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| author | Tomas Sedovic <tomas@sedovic.cz> | 2013-08-08 14:26:25 +0200 |
|---|---|---|
| committer | Tomas Sedovic <tomas@sedovic.cz> | 2013-08-08 15:27:34 +0200 |
| commit | b1658b592bd7fd6f68ed33034789ed9f60ac5bd2 (patch) | |
| tree | 164b058efd990e6ff2b588651d0e055a02211017 | |
| parent | 0282ff711cdf3afcd5b184401b62fca8a4416853 (diff) | |
| download | tuskar-ui-b1658b592bd7fd6f68ed33034789ed9f60ac5bd2.tar.gz | |
Add the forked Horizon files
The following files have our local modifications over traditional Horizon so we
need to carry them around until they get in the upstream.
I've just copied the files over. We probably don't need most of the stuff in
there, so that should be cleaned up soon.
Signed-off-by: Tomas Sedovic <tomas@sedovic.cz>
| -rw-r--r-- | tuskar_ui/forms.py | 6 | ||||
| -rw-r--r-- | tuskar_ui/tables.py | 1396 | ||||
| -rw-r--r-- | tuskar_ui/workflows.py | 934 |
3 files changed, 2336 insertions, 0 deletions
diff --git a/tuskar_ui/forms.py b/tuskar_ui/forms.py new file mode 100644 index 00000000..d0091010 --- /dev/null +++ b/tuskar_ui/forms.py @@ -0,0 +1,6 @@ +from django.forms import widgets + + +class NumberInput(widgets.TextInput): + input_type = 'number' + diff --git a/tuskar_ui/tables.py b/tuskar_ui/tables.py new file mode 100644 index 00000000..7a0edaed --- /dev/null +++ b/tuskar_ui/tables.py @@ -0,0 +1,1396 @@ +# 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.conf import settings +from django.core import urlresolvers +from django import forms +from django.http import HttpResponse +from django import template +from django.template.defaultfilters import truncatechars +from django.template.loader import render_to_string +from django.utils.datastructures import SortedDict +from django.utils.html import escape +from django.utils import http +from django.utils.http import urlencode +from django.utils.safestring import mark_safe +from django.utils import termcolors +from django.utils.translation import ugettext_lazy as _ + +from horizon import conf +from horizon import exceptions +from horizon import messages +from horizon.tables.actions import FilterAction +from horizon.tables.actions import LinkAction +from horizon.utils import html + + +LOG = logging.getLogger(__name__) +PALETTE = termcolors.PALETTES[termcolors.DEFAULT_PALETTE] +STRING_SEPARATOR = "__" + + +class Column(html.HTMLElement): + """ 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 ``True``. + + .. 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:: allowed_data_types + + A list of data types for which the link should be created. + Default is an empty list (``[]``). + + When the list is empty and the ``link`` attribute is not None, all the + rows under this column will be links. + + .. 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:: display_choices + + A tuple of tuples representing the possible values to substitute + the data when displayed in the column cell. + + .. attribute:: empty_value + + A string or callable to be used for cells which have no data. + Defaults to the string ``"-"``. + + .. attribute:: summation + + A string containing the name of a summation method to be used in + the generation of a summary row for this column. By default the + options are ``"sum"`` or ``"average"``, which behave as expected. + Optional. + + .. 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. + + .. attribute:: classes + + An iterable of CSS classes which should be added to this column. + Example: ``classes=('foo', 'bar')``. + + .. attribute:: attrs + + A dict of HTML attribute strings which should be added to this column. + Example: ``attrs={"data-foo": "bar"}``. + + .. attribute:: truncate + + An integer for the maximum length of the string in this column. If the + data in this column is larger than the supplied number, the data for + this column will be truncated and an ellipsis will be appended to the + truncated data. + Defaults to ``None``. + + .. attribute:: link_classes + + An iterable of CSS classes which will be added when the column's text + is displayed as a link. + Example: ``classes=('link-foo', 'link-bar')``. + Defaults to ``None``. + """ + summation_methods = { + "sum": sum, + "average": lambda data: sum(data, 0.0) / len(data) + } + # Used to retain order when instantiating columns on a table + creation_counter = 0 + + 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=True, + link=None, allowed_data_types=[], hidden=False, attrs=None, + status=False, status_choices=None, display_choices=None, + empty_value=None, filters=None, classes=None, summation=None, + auto=None, truncate=None, link_classes=None, + # FIXME: Added for TableStep: + form_widget=None, form_widget_attributes=None + ): + + self.classes = list(classes or getattr(self, "classes", [])) + super(Column, self).__init__() + self.attrs.update(attrs or {}) + + if callable(transform): + self.transform = transform + self.name = transform.