tuskar-ui/horizon/tables/base.py
Gabriel Hurley 44f670e104 Allows row status to be determined as the aggregate of multiple columns.
Instances table handles both status columns correctly now. Fixes bug 948419.
Syspanel instances table no longer has "launch instance" action. Fixes bug 952609.
Allows ajax-updating for volumes table. Fixes bug 948396.

Change-Id: I8657c79d0ab7ec5972cc7c4886d7f009a1710876
2012-03-11 17:13:31 -07:00

953 lines
36 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2012 Nebula, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import collections
import copy
import logging
from operator import attrgetter
import sys
from django import forms
from django import template
from django.conf import settings
from django.contrib import messages
from django.core import urlresolvers
from django.template.loader import render_to_string
from django.utils import http
from django.utils.datastructures import SortedDict
from django.utils.html import escape
from django.utils.translation import ugettext as _
from django.utils.safestring import mark_safe
from django.utils import termcolors
from horizon import exceptions
from .actions import FilterAction, LinkAction
LOG = logging.getLogger(__name__)
PALETTE = termcolors.PALETTES[termcolors.DEFAULT_PALETTE]
STRING_SEPARATOR = "__"
class Column(object):
""" A class which represents a single column in a :class:`.DataTable`.
.. attribute:: transform
A string or callable. If ``transform`` is a string, it should be the
name of the attribute on the underlying data class which
should be displayed in this column. If it is a callable, it
will be passed the current row's data at render-time and should
return the contents of the cell. Required.
.. attribute:: verbose_name
The name for this column which should be used for display purposes.
Defaults to the value of ``transform`` with the first letter
of each word capitalized.
.. attribute:: sortable
Boolean to determine whether this column should be sortable or not.
Defaults to False.
.. attribute:: hidden
Boolean to determine whether or not this column should be displayed
when rendering the table. Default: ``False``.
.. attribute:: link
A string or callable which returns a URL which will be wrapped around
this column's text as a link.
.. attribute:: status
Boolean designating whether or not this column represents a status
(i.e. "enabled/disabled", "up/down", "active/inactive").
Default: ``False``.
.. attribute:: status_choices
A tuple of tuples representing the possible data values for the
status column and their associated boolean equivalent. Positive
states should equate to ``True``, negative states should equate
to ``False``, and indeterminate states should be ``None``.
Values are compared in a case-insensitive manner.
Example (these are also the default values)::
status_choices = (
('enabled', True),
('true', True)
('up', True),
('active', True),
('on', True),
('none', None),
('unknown', None),
('', None),
('disabled', False),
('down', False),
('false', False),
('inactive', False),
('off', False),
)
.. attribute:: empty_value
A string to be used for cells which have no data. Defaults to an
empty string.
.. attribute:: filters
A list of functions (often template filters) to be applied to the
value of the data for this column prior to output. This is effectively
a shortcut for writing a custom ``transform`` function in simple cases.
"""
# Used to retain order when instantiating columns on a table
creation_counter = 0
# Used for special auto-generated columns
auto = None
transform = None
name = None
verbose_name = None
status_choices = (
('enabled', True),
('true', True),
('up', True),
('active', True),
('on', True),
('none', None),
('unknown', None),
('', None),
('disabled', False),
('down', False),
('false', False),
('inactive', False),
('off', False),
)
def __init__(self, transform, verbose_name=None, sortable=False,
link=None, hidden=False, attrs=None, status=False,
status_choices=None, empty_value=None, filters=None):
if callable(transform):
self.transform = transform
self.name = transform.__name__
else:
self.transform = unicode(transform)
self.name = self.transform
self.sortable = sortable
# Empty string is a valid value for verbose_name
if verbose_name is None:
verbose_name = self.transform.title()
else:
verbose_name = verbose_name
self.verbose_name = unicode(verbose_name)
self.link = link
self.hidden = hidden
self.status = status
self.empty_value = empty_value or '-'
self.filters = filters or []
if status_choices:
self.status_choices = status_choices
self.creation_counter = Column.creation_counter
Column.creation_counter += 1
self.attrs = {"classes": []}
self.attrs.update(attrs or {})
# Make sure we have a mutable list.
self.attrs['classes'] = list(self.attrs['classes'])
if self.sortable:
self.attrs['classes'].append("sortable")
if self.hidden:
self.attrs['classes'].append("hide")
def __unicode__(self):
return self.verbose_name
def __repr__(self):
return '<%s: %s>' % (self.__class__.__name__, self.name)
def get_data(self, datum):
"""
Returns the appropriate data for this column from the given input.
