1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189
|
"""
Kind of like htmlgen, only much simpler. The only important symbol
that is exported is ``html``.
This builds ElementTree nodes, but with some extra useful methods.
(Open issue: should it use ``ElementTree`` more, and the raw
``Element`` stuff less?)
You create tags with attribute access. I.e., the ``A`` anchor tag is
``html.a``. The attributes of the HTML tag are done with keyword
arguments. The contents of the tag are the non-keyword arguments
(concatenated). You can also use the special ``c`` keyword, passing a
list, tuple, or single tag, and it will make up the contents (this is
useful because keywords have to come after all non-keyword arguments,
which is non-intuitive). Or you can chain them, adding the keywords
with one call, then the body with a second call, like::
>>> print html.a(href='http://yahoo.com')('<Yahoo>')
<a href=\"http://yahoo.com\"><Yahoo></a>
Note that strings will be quoted; only tags given explicitly will
remain unquoted.
If the value of an attribute is None, then no attribute
will be inserted. So::
>>> print html.a(href='http://www.yahoo.com', name=None,
... c='Click Here')
<a href=\"http://www.yahoo.com\">Click Here</a>
If the value is None, then the empty string is used. Otherwise str()
is called on the value.
``html`` can also be called, and it will produce a special list from
its arguments, which adds a ``__str__`` method that does ``html.str``
(which handles quoting, flattening these lists recursively, and using
'' for ``None``).
``html.comment`` will generate an HTML comment, like
``html.comment('comment text')`` -- note that it cannot take keyword
arguments (because they wouldn't mean anything).
Examples::
>>> print html.html(
... html.head(html.title(\"Page Title\")),
... html.body(
... bgcolor='#000066',
... text='#ffffff',
... c=[html.h1('Page Title'),
... html.p('Hello world!')],
... ))
<html><head><title>Page Title</title></head><body bgcolor=\"#000066\" text=\"#ffffff\"><h1>Page Title</h1><p>Hello world!</p></body></html>
>>> print html.a(href='#top')('return to top')
<a href=\"#top\">return to top</a>
"""
from __future__ import generators
from cgi import escape
try:
import xml.etree.ElementTree as ET
except ImportError:
import elementtree.ElementTree as ET
default_encoding = 'utf-8'
class _HTML:
def __getattr__(self, attr):
if attr.startswith('_'):
raise AttributeError
attr = attr.lower()
if attr.endswith('_'):
attr = attr[:-1]
if attr.find('__') != -1:
attr = attr.replace('__', ':')
if attr == 'comment':
return Element(ET.Comment, {})
else:
return Element(attr, {})
def __call__(self, *args):
return ElementList(args)
def quote(self, arg):
if arg is None:
return ''
return escape(unicode(arg).encode(default_encoding), 1)
def str(self, arg, encoding=None):
if isinstance(arg, str):
return arg
elif arg is None:
return ''
elif isinstance(arg, unicode):
return arg.encode(default_encoding)
elif isinstance(arg, (list, tuple)):
return ''.join(map(self.str, arg))
elif isinstance(arg, Element):
return str(arg)
else:
return unicode(arg).encode(default_encoding)
html = _HTML()
class Element(ET._ElementInterface):
def __call__(self, *args, **kw):
el = self.__class__(self.tag, self.attrib)
if kw.has_key('c'):
if args:
raise ValueError(
"You may either provide positional arguments or a "
"'c' keyword argument, but not both")
args = kw['c']
del kw['c']
if not isinstance(args, (list, tuple)):
args = (args,)
for name, value in kw.items():
if value is None:
del kw[name]
continue
kw[name] = unicode(value)
if name.endswith('_'):
kw[name[:-1]] = value
del kw[name]
if name.find('__') != -1:
new_name = name.replace('__', ':')
kw[new_name] = value
del kw[name]
el.attrib.update(kw)
el.text = self.text
last = None
for item in self.getchildren():
last = item
el.append(item)
for arg in flatten(args):
if arg is None:
continue
if not ET.iselement(arg):
if last is None:
if el.text is None:
el.text = unicode(arg)
else:
el.text += unicode(arg)
else:
if last.tail is None:
last.tail = unicode(arg)
else:
last.tail += unicode(arg)
else:
last = arg
el.append(last)
return el
def __str__(self):
return ET.tostring(self, default_encoding)
def __unicode__(self):
# This is lame!
return str(self).decode(default_encoding)
def __repr__(self):
content = str(self)
if len(content) > 25:
content = repr(content[:25]) + '...'
else:
content = repr(content)
return '<Element %r>' % content
class ElementList(list):
def __str__(self):
return html.str(self)
def __repr__(self):
return 'ElementList(%s)' % list.__repr__(self)
def flatten(items):
for item in items:
if isinstance(item, (list, tuple)):
for sub in flatten(item):
yield sub
else:
yield item
__all__ = ['html']
|