__name__ + else: + self.transform = unicode(transform) + self.name = self.transform + + # 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.auto = auto + self.sortable = sortable + self.verbose_name = verbose_name + self.link = link + self.allowed_data_types = allowed_data_types + self.hidden = hidden + self.status = status + self.empty_value = empty_value or '-' + self.filters = filters or [] + self.truncate = truncate + self.link_classes = link_classes or [] + self.form_widget = form_widget # FIXME: TableStep + self.form_widget_attributes = form_widget_attributes or {} # TableStep + + if status_choices: + self.status_choices = status_choices + self.display_choices = display_choices + + if summation is not None and summation not in self.summation_methods: + raise ValueError("Summation method %s must be one of %s." + % (summation, + ", ".join(self.summation_methods.keys()))) + self.summation = summation + + self.creation_counter = Column.creation_counter + Column.creation_counter += 1 + + if self.sortable and not self.auto: + self.classes.append("sortable") + if self.hidden: + self.classes.append("hide") + if self.link is not None: + self.classes.append('anchor') + + def __unicode__(self): + return unicode(self.verbose_name) + + def __repr__(self): + return '<%s: %s>' % (self.__class__.__name__, self.name) + + def get_raw_data(self, datum): + """ + Returns the raw data for this column, before any filters or formatting + are applied to it. This is useful when doing calculations on data in + the table. + """ + # 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 + return data + + def get_data(self, datum): + """ + Returns the final display data for this column from the given inputs. + + 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] + + data = self.get_raw_data(datum) + display_value = None + + if self.display_choices: + display_value = [display for (value, display) in + self.display_choices + if value.lower() == (data or '').lower()] + + if display_value: + data = display_value[0] + else: + for filter_func in self.filters: + data = filter_func(data) + + if data and self.truncate: + data = truncatechars(data, self.truncate) + + self.table._data_cache[self][datum_id] = data + + return self.table._data_cache[self][datum_id] + + def get_link_url(self, datum): + """ Returns the final value for the column's ``link`` property. + + If ``allowed_data_types`` of this column is not empty and the datum + has an assigned type, check if the datum's type is in the + ``allowed_data_types`` list. If not, the datum won't be displayed + as a link. + + 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``. + """ + if self.allowed_data_types: + data_type_name = self.table._meta.data_type_name + data_type = getattr(datum, data_type_name, None) + if data_type and (data_type not in self.allowed_data_types): + return None + 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 + + def get_summation(self): + """ + Returns the summary value for the data in this column if a + valid summation method is specified for it. Otherwise returns ``None``. + """ + if self.summation not in self.summation_methods: + return None + + summation_function = self.summation_methods[self.summation] + data = [self.get_raw_data(datum) for datum in self.table.data] + data = filter(lambda datum: datum is not None, data) + + if len(data): + summation = summation_function(data) + for filter_func in self.filters: + summation = filter_func(summation) + return summation + else: + return None + + +class Row(html.HTMLElement): + """ Represents a row in the table. + + When iterated, the ``Row`` instance will yield each of its cells. + + Rows are capable of AJAX updating, with a little added work: + + The ``ajax`` property needs to be set to ``True``, and + subclasses need to define a ``get_data`` method which returns a data + object appropriate for consumption by the table (effectively the "get" + lookup versus the table's "list" lookup). + + The automatic update interval is configurable by setting the key + ``ajax_poll_interval`` in the ``HORIZON_CONFIG`` dictionary. + Default: ``2500`` (measured in milliseconds). + + .. 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``. + + .. attribute:: ajax + + Boolean value to determine whether ajax updating for this row is + enabled. + + .. attribute:: ajax_action_name + + String that is used for the query parameter key to request AJAX + updates. Generally you won't need to change this value. + Default: ``"row_update"``. + """ + ajax = False + ajax_action_name = "row_update" + + def __init__(self, table, datum=None): + super(Row, self).__init__() + self.table = table + self.datum = datum + self.selected = False + if self.datum: + self.load_cells() + else: + self.id = None + self.cells = [] + + def load_cells(self, datum=None): + """ + Load the row's data (either provided at initialization or as an + argument to this function), initiailize all the cells contained + by this row, and set the appropriate row properties which require + the row's data to be determined. + + This function is called automatically by + :meth:`~horizon.tables.Row.