The return value will be either the attribute specified for this column
or the return value of the attr:`~horizon.tables.Column.transform`
method for this column.
"""
datum_id = self.table.get_object_id(datum)
if datum_id in self.table._data_cache[self]:
return self.table._data_cache[self][datum_id]
# Callable transformations
if callable(self.transform):
data = self.transform(datum)
# Basic object lookups
elif hasattr(datum, self.transform):
data = getattr(datum, self.transform, None)
# Dict lookups
elif isinstance(datum, collections.Iterable) and \
self.transform in datum:
data = datum.get(self.transform)
else:
if settings.DEBUG:
msg = _("The attribute %(attr)s doesn't exist on "
"%(obj)s.") % {'attr': self.transform, 'obj': datum}
msg = termcolors.colorize(msg, **PALETTE['ERROR'])
LOG.warning(msg)
data = None
for filter_func in self.filters:
data = filter_func(data)
self.table._data_cache[self][datum_id] = data
return self.table._data_cache[self][datum_id]
def get_classes(self):
""" Returns a flattened string of the column's CSS classes. """
return " ".join(self.attrs['classes'])
def get_link_url(self, datum):
""" Returns the final value for the column's ``link`` property.
If ``link`` is a callable, it will be passed the current data object
and should return a URL. Otherwise ``get_link_url`` will attempt to
call ``reverse`` on ``link`` with the object's id as a parameter.
Failing that, it will simply return the value of ``link``.
"""
obj_id = self.table.get_object_id(datum)
if callable(self.link):
return self.link(datum)
try:
return urlresolvers.reverse(self.link, args=(obj_id,))
except urlresolvers.NoReverseMatch:
return self.link
class Row(object):
""" Represents a row in the table.
When iterated, the ``Row`` instance will yield each of its cells.
.. attribute:: table
The table which this row belongs to.
.. attribute:: datum
The data object which this row represents.
.. attribute:: id
A string uniquely representing this row composed of the table name
and the row data object's identifier.
.. attribute:: cells
The cells belonging to this row stored in a ``SortedDict`` object.
This attribute is populated during instantiation.
.. attribute:: status
Boolean value representing the status of this row calculated from
the values of the table's ``status_columns`` if they are set.
.. attribute:: status_class
Returns a css class for the status of the row based on ``status``.
"""
def __init__(self, table, datum):
self.table = table
self.datum = datum
id_vals = {"table": self.table.name,
"sep": STRING_SEPARATOR,
"id": table.get_object_id(datum)}
self.id = "%(table)s%(sep)srow%(sep)s%(id)s" % id_vals
# Compile all the cells on instantiation
cells = []
for column in table.columns.values():
if column.auto == "multi_select":
widget = forms.CheckboxInput(check_test=False)
# Convert value to string to avoid accidental type conversion
data = widget.render('object_ids',
unicode(table.get_object_id(datum)))
table._data_cache[column][table.get_object_id(datum)] = data
elif column.auto == "actions":
data = table.render_row_actions(datum)
table._data_cache[column][table.get_object_id(datum)] = data
else:
data = column.get_data(datum)
cell = Cell(datum, data, column, self)
cells.append((column.name or column.auto, cell))
self.cells = SortedDict(cells)
@property
def status(self):
column_names = self.table._meta.status_columns
if column_names:
statuses = dict([(column_name, self.cells[column_name].status) for
column_name in column_names])
return self.table.calculate_row_status(statuses)
@property
def status_class(self):
column_names = self.table._meta.status_columns
if column_names:
return self.table.get_row_status_class(self.status)
else:
return ''
def render(self):
return render_to_string("horizon/common/_data_table_row.html",
{"row": self})
def get_cells(self):
""" Returns the bound cells for this row in order. """
return self.cells.values()
def __repr__(self):
return '<%s: %s>' % (self.__class__.__name__, self.id)
def __iter__(self):
return iter(self.cells.values())
class Cell(object):
""" Represents a single cell in the table. """
def __init__(self, datum, data, column, row, attrs=None):
self.datum = datum
self.data = data
self.column = column
self.row = row
self.attrs = {'classes': []}
self.attrs.update(attrs or {})
def __repr__(self):
return '<%s: %s, %s>' % (self.__class__.__name__,
self.column.name,
self.row.id)
@property
def value(self):
"""
Returns a formatted version of the data for final output.
