# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
"""
This module implements a class for handling URLs.
"""
import urllib
import cgi
from paste import request
# Imported lazily from FormEncode:
variabledecode = None
__all__ = ["URL", "Image"]
def html_quote(v):
if v is None:
return ''
return cgi.escape(str(v), 1)
def url_quote(v):
if v is None:
return ''
return urllib.quote(str(v))
url_unquote = urllib.unquote
def js_repr(v):
if v is None:
return 'null'
elif v is False:
return 'false'
elif v is True:
return 'true'
elif isinstance(v, list):
return '[%s]' % ', '.join(map(js_repr, v))
elif isinstance(v, dict):
return '{%s}' % ', '.join(
['%s: %s' % (js_repr(key), js_repr(value))
for key, value in v])
elif isinstance(v, str):
return repr(v)
elif isinstance(v, unicode):
# @@: how do you do Unicode literals in Javascript?
return repr(v.encode('UTF-8'))
elif isinstance(v, (float, int)):
return repr(v)
elif isinstance(v, long):
return repr(v).lstrip('L')
elif hasattr(v, '__js_repr__'):
return v.__js_repr__()
else:
raise ValueError(
"I don't know how to turn %r into a Javascript representation"
% v)
class URLResource(object):
"""
This is an abstract superclass for different kinds of URLs
"""
default_params = {}
def __init__(self, url, vars=None, attrs=None,
params=None):
self.url = url or '/'
self.vars = vars or []
self.attrs = attrs or {}
self.params = self.default_params.copy()
self.original_params = params or {}
if params:
self.params.update(params)
#@classmethod
def from_environ(cls, environ, with_query_string=True,
with_path_info=True, script_name=None,
path_info=None, querystring=None):
url = request.construct_url(
environ, with_query_string=False,
with_path_info=with_path_info, script_name=script_name,
path_info=path_info)
if with_query_string:
if querystring is None:
vars = request.parse_querystring(environ)
else:
vars = cgi.parse_qsl(
querystring,
keep_blank_values=True,
strict_parsing=False)
else:
vars = None
v = cls(url, vars=vars)
return v
from_environ = classmethod(from_environ)
def __call__(self, *args, **kw):
res = self._add_positional(args)
res = res._add_vars(kw)
return res
def __getitem__(self, item):
if '=' in item:
name, value = item.split('=', 1)
return self._add_vars({url_unquote(name): url_unquote(value)})
return self._add_positional((item,))
def attr(self, **kw):
for key in kw.keys():
if key.endswith('_'):
kw[key[:-1]] = kw[key]
del kw[key]
new_attrs = self.attrs.copy()
new_attrs.update(kw)
return self.__class__(self.url, vars=self.vars,
attrs=new_attrs,
params=self.original_params)
def param(self, **kw):
new_params = self.original_params.copy()
new_params.update(kw)
return self.__class__(self.url, vars=self.vars,
attrs=self.attrs,
params=new_params)
def coerce_vars(self, vars):
global variabledecode
need_variable_encode = False
for key, value in vars.items():
if isinstance(value, dict):
need_variable_encode = True
if key.endswith('_'):
vars[key[:-1]] = vars[key]
del vars[key]
if need_variable_encode:
if variabledecode is None:
from formencode import variabledecode
vars = variabledecode.variable_encode(vars)
return vars
def var(self, **kw):
kw = self.coerce_vars(kw)
new_vars = self.vars + kw.items()
return self.__class__(self.url, vars=new_vars,
attrs=self.attrs,
params=self.original_params)
def setvar(self, **kw):
"""
Like ``.var(...)``, except overwrites keys, where .var simply
extends the keys. Setting a variable to None here will
effectively delete it.