__init__` if the ``datum`` argument is + provided. However, by not providing the data during initialization + this function allows for the possibility of a two-step loading + pattern when you need a row instance but don't yet have the data + available. + """ + # Compile all the cells on instantiation. + table = self.table + if datum: + self.datum = datum + else: + datum = self.datum + cells = [] + for column in table.columns.values(): + if column.auto == "multi_select": + + # FIXME: TableStep code modified + # multi_select fields in the table must be checked after + # a server action + # TODO(remove this ugly code and create proper TableFormWidget) + multi_select_values = [] + if (getattr(table, 'request', False) and + getattr(table.request, 'POST', False)): + multi_select_values = table.request.POST.getlist( + self.table._meta.multi_select_name) + + multi_select_values += getattr(table, + 'active_multi_select_values', + []) + + if unicode(table.get_object_id(datum)) in multi_select_values: + multi_select_value = lambda value: True + else: + multi_select_value = lambda value: False + widget = forms.CheckboxInput(check_test=multi_select_value) + + # Convert value to string to avoid accidental type conversion + data = widget.render(self.table._meta.multi_select_name, + unicode(table.get_object_id(datum))) + # FIXME: end of added TableStep code + + table._data_cache[column][table.get_object_id(datum)] = data + elif column.auto == "form_widget": # FIXME: Added for TableStep: + widget = column.form_widget + widget_name = "%s__%s__%s" % \ + (self.table._meta.multi_select_name, + column.name, + unicode(table.get_object_id(datum))) + + data = widget.render(widget_name, + column.get_data(datum), + column.form_widget_attributes) + 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) + + if self.ajax: + interval = conf.HORIZON_CONFIG['ajax_poll_interval'] + self.attrs['data-update-interval'] = interval + self.attrs['data-update-url'] = self.get_ajax_update_url() + self.classes.append("ajax-update") + + # Add the row's status class and id to the attributes to be rendered. + self.classes.append(self.status_class) + 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 + self.attrs['id'] = self.id + + # Add the row's display name if available + display_name = table.get_object_display(datum) + if display_name: + self.attrs['data-display'] = escape(display_name) + + def __repr__(self): + return '<%s: %s>' % (self.__class__.__name__, self.id) + + def __iter__(self): + return iter(self.cells.values()) + + @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 get_ajax_update_url(self): + table_url = self.table.get_absolute_url() + params = urlencode({"table": self.table.name, + "action": self.ajax_action_name, + "obj_id": self.table.get_object_id(self.datum)}) + return "%s?%s" % (table_url, params) + + def get_data(self, request, obj_id): + """ + Fetches the updated data for the row based on the object id + passed in. Must be implemented by a subclass to allow AJAX updating. + """ + raise NotImplementedError("You must define a get_data method on %s" + % self.__class__.__name__) + + +class Cell(html.HTMLElement): + """ Represents a single cell in the table. """ + def __init__(self, datum, data, column, row, attrs=None, classes=None): + self.classes = classes or getattr(self, "classes", []) + super(Cell, self).__init__() + self.attrs.update(attrs or {}) + + self.datum = datum + self.data = data + self.column = column + self.row = row + + 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) + if data is None: + if callable(self.column.empty_value): + data = self.column.empty_value(self.datum) + else: + data = self.column.empty_value + except: + data = None + exc_info = sys.exc_info() + raise template.TemplateSyntaxError, exc_info[1], exc_info[2] + if self.url: + link_classes = ' '.join(self.column.link_classes) + # Escape the data inside while allowing our HTML to render + data = mark_safe('<a href="%s" class="%s">%s</a>' % + (self.url, link_classes, escape(data))) + return data + + @property + def url(self): + if self.column.link: + url = self.column.get_link_url(self.datum) + if url: + return url + else: + return None + + @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_default_classes(self): + """ Returns a flattened string of the cell's CSS classes. """ + if not self.url: + self.column.classes = [cls for cls in self.column.classes + if cls != "anchor"] + column_class_string = self.column.get_final_attrs().get('class', "") + classes = set(column_class_string.split(" ")) + if self.column.status: + classes.add(self.get_status_class(self.status)) + return list(classes) + + +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:`~horizon.tables.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:: pagination_param + + The name of the query string parameter which will be used when + paginating this table. When using multiple tables in a single + view this will need to be changed to differentiate between the + tables. Default: ``"marker"``. + + .. 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`. + + .. attribute:: mixed_data_type + + A toggle to indicate if the table accepts two or more types of data. + Optional. Default: :``False`` + + .. attribute:: data_types + + A list of data types that this table would accept. Default to be an + empty list, but if the attibute ``mixed_data_type`` is set to ``True``, + then this list must have at least one element. + + .. attribute:: data_type_name + + The name of an attribute to assign to data passed to the table when it + accepts mix data. Default: ``"_table_data_type"`` + + .. attribute:: footer + + Boolean to control whether or not to show the table's footer. + Default: ``True``. + + .. attribute:: permissions + + A list of permission names which this table requires in order to be + displayed. Defaults to an empty list (``[]``). + """ + 