This takes into consideration the
:attr:`~horizon.tables.Column.link`` and
:attr:`~horizon.tables.Column.empty_value`
attributes.
"""
try:
data = self.column.get_data(self.datum) or self.column.empty_value
except:
data = None
exc_info = sys.exc_info()
raise template.TemplateSyntaxError, exc_info[1], exc_info[2]
if self.column.link:
url = self.column.get_link_url(self.datum)
# Escape the data inside while allowing our HTML to render
data = mark_safe('<a href="%s">%s</a>' % (url, escape(data)))
return data
@property
def status(self):
""" Gets the status for the column based on the cell's data. """
# Deal with status column mechanics based in this cell's data
if hasattr(self, '_status'):
return self._status
if self.column.status or \
self.column.name in self.column.table._meta.status_columns:
#returns the first matching status found
data_value_lower = unicode(self.data).lower()
for status_name, status_value in self.column.status_choices:
if unicode(status_name).lower() == data_value_lower:
self._status = status_value
return self._status
self._status = None
return self._status
def get_status_class(self, status):
""" Returns a css class name determined by the status value. """
if status is True:
return "status_up"
elif status is False:
return "status_down"
else:
return "status_unknown"
def get_classes(self):
""" Returns a flattened string of the cell's CSS classes. """
union = set(self.attrs['classes']) | set(self.column.attrs['classes'])
if self.column.status:
union.add(self.get_status_class(self.status))
return " ".join(union)
class DataTableOptions(object):
""" Contains options for :class:`.DataTable` objects.
.. attribute:: name
A short name or slug for the table.
.. attribute:: verbose_name
A more verbose name for the table meant for display purposes.
.. attribute:: columns
A list of column objects or column names. Controls ordering/display
of the columns in the table.
.. attribute:: table_actions
A list of action classes derived from the :class:`.Action` class.
These actions will handle tasks such as bulk deletion, etc. for
multiple objects at once.
.. attribute:: row_actions
A list similar to ``table_actions`` except tailored to appear for
each row. These actions act on a single object at a time.
.. attribute:: actions_column
Boolean value to control rendering of an additional column containing
the various actions for each row. Defaults to ``True`` if any actions
are specified in the ``row_actions`` option.
.. attribute:: multi_select
Boolean value to control rendering of an extra column with checkboxes
for selecting multiple objects in the table. Defaults to ``True`` if
any actions are specified in the ``table_actions`` option.
.. attribute:: filter
Boolean value to control the display of the "filter" search box
in the table actions. By default it checks whether or not an instance
of :class:`.FilterAction` is in :attr:`.table_actions`.
.. attribute:: template
String containing the template which should be used to render the
table. Defaults to ``"horizon/common/_data_table.html"``.
.. attribute:: context_var_name
The name of the context variable which will contain the table when
it is rendered. Defaults to ``"table"``.
.. attribute:: status_columns
A list or tuple of column names which represents the "state"
of the data object being represented.
If ``status_columns`` is set, when the rows are rendered the value
of this column will be used to add an extra class to the row in
the form of ``"status_up"`` or ``"status_down"`` for that row's
data.
The row status is used by other Horizon components to trigger tasks
such as dynamic AJAX updating.
.. attribute:: row_class
The class which should be used for rendering the rows of this table.
Optional. Default: :class:`~horizon.tables.Row`.
.. attribute:: column_class
The class which should be used for handling the columns of this table.
Optional. Default: :class:`~horizon.tables.Column`.
"""
def __init__(self, options):
self.name = getattr(options, 'name', self.__class__.__name__)
verbose_name = getattr(options, 'verbose_name', None) \
or self.name.title()
self.verbose_name = unicode(verbose_name)
self.columns = getattr(options, 'columns', None)
self.status_columns = getattr(options, 'status_columns', [])
self.table_actions = getattr(options, 'table_actions', [])
self.row_actions = getattr(options, 'row_actions', [])
self.row_class = getattr(options, 'row_class', Row)
self.column_class = getattr(options, 'column_class', Column)
# Set self.filter if we have any FilterActions
filter_actions = [action for action in self.table_actions if
issubclass(action, FilterAction)]
if len(filter_actions) > 1:
raise NotImplementedError("Multiple filter actions is not "
"currently supported.")