"""
kw = self.coerce_vars(kw)
new_vars = []
for name, values in self.vars:
if name in kw:
continue
new_vars.append((name, values))
new_vars.extend(kw.items())
return self.__class__(self.url, vars=new_vars,
attrs=self.attrs,
params=self.original_params)
def setvars(self, **kw):
"""
Creates a copy of this URL, but with all the variables set/reset
(like .setvar(), except clears past variables at the same time)
"""
return self.__class__(self.url, vars=kw.items(),
attrs=self.attrs,
params=self.original_params)
def addpath(self, *paths):
u = self
for path in paths:
path = str(path).lstrip('/')
new_url = u.url
if not new_url.endswith('/'):
new_url += '/'
u = u.__class__(new_url+path, vars=u.vars,
attrs=u.attrs,
params=u.original_params)
return u
__div__ = addpath
def become(self, OtherClass):
return OtherClass(self.url, vars=self.vars,
attrs=self.attrs,
params=self.original_params)
def href__get(self):
s = self.url
if self.vars:
s += '?'
vars = []
for name, val in self.vars:
if isinstance(val, (list, tuple)):
val = [v for v in val if v is not None]
elif val is None:
continue
vars.append((name, val))
s += urllib.urlencode(vars, True)
return s
href = property(href__get)
def __repr__(self):
base = '<%s %s' % (self.__class__.__name__,
self.href or "''")
if self.attrs:
base += ' attrs(%s)' % (
' '.join(['%s="%s"' % (html_quote(n), html_quote(v))
for n, v in self.attrs.items()]))
if self.original_params:
base += ' params(%s)' % (
', '.join(['%s=%r' % (n, v)
for n, v in self.attrs.items()]))
return base + '>'
def html__get(self):
if not self.params.get('tag'):
raise ValueError(
"You cannot get the HTML of %r until you set the "
"'tag' param'" % self)
content = self._get_content()
tag = '<%s' % self.params.get('tag')
attrs = ' '.join([
'%s="%s"' % (html_quote(n), html_quote(v))
for n, v in self._html_attrs()])
if attrs:
tag += ' ' + attrs
tag += self._html_extra()
if content is None:
return tag + ' />'
else:
return '%s>%s</%s>' % (tag, content, self.params.get('tag'))
html = property(html__get)
def _html_attrs(self):
return self.attrs.items()
def _html_extra(self):
return ''
def _get_content(self):
"""
Return the content for a tag (for self.html); return None
for an empty tag (like ``<img />``)
"""
raise NotImplementedError
def _add_vars(self, vars):
raise NotImplementedError
def _add_positional(self, args):
raise NotImplementedError
class URL(URLResource):
r"""
>>> u = URL('http://localhost')
>>> u
<URL http://localhost>
>>> u = u['view']
>>> str(u)
'http://localhost/view'
>>> u['//foo'].param(content='view').html
'<a href="http://localhost/view/foo">view</a>'
>>> u.param(confirm='Really?', content='goto').html
'<a href="http://localhost/view" onclick="return confirm(\'Really?\')">goto</a>'
>>> u(title='See "it"', content='goto').html
'<a href="http://localhost/view?title=See+%22it%22">goto</a>'
>>> u('another', var='fuggetaboutit', content='goto').html
'<a href="http://localhost/view/another?var=fuggetaboutit">goto</a>'
>>> u.attr(content='goto').html
Traceback (most recent call last):
....