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 = 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) + self.pagination_param = getattr(options, 'pagination_param', 'marker') + self.browser_table = getattr(options, 'browser_table', None) + self.footer = getattr(options, 'footer', True) + self.no_data_message = getattr(options, + "no_data_message", + _("No items to display.")) + self.permissions = getattr(options, 'permissions', []) + + # 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_name', + 'table')) + self.actions_column = getattr(options, + 'actions_column', + len(self.row_actions) > 0) + # FIXME: TableStep + self.multi_select_name = getattr(options, + 'multi_select_name', + 'object_ids') + self.multi_select = getattr(options, + 'multi_select', + len(self.table_actions) > 0) + + # Set runtime table defaults; not configurable. + self.has_more_data = False + + # Set mixed data type table attr + self.mixed_data_type = getattr(options, 'mixed_data_type', False) + self.data_types = getattr(options, 'data_types', []) + + # If the data_types has more than 2 elements, set mixed_data_type + # to True automatically. + if len(self.data_types) > 1: + self.mixed_data_type = True + + # However, if the mixed_data_type is set to True manually and the + # the data_types is empty, raise an errror. + if self.mixed_data_type and len(self.data_types) <= 1: + raise ValueError("If mixed_data_type is set to True in class %s, " + "data_types should has more than one types" % + self.name) + + self.data_type_name = getattr(options, + 'data_type_name', + "_table_data_type") + + +class DataTableMetaclass(type): + """ Metaclass to add options to DataTable class and collect columns. """ + def __new__(mcs, name, bases, attrs): + # Process options from Meta + class_name = name + 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 = [] + for attr_name, obj in attrs.items(): + if issubclass(type(obj), (opts.column_class, Column)): + column_instance = attrs.pop(attr_name) + column_instance.name = attr_name + column_instance.classes.append('normal_column') + columns.append((attr_name, column_instance)) + 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 the table is in a ResourceBrowser, the column number must meet + # these limits because of the width of the browser. + if opts.browser_table == "navigation" and len(columns) > 1: + raise ValueError("You can only assign one column to %s." + % class_name) + if opts.browser_table == "content" and len(columns) > 2: + raise ValueError("You can only assign two columns to %s." + % class_name) + + 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 and opts.browser_table != "navigation": + multi_select = opts.column_class("multi_select", + verbose_name="", + auto="multi_select") + multi_select.classes.append('multi_select_column') + columns.insert(0, ("multi_select", multi_select)) + if opts.actions_column: + actions_column = opts.column_class("actions", + verbose_name=_("Actions"), + auto="actions") + actions_column.classes.append('actions_column') + columns.append(("actions", actions_column)) + # Store this set of columns internally so we can copy them per-instance + 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, needs_form_wrapper=None, **kwargs): + self.request = request + self.data = data + self.kwargs = kwargs + self._needs_form_wrapper = needs_form_wrapper + self._no_data_message = self._meta.no_data_message + self.breadcrumb = None + self.current_item_id = None + self.permissions = self._meta.permissions + + # Create a new set + columns = [] + for key, _column in self._columns.items(): + column = copy.copy(_column) + column.table = self + columns.append((key, column)) + self.columns = SortedDict(columns) + self._populate_data_cache() + + # Associate these actions with this table + for action in self.base_actions.values(): + action.table = self + + self.needs_summary_row = any([col.summation + for col in self.columns.values()]) + + def __unicode__(self): + return unicode(self._meta.verbose_name) + + def __repr__(self): + return '<%s: %s>' % (self.__class__.__name__, self._meta.name) + + @property + def name(self): + return self._meta.name + + @property + def footer(self): + return self._meta.footer + + @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 + filter_string = self.get_filter_string() + request_method = self.request.method + needs_preloading = (not filter_string + and request_method == 'GET' + and action.needs_preloading) + valid_method = (request_method == action.method) + if (filter_string and valid_method) or needs_preloading: + if self._meta.mixed_data_type: + self._filtered_data = action.data_type_filter(self, + self.data, + filter_string) + else: + self._filtered_data = action.filter(self, + self.data, + filter_string) + return self._filtered_data + + def get_filter_string(self): + filter_action = self._meta._filter_action + param_name = filter_action.get_param_name() + filter_string = self.request.POST.get(param_name, '') + return filter_string + + 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 + row_matched = True + if self._meta.mixed_data_type: + row_matched = action.data_type_matched(datum) + return action._allowed(request, datum) and row_matched + except Exception: + LOG.exception("Error while checking action permissions.") + return None + + def is_browser_table(self): + if self._meta.browser_table: + return True + return False + + 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.