self.filter = getattr(options, 'filter', len(filter_actions) > 0)
if len(filter_actions) == 1:
self._filter_action = filter_actions.pop()
else:
self._filter_action = None
self.template = 'horizon/common/_data_table.html'
self.row_actions_template = \
'horizon/common/_data_table_row_actions.html'
self.table_actions_template = \
'horizon/common/_data_table_table_actions.html'
self.context_var_name = unicode(getattr(options,
'context_var_nam',
'table'))
self.actions_column = getattr(options,
'actions_column',
len(self.row_actions) > 0)
self.multi_select = getattr(options,
'multi_select',
len(self.table_actions) > 0)
# Set runtime table defaults; not configurable.
self.has_more_data = False
class DataTableMetaclass(type):
""" Metaclass to add options to DataTable class and collect columns. """
def __new__(mcs, name, bases, attrs):
# Process options from Meta
attrs["_meta"] = opts = DataTableOptions(attrs.get("Meta", None))
# Gather columns; this prevents the column from being an attribute
# on the DataTable class and avoids naming conflicts.
columns = [(column_name, attrs.pop(column_name)) for \
column_name, obj in attrs.items() \
if isinstance(obj, opts.column_class)]
# add a name attribute to each column
for column_name, column in columns:
column.name = column_name
columns.sort(key=lambda x: x[1].creation_counter)
# Iterate in reverse to preserve final order
for base in bases[::-1]:
if hasattr(base, 'base_columns'):
columns = base.base_columns.items() + columns
attrs['base_columns'] = SortedDict(columns)
if opts.columns:
# Remove any columns that weren't declared if we're being explicit
# NOTE: we're iterating a COPY of the list here!
for column_data in columns[:]:
if column_data[0] not in opts.columns:
columns.pop(columns.index(column_data))
# Re-order based on declared columns
columns.sort(key=lambda x: attrs['_meta'].columns.index(x[0]))
# Add in our auto-generated columns
if opts.multi_select:
multi_select = opts.column_class("multi_select",
verbose_name="")
multi_select.attrs = {'classes': ('multi_select_column',)}
multi_select.auto = "multi_select"
columns.insert(0, ("multi_select", multi_select))
if opts.actions_column:
actions_column = opts.column_class("actions",
verbose_name=_("Actions"))
actions_column.attrs = {'classes': ('actions_column',)}
actions_column.auto = "actions"
columns.append(("actions", actions_column))
attrs['columns'] = SortedDict(columns)
# Gather and register actions for later access since we only want
# to instantiate them once.
# (list() call gives deterministic sort order, which sets don't have.)
actions = list(set(opts.row_actions) | set(opts.table_actions))
actions.sort(key=attrgetter('name'))
actions_dict = SortedDict([(action.name, action()) \
for action in actions])
attrs['base_actions'] = actions_dict
if opts._filter_action:
# Replace our filter action with the instantiated version
opts._filter_action = actions_dict[opts._filter_action.name]
# Create our new class!
return type.__new__(mcs, name, bases, attrs)
class DataTable(object):
""" A class which defines a table with all data and associated actions.
.. attribute:: name
String. Read-only access to the name specified in the
table's Meta options.
.. attribute:: multi_select
Boolean. Read-only access to whether or not this table
should display a column for multi-select checkboxes.
.. attribute:: data
Read-only access to the data this table represents.
.. attribute:: filtered_data
Read-only access to the data this table represents, filtered by
the :meth:`~horizon.tables.FilterAction.filter` method of the table's
:class:`~horizon.tables.FilterAction` class (if one is provided)
using the current request's query parameters.
"""
__metaclass__ = DataTableMetaclass
def __init__(self, request, data=None, **kwargs):
self._meta.request = request
self._meta.data = data
self._populate_data_cache()
self.kwargs = kwargs
for column in self.columns.values():
column.table = self
# Associate these actions with this table
for action in self.base_actions.values():
action.table = self
if self._meta._filter_action:
param_name = self._meta._filter_action.get_param_name()
q = self._meta.request.POST.get(param_name, '')
self._meta._filter_action.filter_string = q
def __unicode__(self):
return self._meta.verbose_name
def __repr__(self):
return '<%s: %s>' % (self.__class__.__name__, self.name)
@property
def name(self):
return self._meta.name
@property
def data(self):
return self._meta.data
@data.setter
def data(self, data):
self._meta.data = data
@property
def multi_select(self):
return self._meta.multi_select
@property
def filtered_data(self):
if not hasattr(self, '_filtered_data'):
self._filtered_data = self.data
if self._meta.filter and self._meta._filter_action:
action = self._meta._filter_action
self._filtered_data = action.filter(self,
self.data,
action.filter_string)
return self._filtered_data
def _populate_data_cache(self):
self._data_cache = {}
# Set up hash tables to store data points for each column
for column in self.get_columns():
self._data_cache[column] = {}
def _filter_action(self, action, request, datum=None):
try:
# Catch user errors in permission functions here
return action._allowed(request, datum)
except Exception:
LOG.exception("Error while checking action permissions.")
