# coding: utf-8
from __future__ import absolute_import, unicode_literals
from django.core.urlresolvers import reverse
from django.utils.html import escape
from django.utils.safestring import mark_safe
import warnings
from .base import Column, library
from django_tables2.utils import A, AttributeDict
class BaseLinkColumn(Column):
"""
The base for other columns that render links.
Adds support for an ``a`` key in *attrs** which is added to the rendered
``<a href="...">`` tag.
"""
def __init__(self, attrs=None, *args, **kwargs):
valid = set(("a", "th", "td", "cell"))
if attrs and not set(attrs) & set(valid):
# if none of the keys in attrs are actually valid, assume it's some
# old code that should be be interpreted as {"a": ...}
warnings.warn('attrs keys must be one of %s, interpreting as {"a": %s}'
% (', '.join(valid), attrs), DeprecationWarning)
attrs = {"a": attrs}
kwargs['attrs'] = attrs
super(BaseLinkColumn, self).__init__(*args, **kwargs)
def render_link(self, uri, text, attrs=None):
"""
Render a hyperlink.
:param uri: URI for the hyperlink
:param text: value wrapped in ``<a></a>``
:param attrs: ``<a>`` tag attributes
"""
attrs = AttributeDict(attrs if attrs is not None else
self.attrs.get('a', {}))
attrs['href'] = uri
html = '<a {attrs}>{text}</a>'.format(
attrs=attrs.as_html(),
text=escape(text)
)
return mark_safe(html)
@library.register
[docs]class LinkColumn(BaseLinkColumn):
"""
Renders a normal value as an internal hyperlink to another page.
It's common to have the primary value in a row hyperlinked to the page
dedicated to that record.
The first arguments are identical to that of
`~django.core.urlresolvers.reverse` and allows an internal URL to be
described. The last argument *attrs* allows custom HTML attributes to
be added to the rendered ``<a href="...">`` tag.
:param viewname: See `~django.core.urlresolvers.reverse`.
:param urlconf: See `~django.core.urlresolvers.reverse`.
:param args: See `~django.core.urlresolvers.reverse`. **
:param kwargs: See `~django.core.urlresolvers.reverse`. **
:param current_app: See `~django.core.urlresolvers.reverse`.
:param attrs: a `dict` of HTML attributes that are added to
the rendered ``<input type="checkbox" .../>`` tag
** In order to create a link to a URL that relies on information in the
current row, `.Accessor` objects can be used in the *args* or
*kwargs* arguments. The accessor will be resolved using the row's record
before `~django.core.urlresolvers.reverse` is called.
Example:
.. code-block:: python
# models.py
class Person(models.Model):
name = models.CharField(max_length=200)
# urls.py
urlpatterns = patterns('',
url('people/(\d+)/', views.people_detail, name='people_detail')
)
# tables.py
from django_tables2.utils import A # alias for Accessor
class PeopleTable(tables.Table):
name = tables.LinkColumn('people_detail', args=[A('pk')])
In addition to *attrs* keys supported by `.Column`, the following are
available:
- *a* -- ``<a>`` elements in ``<td>``.
"""
def __init__(self, viewname, urlconf=None, args=None, kwargs=None,
current_app=None, attrs=None, **extra):
super(LinkColumn, self).__init__(attrs, **extra)
self.viewname = viewname
self.urlconf = urlconf
self.args = args
self.kwargs = kwargs
self.current_app = current_app
def render(self, value, record, bound_column): # pylint: disable=W0221
viewname = (self.viewname.resolve(record)
if isinstance(self.viewname, A)
else self.viewname)
# The following params + if statements create optional arguments to
# pass to Django's reverse() function.
params = {}
if self.urlconf:
params['urlconf'] = (self.urlconf.resolve(record)
if isinstance(self.urlconf, A)
else self.urlconf)
if self.args:
params['args'] = [a.resolve(record) if isinstance(a, A) else a
for a in self.args]
if self.kwargs:
params['kwargs'] = {}
for key, val in self.kwargs.items():
# If we're dealing with an Accessor (A), resolve it, otherwise
# use the value verbatim.
params['kwargs'][str(key)] = (val.resolve(record)
if isinstance(val, A) else val)
if self.current_app:
params['current_app'] = (self.current_app.resolve(record)
if isinstance(self.current_app, A)
else self.current_app)
return self.render_link(reverse(viewname, **params), text=value)