Mercurial > genshi > mirror
view markup/output.py @ 47:486d975cc24b trunk
fix CSS classes for Trac about.html ctxtnav
author | mgood |
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date | Tue, 04 Jul 2006 03:25:27 +0000 |
parents | b4f78c05e5c9 |
children | 59eb24184e9c |
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# -*- coding: utf-8 -*- # # Copyright (C) 2006 Christopher Lenz # All rights reserved. # # This software is licensed as described in the file COPYING, which # you should have received as part of this distribution. The terms # are also available at http://markup.cmlenz.net/wiki/License. # # This software consists of voluntary contributions made by many # individuals. For the exact contribution history, see the revision # history and logs, available at http://markup.cmlenz.net/log/. """This module provides different kinds of serialization methods for XML event streams. """ try: frozenset except NameError: from sets import ImmutableSet as frozenset from markup.core import Markup, Namespace, QName, Stream __all__ = ['Serializer', 'XMLSerializer', 'HTMLSerializer'] class Serializer(object): """Base class for serializers.""" def serialize(self, stream): """Must be implemented by concrete subclasses to serialize the given stream. This method must be implemented as a generator, producing the serialized output incrementally as unicode strings. """ raise NotImplementedError class XMLSerializer(Serializer): """Produces XML text from an event stream. >>> from markup.builder import tag >>> elem = tag.div(tag.a(href='foo'), tag.br, tag.hr(noshade=True)) >>> print ''.join(XMLSerializer().serialize(elem.generate())) <div><a href="foo"/><br/><hr noshade="True"/></div> """ def serialize(self, stream): ns_attrib = [] ns_mapping = {} stream = _PushbackIterator(stream) for kind, data, pos in stream: if kind is Stream.DOCTYPE: # FIXME: what if there's no system or public ID in the input? yield Markup('<!DOCTYPE %s "%s" "%s">\n' % data) elif kind is Stream.START_NS: prefix, uri = data if uri not in ns_mapping: ns_mapping[uri] = prefix if not prefix: ns_attrib.append((QName('xmlns'), uri)) else: ns_attrib.append((QName('xmlns:%s' % prefix), uri)) elif kind is Stream.START: tag, attrib = data tagname = tag.localname if tag.namespace: try: prefix = ns_mapping[tag.namespace] if prefix: tagname = prefix + ':' + tag.localname except KeyError: ns_attrib.append((QName('xmlns'), tag.namespace)) buf = ['<', tagname] if ns_attrib: attrib.extend(ns_attrib) ns_attrib = [] for attr, value in attrib: attrname = attr.localname if attr.namespace: prefix = ns_mapping.get(attr.namespace) if prefix: attrname = prefix + ':' + attrname buf.append(' %s="%s"' % (attrname, Markup.escape(value))) kind, data, pos = stream.next() if kind is Stream.END: buf.append('/>') else: buf.append('>') stream.pushback((kind, data, pos)) yield Markup(''.join(buf)) elif kind is Stream.END: tag = data tagname = tag.localname if tag.namespace: prefix = ns_mapping.get(tag.namespace) if prefix: tagname = prefix + ':' + tag.localname yield Markup('</%s>' % tagname) elif kind is Stream.TEXT: yield Markup.escape(data, quotes=False) class HTMLSerializer(Serializer): """Produces HTML text from an event stream. >>> from markup.builder import tag >>> elem = tag.div(tag.a(href='foo'), tag.br, tag.hr(noshade=True)) >>> print ''.join(HTMLSerializer().serialize(elem.generate())) <div><a href="foo"></a><br><hr noshade></div> """ NAMESPACE = Namespace('http://www.w3.org/1999/xhtml') _EMPTY_ELEMS = frozenset(['area', 'base', 'basefont', 'br', 'col', 'frame', 'hr', 'img', 'input', 'isindex', 'link', 'meta', 'param']) _BOOLEAN_ATTRS = frozenset(['selected', 'checked', 'compact', 'declare', 'defer', 'disabled', 'ismap', 'multiple', 'nohref', 'noresize', 'noshade', 'nowrap']) def serialize(self, stream): ns_mapping = {} stream = _PushbackIterator(stream) for kind, data, pos in stream: if kind is Stream.DOCTYPE: yield Markup('<!DOCTYPE %s "%s" "%s">\n' % data) elif kind is Stream.START_NS: prefix, uri = data if uri not in ns_mapping: ns_mapping[uri] = prefix elif kind is Stream.START: tag, attrib = data if tag.namespace and tag not in self.NAMESPACE: continue # not in the HTML namespace, so don't emit buf = ['<', tag.localname] for attr, value in attrib: if attr.namespace and attr not in self.NAMESPACE: continue # not in the HTML namespace, so don't emit if attr.localname in self._BOOLEAN_ATTRS: if value: buf.append(' %s' % attr.localname) else: buf.append(' %s="%s"' % (attr.localname, Markup.escape(value))) if tag.localname in self._EMPTY_ELEMS: kind, data, pos = stream.next() if kind is not Stream.END: stream.pushback((kind, data, pos)) yield Markup(''.join(buf + ['>'])) elif kind is Stream.END: tag = data if tag.namespace and tag not in self.NAMESPACE: continue # not in the HTML namespace, so don't emit yield Markup('</%s>' % tag.localname) elif kind is Stream.TEXT: yield Markup.escape(data, quotes=False) class _PushbackIterator(object): """A simple wrapper for iterators that allows pushing items back on the queue via the `pushback()` method. That can effectively be used to peek at the next item.""" __slots__ = ['iterable', 'buf'] def __init__(self, iterable): self.iterable = iter(iterable) self.buf = [] def __iter__(self): return self def next(self): if self.buf: return self.buf.pop(0) return self.iterable.next() def pushback(self, item): self.buf.append(item)