# coding: utf-8
from __future__ import absolute_import, unicode_literals
import warnings
from django.core.urlresolvers import reverse
from django.utils.html import format_html
from django_tables2.utils import Accessor, AttributeDict
from .base import Column, library
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):
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
return format_html('<a {attrs}>{text}</a>',
attrs=attrs.as_html(),
text=text)
@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. If this argument is `None`, then `get_absolute_url`.
(see Django references) will be used.
The last argument *attrs* allows custom HTML attributes to be added to the
rendered ``<a href="...">`` tag.
:param viewname: See `~django.core.urlresolvers.reverse`.
Or use `None` to use Model's `get_absolute_url`
: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
:param text: Either static text, or a callable. If set, this
value will be used to render the text inside link
instead of value (default)
** 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 order to override the text value (i.e. <a ... >text</a>) consider
the following example:
.. code-block:: python
# tables.py
from django_tables2.utils import A # alias for Accessor
class PeopleTable(tables.Table):
name = tables.LinkColumn('people_detail', text='static text', args=[A('pk')])
age = tables.LinkColumn('people_detail', text=lambda record: record.name, args=[A('pk')])
In the first example, a static text would be rendered ('static text')
In the second example, you can specify a callable which accepts a record object (and thus
can return anything from it)
In addition to *attrs* keys supported by `.Column`, the following are
available:
- *a* -- ``<a>`` elements in ``<td>``.
"""
def __init__(self, viewname=None, urlconf=None, args=None, kwargs=None,
current_app=None, attrs=None, text=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
self.text_value = text
[docs] def compose_url(self, record, *args, **kwargs):
'''Compose the url if the column is constructed with a viewname.'''
if self.viewname is None:
if not hasattr(record, 'get_absolute_url'):
raise TypeError('if viewname=None, record must define a get_absolute_url')
return record.get_absolute_url()
def resolve_if_accessor(val):
return val.resolve(record) if isinstance(val, Accessor) else val
viewname = resolve_if_accessor(self.viewname)
# Collect the optional arguments for django's reverse()
params = {}
if self.urlconf:
params['urlconf'] = resolve_if_accessor(self.urlconf)
if self.args:
params['args'] = [resolve_if_accessor(a) for a in self.args]
if self.kwargs:
params['kwargs'] = {key: resolve_if_accessor(val) for key, val in self.kwargs.items()}
if self.current_app:
params['current_app'] = resolve_if_accessor(self.current_app)
return reverse(viewname, **params)
def render(self, value, record, bound_column):
text_value = value
if self.text_value:
text_value = self.text_value
if callable(text_value):
text_value = text_value(record)
return self.render_link(self.compose_url(record, bound_column), text=text_value)
@library.register
class RelatedLinkColumn(LinkColumn):
'''
Render a link to a related object using related object's ``get_absolute_url``
'''
def compose_url(self, record, bound_column):
accessor = self.accessor if self.accessor else Accessor(bound_column)
return accessor.resolve(record).get_absolute_url()