return None
def render(self):
""" Renders the table using the template from the table options. """
table_template = template.loader.get_template(self._meta.template)
extra_context = {self._meta.context_var_name: self}
context = template.RequestContext(self._meta.request, extra_context)
return table_template.render(context)
def get_absolute_url(self):
""" Returns the canonical URL for this table.
This is used for the POST action attribute on the form element
wrapping the table. In many cases it is also useful for redirecting
after a successful action on the table.
For convenience it defaults to the value of
``request.get_full_path()``, e.g. the path at which the table
was requested.
"""
return self._meta.request.get_full_path()
def get_empty_message(self):
""" Returns the message to be displayed when there is no data. """
return _("No items to display.")
def get_object_by_id(self, lookup):
"""
Returns the data object from the table's dataset which matches
the ``lookup`` parameter specified. An error will be raised if
the match is not a single data object.
Uses :meth:`~horizon.tables.DataTable.get_object_id` internally.
"""
matches = [datum for datum in self.data if
self.get_object_id(datum) == lookup]
if len(matches) > 1:
raise ValueError("Multiple matches were returned for that id: %s."
% matches)
if not matches:
raise exceptions.Http302(self.get_absolute_url(),
_('No match returned for the id "%s".')
% lookup)
return matches[0]
def get_table_actions(self):
""" Returns a list of the action instances for this table. """
bound_actions = [self.base_actions[action.name] for
action in self._meta.table_actions]
return [action for action in bound_actions if
self._filter_action(action, self._meta.request)]
def get_row_actions(self, datum):
""" Returns a list of the action instances for a specific row. """
bound_actions = []
for action in self._meta.row_actions:
# Copy to allow modifying properties per row
bound_action = copy.copy(self.base_actions[action.name])
# Remove disallowed actions.
if not self._filter_action(bound_action,
self._meta.request,
datum):
continue
# Hook for modifying actions based on data. No-op by default.
bound_action.update(self._meta.request, datum)
# Pre-create the URL for this link with appropriate parameters
if issubclass(bound_action.__class__, LinkAction):
bound_action.bound_url = bound_action.get_link_url(datum)
bound_actions.append(bound_action)
return bound_actions
def render_table_actions(self):
""" Renders the actions specified in ``Meta.table_actions``. """
template_path = self._meta.table_actions_template
table_actions_template = template.loader.get_template(template_path)
bound_actions = self.get_table_actions()
extra_context = {"table_actions": bound_actions}
if self._meta.filter:
extra_context["filter"] = self._meta._filter_action
context = template.RequestContext(self._meta.request, extra_context)
return table_actions_template.render(context)
def render_row_actions(self, datum):
"""
Renders the actions specified in ``Meta.row_actions`` using the
current row data. """
template_path = self._meta.row_actions_template
row_actions_template = template.loader.get_template(template_path)
bound_actions = self.get_row_actions(datum)
extra_context = {"row_actions": bound_actions,
"row_id": self.get_object_id(datum)}
context = template.RequestContext(self._meta.request, extra_context)
return row_actions_template.render(context)
def parse_action(self, action_string):
"""
Parses the ``action`` parameter (a string) sent back with the
POST data. By default this parses a string formatted as
``{{ table_name }}__{{ action_name }}__{{ row_id }}`` and returns
each of the pieces. The ``row_id`` is optional.
"""
if action_string:
bits = action_string.split(STRING_SEPARATOR)
bits.reverse()
table = bits.pop()
action = bits.pop()
try:
object_id = bits.pop()
except IndexError:
object_id = None
return table, action, object_id
def take_action(self, action_name, obj_id=None, obj_ids=None):
"""
Locates the appropriate action and routes the object
data to it. The action should return an HTTP redirect
if successful, or a value which evaluates to ``False``
if unsuccessful.