ValueError: You must give a content param to <URL http://localhost/view attrs(content="goto")> generate anchor tags
>>> str(u['foo=bar%20stuff'])
'http://localhost/view?foo=bar+stuff'
"""
default_params = {'tag': 'a'}
def __str__(self):
return self.href
def _get_content(self):
if not self.params.get('content'):
raise ValueError(
"You must give a content param to %r generate anchor tags"
% self)
return self.params['content']
def _add_vars(self, vars):
url = self
for name in ('confirm', 'content'):
if name in vars:
url = url.param(**{name: vars.pop(name)})
if 'target' in vars:
url = url.attr(target=vars.pop('target'))
return url.var(**vars)
def _add_positional(self, args):
return self.addpath(*args)
def _html_attrs(self):
attrs = self.attrs.items()
attrs.insert(0, ('href', self.href))
if self.params.get('confirm'):
attrs.append(('onclick', 'return confirm(%s)'
% js_repr(self.params['confirm'])))
return attrs
def onclick_goto__get(self):
return 'location.href=%s; return false' % js_repr(self.href)
onclick_goto = property(onclick_goto__get)
def button__get(self):
return self.become(Button)
button = property(button__get)
def js_popup__get(self):
return self.become(JSPopup)
js_popup = property(js_popup__get)
class Image(URLResource):
r"""
>>> i = Image('/images')
>>> i = i / '/foo.png'
>>> i.html
'<img src="/images/foo.png" />'
>>> str(i['alt=foo'])
'<img src="/images/foo.png" alt="foo" />'
>>> i.href
'/images/foo.png'
"""
default_params = {'tag': 'img'}
def __str__(self):
return self.html
def _get_content(self):
return None
def _add_vars(self, vars):
return self.attr(**vars)
def _add_positional(self, args):
return self.addpath(*args)
def _html_attrs(self):
attrs = self.attrs.items()
attrs.insert(0, ('src', self.href))
return attrs
class Button(URLResource):
r"""
>>> u = URL('/')
>>> u = u / 'delete'
>>> b = u.button['confirm=Sure?'](id=5, content='del')
>>> str(b)
'<button onclick="if (confirm(\'Sure?\')) {location.href=\'/delete?id=5\'}; return false">del</button>'
"""
default_params = {'tag': 'button'}
def __str__(self):
return self.html
def _get_content(self):
if self.params.get('content'):
return self.params['content']
if self.attrs.get('value'):
return self.attrs['content']
# @@: Error?
return None
def _add_vars(self, vars):
button = self
if 'confirm' in vars:
button = button.param(confirm=vars.pop('confirm'))
if 'content' in vars:
button = button.param(content=vars.pop('content'))
return button.var(**vars)
def _add_positional(self, args):
return self.addpath(*args)
def _html_attrs(self):
attrs = self.attrs.items()
onclick = 'location.href=%s' % js_repr(self.href)
if self.params.get('confirm'):
onclick = 'if (confirm(%s)) {%s}' % (
js_repr(self.params['confirm']), onclick)
onclick += '; return false'
attrs.insert(0, ('onclick', onclick))
return attrs
class JSPopup(URLResource):
r"""
>>> u = URL('/')
>>> u = u / 'view'
>>> j = u.js_popup(content='view')
>>> j.html
'<a href="/view" onclick="window.open(\'/view\', \'_blank\'); return false" target="_blank">view</a>'
"""
default_params = {'tag': 'a', 'target': '_blank'}
def _add_vars(self, vars):
button = self
for var in ('width', 'height', 'stripped', 'content'):
if var in vars:
button = button.param(**{var: vars.pop(var)})
return button.var(**vars)
def _window_args(self):
p = self.params
features = []
if p.get('stripped'):
p['location'] = p['status'] = p['toolbar'] = '0'
for param in 'channelmode directories fullscreen location menubar resizable scrollbars status titlebar'.split():
if param not in p:
continue
v = p[param]
if v not in ('yes', 'no', '1', '0'):
if v:
v = '1'
else:
v = '0'
features.append('%s=%s' % (param, v))
for param in 'height left top width':
if not p.get(param):
continue
features.append('%s=%s' % (param, p[param]))
args = [self.href, p['target']]
if features:
args.append(','.join(features))
return ', '.join(map(js_repr, args))
def _html_attrs(self):
attrs = self.attrs.items()
onclick = ('window.open(%s); return false'
% self._window_args())
attrs.insert(0, ('target', self.params['target']))
attrs.insert(0, ('onclick', onclick))
attrs.insert(0, ('href', self.href))
return attrs
def _get_content(self):
if not self.params.get('content'):
raise ValueError(
"You must give a content param to %r generate anchor tags"
% self)
return self.params['content']
def _add_positional(self, args):
return self.addpath(*args)
if __name__ == '__main__':
import doctest
doctest.testmod()