
| ], | |
| T.ul[ items ], # they can return element iterables too | |
| ] | |
| ] | |
| print toxhtml(doc) | |
| :copyright: 2007-2020 Daniele Varrazzo | |
| :contact: [email protected] | |
| """ | |
| import xml.etree.cElementTree as et | |
| class XmlTagFactory(object): | |
| """Return a `Tag` for each attribute read.""" | |
| def __getattr__(self, name): | |
| return Tag(name) | |
| T = XmlTagFactory() | |
| """The public `XmlTagFactory` instance.""" | |
| class Tag(object): | |
| """An XML tag description. | |
| - Use the ``()`` syntax to update tag attribute. | |
| - Use the ``[]`` syntax to add children elements. | |
| See the `ministan` module docstring for an example. | |
| """ | |
| def __init__(self, tag): | |
| """Return a new `Tag` instance.""" | |
| self.tag = tag | |
| self.children = [] | |
| self.attrs = {} | |
| def __call__(self, **kwargs): | |
| """Update the tag attributes.""" | |
| if "class_" in kwargs: | |
| kwargs["class"] = kwargs.pop("class_") | |
| for k, v in kwargs.items(): | |
| if v is None: | |
| continue | |
| if not isinstance(v, str): | |
| v = str(v) | |
| self.attrs[k] = v | |
| return self | |
| def __getitem__(self, idx): | |
| """Extend element children.""" | |
| if isinstance(idx, tuple): | |
| self.children.extend(idx) | |
| else: | |
| self.children.append(idx) | |
| return self | |
| def toelement(self): | |
| """Return an XML representation of the element with subelements. | |
| :rtype: ``ElementTree.Element`` | |
| """ | |
| builder = et.TreeBuilder() | |
| self._toelement(builder) | |
| return builder.close() | |
| def _toelement(self, builder): | |
| builder.start(self.tag, self.attrs) | |
| self._toelement_ch(builder, self.children) | |
| builder.end(self.tag) | |
| def _toelement_ch(self, builder, elem): | |
| if elem is None: | |
| return | |
| elif isinstance(elem, Tag): | |
| elem._toelement(builder) | |
| elif isinstance(elem, str): | |
| builder.data(elem) | |
| elif callable(elem): | |
| self._toelement_ch(builder, elem()) | |
| elif hasattr(elem, "__iter__"): # iterable | |
| for child in elem: | |
| self._toelement_ch(builder, child) | |
| else: | |
| builder.data(str(elem)) | |
| xhtml_trans_doctype = ( | |
| '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ' | |
| '"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">\n' | |
| ) | |
| """Transitional XHTML doctype.""" | |
| def toxhtml(tag): | |
| """Return the XHTML document represented by a `tag`. | |
| No assumption is done whether `tag` represents a valid XHTML document. | |
| :Parameters: | |
| `tag` : `Tag` | |
| the element to represent | |
| :return: the XHTML representation | |
| :rtype: `str` | |
| """ | |
| doc = tag.toelement() | |
| return xhtml_trans_doctype + et.tostring(doc) |
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