Source code for django_tables2.columns.linkcolumn

# coding: utf-8
from __future__ import absolute_import, unicode_literals

from django.utils.html import format_html

from django_tables2.utils import Accessor, AttributeDict

from .base import Column, library

try:
    from django.urls import reverse
except ImportError:
    # to keep backward (Django <= 1.9) compatibility
    from django.core.urlresolvers import reverse


class BaseLinkColumn(Column):
    '''
    The base for other columns that render links.

    Arguments:
        text (str or callable): If set, this value will be used to render the
            text inside link instead of value. The callable gets the record
            being rendered as argument.
        attrs (dict): In addition to *attrs* keys supported by `~.Column`, the
            following are available:

             - *a* -- ``<a>`` in ``<td>`` elements.
    '''
    def __init__(self, attrs=None, text=None, *args, **kwargs):
        kwargs['attrs'] = attrs
        self.text = text
        super(BaseLinkColumn, self).__init__(*args, **kwargs)

    def text_value(self, record, value):
        if self.text is None:
            return value
        return self.text(record) if callable(self.text) else self.text

    def render_link(self, uri, record, value, attrs=None):
        '''
        Render a hyperlink.

        Arguments:
            uri (str): URI for the hyperlink
            record: record currently being rendered
            value (str): value to be wrapped in ``<a></a>``, might be overridden
                by ``self.text``
            attrs (dict): ``<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=self.text_value(record, value)
        )

    def value(self, record, value):
        '''
        Returns the content for a specific cell similarly to `.render` however
        without any html content.
        '''
        return self.text_value(record, value)


[docs]@library.register 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.urls.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. Arguments: viewname (str): See `~django.urls.reverse`, or use `None` to use the model's `get_absolute_url` urlconf (str): See `~django.urls.reverse`. args (list): See `~django.urls.reverse`. [2]_ kwargs (dict): See `~django.urls.reverse`. [2]_ current_app (str): See `~django.urls.reverse`. attrs (dict): HTML attributes that are added to the rendered ``<a ...>...</a>`` tag. text (str or callable): Either static text, or a callable. If set, this will be used to render the text inside link instead of value (default). The callable gets the record being rendered as argument. .. [2] 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.urls.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>``. Adding attributes to the ``<a>``-tag looks like this:: class PeopleTable(tables.Table): first_name = tables.LinkColumn(attrs={ 'a': {'style': 'color: red;'} }) ''' def __init__(self, viewname=None, 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
[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): return self.render_link( self.compose_url(record, bound_column), record=record, value=value )
[docs]@library.register class RelatedLinkColumn(LinkColumn): ''' Render a link to a related object using related object's ``get_absolute_url``, same parameters as ``~.LinkColumn`` ''' def compose_url(self, record, bound_column): accessor = self.accessor if self.accessor else Accessor(bound_column.name) return accessor.resolve(record).get_absolute_url()