"""
# See if we have a list of ids
obj_ids = obj_ids or self._meta.request.POST.getlist('object_ids')
action = self.base_actions.get(action_name, None)
if not action or action.method != self._meta.request.method:
# We either didn't get an action or we're being hacked. Goodbye.
return None
# Meanhile, back in Gotham...
if not action.requires_input or obj_id or obj_ids:
if obj_id:
obj_id = self.sanitize_id(obj_id)
if obj_ids:
obj_ids = [self.sanitize_id(i) for i in obj_ids]
# Single handling is easy
if not action.handles_multiple:
response = action.single(self, self._meta.request, obj_id)
# Otherwise figure out what to pass along
else:
if obj_id and not obj_ids:
obj_ids = [obj_id]
response = action.multiple(self, self._meta.request, obj_ids)
return response
elif action and action.requires_input and not (obj_id or obj_ids):
messages.info(self._meta.request,
_("Please select a row before taking that action."))
return None
def _check_handler(self):
""" Determine whether the request should be handled by this table. """
request = self._meta.request
if request.method == "POST" and "action" in request.POST:
table, action, obj_id = self.parse_action(request.POST["action"])
elif "table" in request.GET and "action" in request.GET:
table = request.GET["table"]
action = request.GET["action"]
obj_id = request.GET.get("obj_id", None)
else:
table = action = obj_id = None
return table, action, obj_id
def maybe_preempt(self):
"""
Determine whether the request should be handled by a preemptive action
on this table before loading any data.
"""
table_name, action_name, obj_id = self._check_handler()
preemptive_actions = [action for action in self.base_actions.values()
if action.preempt]
if table_name == self.name and action_name:
for action in preemptive_actions:
if action.name == action_name:
handled = self.take_action(action_name, obj_id)
if handled:
return handled
return None
def maybe_handle(self):
"""
Determine whether the request should be handled by any action on this
table after data has been loaded.
"""
table_name, action_name, obj_id = self._check_handler()
if table_name == self.name and action_name:
return self.take_action(action_name, obj_id)
return None
def sanitize_id(self, obj_id):
""" Override to modify an incoming obj_id to match existing
API data types or modify the format.
"""
return obj_id
def get_object_id(self, datum):
""" Returns the identifier for the object this row will represent.
By default this returns an ``id`` attribute on the given object,
but this can be overridden to return other values.
"""
return datum.id
def get_object_display(self, datum):
""" Returns a display name that identifies this object.
By default, this returns a ``name`` attribute from the given object,
but this can be overriden to return other values.
"""
return datum.name
def has_more_data(self):
"""
Returns a boolean value indicating whether there is more data
available to this table from the source (generally an API).
The method is largely meant for internal use, but if you want to
override it to provide custom behavior you can do so at your own risk.
"""
return self._meta.has_more_data
def get_marker(self):
"""
Returns the identifier for the last object in the current data set
for APIs that use marker/limit-based paging.
"""
return http.urlquote_plus(self.get_object_id(self.data[-1]))
def calculate_row_status(self, statuses):
"""
Returns a boolean value determining the overall row status
based on the dictionary of column name to status mappings passed in.
By default, it uses the following logic:
#. If any statuses are ``False``, return ``False``.
#. If no statuses are ``False`` but any or ``None``, return ``None``.
#. If all statuses are ``True``, return ``True``.
This provides the greatest protection against false positives without
weighting any particular columns.
The ``statuses`` parameter is passed in as a dictionary mapping
column names to their statuses in order to allow this function to
be overridden in such a way as to weight one column's status over
another should that behavior be desired.
"""
values = statuses.values()
if any([status is False for status in values]):
return False
elif any([status is None for status in values]):
return None
else:
return True
def get_row_status_class(self, status):
"""
Returns a css class name determined by the status value. This class
name is used to indicate the status of the rows in the table if
any ``status_columns`` have been specified.
"""
if status is True:
return "status_up"
elif status is False:
return "status_down"
else:
return "status_unknown"
def get_columns(self):
""" Returns this table's columns including auto-generated ones."""
return self.columns.values()
def get_rows(self):
""" Return the row data for this table broken out by columns. """
rows = []
try:
for datum in self.filtered_data:
rows.append(self._meta.row_class(self, datum))
except:
# Exceptions can be swallowed at the template level here,
# re-raising as a TemplateSyntaxError makes them visible.
LOG.exception("Error while rendering table rows.")
exc_info = sys.exc_info()
raise template.TemplateSyntaxError, exc_info[1], exc_info[2]
return rows