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()`` with any query string stripped off, + e.g. the path at which the table was requested. + """ + return self.request.get_full_path().partition('?')[0] + + def get_empty_message(self): + """ Returns the message to be displayed when there is no data. """ + return self._no_data_message + + 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. + + We will convert the object id and ``lookup`` to unicode before + comparison. + + Uses :meth:`~horizon.tables.DataTable.get_object_id` internally. + """ + if not isinstance(lookup, unicode): + lookup = unicode(str(lookup), 'utf-8') + matches = [] + for datum in self.data: + obj_id = self.get_object_id(datum) + if not isinstance(obj_id, unicode): + obj_id = unicode(str(obj_id), 'utf-8') + if obj_id == lookup: + matches.append(datum) + 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] + + @property + def has_actions(self): + """ + Boolean. Indicates whether there are any available actions on this + table. + """ + if not self.base_actions: + return False + return any(self.get_table_actions()) or any(self._meta.row_actions) + + @property + def needs_form_wrapper(self): + """ + Boolean. Indicates whather this table should be rendered wrapped in + a ``<form>`` tag or not. + """ + # If needs_form_wrapper is explicitly set, defer to that. + if self._needs_form_wrapper is not None: + return self._needs_form_wrapper + # Otherwise calculate whether or not we need a form element. + return self.has_actions + + 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.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]) + bound_action.attrs = copy.copy(bound_action.attrs) + bound_action.datum = datum + # Remove disallowed actions. + if not self._filter_action(bound_action, + self.request, + datum): + continue + # Hook for modifying actions based on data. No-op by default. + bound_action.update(self.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 and \ + self._filter_action(self._meta._filter_action, self.request): + extra_context["filter"] = self._meta._filter_action + context = template.RequestContext(self.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.request, extra_context) + return row_actions_template.render(context) + + @staticmethod + def parse_action(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.request.POST.getlist('object_ids') + action = self.base_actions.get(action_name, None) + if not action or action.method != self.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.request, obj_id) + # Otherwise figure out what to pass along + else: + # Preference given to a specific id, since that implies + # the user selected an action for just one row. + if obj_id: + obj_ids = [obj_id] + response = action.multiple(self, self.request, obj_ids) + return response + elif action and action.requires_input and not (obj_id or obj_ids): + messages.info(self.request, + _("Please select a row before taking that action.")) + return None + + @classmethod + def check_handler(cls, request): + """ Determine whether the request should be handled by this table. """ + if request.method == "POST" and "action" in request.POST: + table, action, obj_id = cls.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 or by an AJAX row update before loading any data. + """ + request = self.request + table_name, action_name, obj_id = self.check_handler(request) + + if table_name == self.name: + # Handle AJAX row updating. + new_row = self._meta.row_class(self) + if new_row.ajax and new_row.ajax_action_name == action_name: + try: + datum = new_row.get_data(request, obj_id) + new_row.load_cells(datum) + error = False + except: + datum = None + error = exceptions.handle(request, ignore=True) + if request.is_ajax(): + if not error: + return HttpResponse(new_row.render()) + else: + return HttpResponse(status=error.status_code) + + preemptive_actions = [action for action in + self.base_actions.values() if action.preempt] + if 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. + """ + request = self.request + table_name, action_name, obj_id = self.check_handler(request) + 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. + + .. warning:: + + Make sure that the value returned is a unique value for the id + otherwise rendering issues can occur. + """ + 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. + """ + if hasattr(datum, 'name'): + return datum.name + return None + + 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 get_pagination_string(self): + """ Returns the query parameter string to paginate this table. """ + return "=".join([self._meta.pagination_param, self.get_marker()]) + + 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: + row = self._meta.row_class(self, datum) + if self.get_object_id(datum) == self.current_item_id: + self.selected = True + row.classes.append('current_selected') + rows.append(row) + 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 diff --git a/tuskar_ui/workflows.py b/tuskar_ui/workflows.py new file mode 100644 index 00000000..60d8a1e9 --- /dev/null +++ b/tuskar_ui/workflows.py @@ -0,0 +1,934 @@ +# 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 copy +import inspect +import logging + +from django.core import urlresolvers +from django import forms +from django.forms.forms import NON_FIELD_ERRORS +from django import template +from django.template.defaultfilters import linebreaks +from django.template.defaultfilters import safe +from django.template.defaultfilters import slugify +from django.utils.encoding import force_unicode +from django.utils.importlib import import_module +from django.utils.translation import ugettext_lazy as _ + +# FIXME: TableStep +from django.utils.datastructures import SortedDict + +from horizon import base +from horizon import exceptions +from horizon.templatetags.horizon import has_permissions +from horizon.utils import html + + +LOG = logging.getLogger(__name__) + + +class WorkflowContext(dict): + def __init__(self, workflow, *args, **kwargs): + super(WorkflowContext, self).__init__(*args, **kwargs) + self._workflow = workflow + + def __setitem__(self, key, val): + super(WorkflowContext, self).__setitem__(key, val) + return self._workflow._trigger_handlers(key) + + def __delitem__(self, key): + return self.__setitem__(key, None) + + def set(self, key, val): + return self.__setitem__(key, val) + + def unset(self, key): + return self.__delitem__(key) + + +class ActionMetaclass(forms.forms.DeclarativeFieldsMetaclass): + def __new__(mcs, name, bases, attrs): + # Pop Meta for later processing + opts = attrs.pop("Meta", None) + # Create our new class + cls = super(ActionMetaclass, mcs).__new__(mcs, name, bases, attrs) + # Process options from Meta + cls.name = getattr(opts, "name", name) + cls.slug = getattr(opts, "slug", slugify(name)) + cls.permissions = getattr(opts, "permissions", ()) + cls.progress_message = getattr(opts, + "progress_message", + _("Processing...")) + cls.help_text = getattr(opts, "help_text", "") + cls.help_text_template = getattr(opts, "help_text_template", None) + return cls + + +class Action(forms.Form): + """ + An ``Action`` represents an atomic logical interaction you can have with + the system. This is easier to understand with a conceptual example: in the + context of a "launch instance" workflow, actions would include "naming + the instance", "selecting an image", and ultimately "launching the + instance". + + Because ``Actions`` are always interactive, they always provide form + controls, and thus inherit from Django's ``Form`` class. However, they + have some additional intelligence added to them: + + * ``Actions`` are aware of the permissions required to complete them. + + * ``Actions`` have a meta-level concept of "help text" which is meant to be + displayed in such a way as to give context to the action regardless of + where the action is presented in a site or workflow. + + * ``Actions`` understand how to handle their inputs and produce outputs, + much like :class:`~horizon.forms.SelfHandlingForm` does now. + + ``Action`` classes may define the following attributes in a ``Meta`` + class within them: + + .. attribute:: name + + The verbose name for this action. Defaults to the name of the class. + + .. attribute:: slug + + A semi-unique slug for this action. Defaults to the "slugified" name + of the class. + + .. attribute:: permissions + + A list of permission names which this action requires in order to be + completed. Defaults to an empty list (``[]``). + + .. attribute:: help_text + + A string of simple help text to be displayed alongside the Action's + fields. + + .. attribute:: help_text_template + + A path to a template which contains more complex help text to be + displayed alongside the Action's fields. In conjunction with + :meth:`~horizon.workflows.Action.get_help_text` method you can + customize your help text template to display practically anything. + """ + + __metaclass__ = ActionMetaclass + + def __init__(self, request, context, *args, **kwargs): + if request.method == "POST": + super(Action, self).__init__(request.POST, initial=context) + else: + super(Action, self).__init__(initial=context) + + if not hasattr(self, "handle"): + raise AttributeError("The action %s must define a handle method." + % self.__class__.__name__) + self.request = request + self._populate_choices(request, context) + + def __unicode__(self): + return force_unicode(self.name) + + def __repr__(self): + return "<%s: %s>" % (self.__class__.__name__, self.slug) + + def _populate_choices(self, request, context): + for field_name, bound_field in self.fields.items(): + meth = getattr(self, "populate_%s_choices" % field_name, None) + if meth is not None and callable(meth): + bound_field.choices = meth(request, context) + + def get_help_text(self, extra_context=None): + """ Returns the help text for this step. """ + text = "" + extra_context = extra_context or {} + if self.help_text_template: + tmpl = template.loader.get_template(self.help_text_template) + context = template.RequestContext(self.request, extra_context) + text += tmpl.render(context) + else: + text += linebreaks(force_unicode(self.help_text)) + return safe(text) + + def add_error(self, message): + """ + Adds an error to the Action's Step based on API issues. + """ + self._get_errors()[NON_FIELD_ERRORS] = self.error_class([message]) + + def handle(self, request, context): + """ + Handles any requisite processing for this action. The method should + return either ``None`` or a dictionary of data to be passed to + :meth:`~horizon.workflows.Step.contribute`. + + Returns ``None`` by default, effectively making it a no-op. + """ + return None + + +class Step(object): + """ + A step is a wrapper around an action which defines it's context in a + workflow. It knows about details such as: + + * The workflow's context data (data passed from step to step). + + * The data which must be present in the context to begin this step (the + step's dependencies). + + * The keys which will be added to the context data upon completion of the + step. + + * The connections between this step's fields and changes in the context + data (e.g. if that piece of data changes, what needs to be updated in + this step). + + A ``Step`` class has the following attributes: + + .. attribute:: action + + The :class:`~horizon.workflows.Action` class which this step wraps. + + .. attribute:: depends_on + + A list of context data keys which this step requires in order to + begin interaction. + + .. attribute:: contributes + + A list of keys which this step will contribute to the workflow's + context data. Optional keys should still be listed, even if their + values may be set to ``None``. + + .. attribute:: connections + + A dictionary which maps context data key names to lists of callbacks. + The callbacks may be functions, dotted python paths to functions + which may be imported, or dotted strings beginning with ``"self"`` + to indicate methods on the current ``Step`` instance. + + .. attribute:: before + + Another ``Step`` class. This optional attribute is used to provide + control over workflow ordering when steps are dynamically added to + workflows. The workflow mechanism will attempt to place the current + step before the step specified in the attribute. + + .. attribute:: after + + Another ``Step`` class. This attribute has the same purpose as + :meth:`~horizon.workflows.Step.before` except that it will instead + attempt to place the current step after the given step. + + .. attribute:: help_text + + A string of simple help text which will be prepended to the ``Action`` + class' help text if desired. + + .. attribute:: template_name + + A path to a template which will be used to render this step. In + general the default common template should be used. Default: + ``"horizon/common/_workflow_step.html"``. + + .. attribute:: has_errors + + A boolean value which indicates whether or not this step has any + errors on the action within it or in the scope of the workflow. This + attribute will only accurately reflect this status after validation + has occurred. + + .. attribute:: slug + + Inherited from the ``Action`` class. + + .. attribute:: name + + Inherited from the ``Action`` class. + + .. attribute:: permissions + + Inherited from the ``Action`` class. + """ + action_class = None + depends_on = () + contributes = () + connections = None + before = None + after = None + help_text = "" + template_name = "horizon/common/_workflow_step.html" + + def __repr__(self): + return "<%s: %s>" % (self.__class__.__name__, self.slug) + + def __unicode__(self): + return force_unicode(self.name) + + def __init__(self, workflow): + super(Step, self).__init__() + self.workflow = workflow + + cls = self.__class__.__name__ + if not (self.action_class and issubclass(self.action_class, Action)): + raise AttributeError("You must specify an action for %s." % cls) + + self.slug = self.action_class.slug + self.name = self.action_class.name + self.permissions = self.action_class.permissions + self.has_errors = False + self._handlers = {} + + if self.connections is None: + # We want a dict, but don't want to declare a mutable type on the + # class directly. + self.connections = {} + + # Gather our connection handlers and make sure they exist. + for key, handlers in self.connections.items(): + self._handlers[key] = [] + # TODO(gabriel): This is a poor substitute for broader handling + if not isinstance(handlers, (list, tuple)): + raise TypeError("The connection handlers for %s must be a " + "list or tuple." % cls) + for possible_handler in handlers: + if callable(possible_handler): + # If it's callable we know the function exists and is valid + self._handlers[key].append(possible_handler) + continue + elif not isinstance(possible_handler, basestring): + return TypeError("Connection handlers must be either " + "callables or strings.") + bits = possible_handler.split(".") + if bits[0] == "self": + root = self + for bit in bits[1:]: + try: + root = getattr(root, bit) + except AttributeError: + raise AttributeError("The connection handler %s " + "could not be found on %s." + % (possible_handler, cls)) + handler = root + elif len(bits) == 1: + # Import by name from local module not supported + raise ValueError("Importing a local function as a string " + "is not supported for the connection " + "handler %s on %s." + % (possible_handler, cls)) + else: + # Try a general import + module_name = ".".join(bits[:-1]) + try: + mod = import_module(module_name) + handler = getattr(mod, bits[-1]) + except ImportError: + raise ImportError("Could not import %s from the " + "module %s as a connection " + "handler on %s." + % (bits[-1], module_name, cls)) + except AttributeError: + raise AttributeError("Could not import %s from the " + "module %s as a connection " + "handler on %s." + % (bits[-1], module_name, cls)) + self._handlers[key].append(handler) + + @property + def action(self): + if not getattr(self, "_action", None): + try: + # Hook in the action context customization. + workflow_context = dict(self.workflow.context) + context = self.prepare_action_context(self.workflow.request, + workflow_context) + self._action = self.action_class(self.workflow.request, + context) + except: + LOG.exception("Problem instantiating action class.") + raise + return self._action + + def prepare_action_context(self, request, context): + """ + Allows for customization of how the workflow context is passed to the + action; this is the reverse of what "contribute" does to make the + action outputs sane for the workflow. Changes to the context are not + saved globally here. They are localized to the action. + + Simply returns the unaltered context by default. + """ + return context + + def get_id(self): + """ Returns the ID for this step. Suitable for use in HTML markup. """ + return "%s__%s" % (self.workflow.slug, self.slug) + + def _verify_contributions(self, context): + for key in self.contributes: + # Make sure we don't skip steps based on weird behavior of + # POST query dicts. + field = self.action.fields.get(key, None) + if field and field.required and not context.get(key): + context.pop(key, None) + failed_to_contribute = set(self.contributes) + failed_to_contribute -= set(context.keys()) + if failed_to_contribute: + raise exceptions.WorkflowError("The following expected data was " + "not added to the workflow context " + "by the step %s: %s." + % (self.__class__, + failed_to_contribute)) + return True + + def contribute(self, data, context): + """ + Adds the data listed in ``contributes`` to the workflow's shared + context. By default, the context is simply updated with all the data + returned by the action. + + Note that even if the value of one of the ``contributes`` keys is + not present (e.g. optional) the key should still be added to the + context with a value of ``None``. + """ + if data: + for key in self.contributes: + context[key] = data.get(key, None) + return context + + def render(self): + """ Renders the step. """ + step_template = template.loader.get_template(self.template_name) + extra_context = {"form": self.action, + "step": self} + + # FIXME: TableStep: + if issubclass(self.__class__, TableStep): + extra_context.update(self.get_context_data(self.workflow.request)) + + context = template.RequestContext(self.workflow.request, extra_context) + return step_template.render(context) + + def get_help_text(self): + """ Returns the help text for this step. """ + text = linebreaks(force_unicode(self.help_text)) + text += self.action.get_help_text() + return safe(text) + + def add_error(self, message): + """ + Adds an error to the Step based on API issues. + """ + self.action.add_error(message) + + +# FIXME: TableStep +class TableStep(Step): + """ + A :class:`~horizon.workflows.Step` class which knows how to deal with + :class:`~horizon.tables.DataTable` classes rendered inside of it. + + This distinct class is required due to the complexity involved in handling + both dynamic tab loading, dynamic table updating and table actions all + within one view. + + .. attribute:: table_classes + + An iterable containing the :class:`~horizon.tables.DataTable` classes + which this tab will contain. Equivalent to the + :attr:`~horizon.tables.MultiTableView.table_classes` attribute on + :class:`~horizon.tables.MultiTableView`. For each table class you + need to define a corresponding ``get_{{ table_name }}_data`` method + as with :class:`~horizon.tables.MultiTableView`. + """ + + table_classes = None + + def __init__(self, workflow): + super(TableStep, self).__init__(workflow) + if not self.table_classes: + class_name = self.__class__.__name__ + raise NotImplementedError("You must define a table_class " + "attribute on %s" % class_name) + # Instantiate our table classes but don't assign data yet + table_instances = [(table._meta.name, + table(workflow.request, needs_form_wrapper=False)) + for table in self.table_classes] + self._tables = SortedDict(table_instances) + self._table_data_loaded = False + + def load_table_data(self): + """ + Calls the ``get_{{ table_name }}_data`` methods for each table class + and sets the data on the tables. + """ + # We only want the data to be loaded once, so we track if we have... + if not self._table_data_loaded: + for table_name, table in self._tables.items(): + # Fetch the data function. + func_name = "get_%s_data" % table_name + data_func = getattr(self, func_name, None) + if data_func is None: + cls_name = self.__class__.__name__ + raise NotImplementedError("You must define a %s method " + "on %s." % (func_name, cls_name)) + # Load the data. + table.data = data_func() + table._meta.has_more_data = self.has_more_data(table) + # Mark our data as loaded so we don't run the loaders again. + self._table_data_loaded = True + + def get_context_data(self, request): + """ + Adds a ``{{ table_name }}_table`` item to the context for each table + in the :attr:`~horizon.tabs.TableTab.table_classes` attribute. + + If only one table class is provided, a shortcut ``table`` context + variable is also added containing the single table. + """ + context = {} + # If the data hasn't been manually loaded before now, + # make certain it's loaded before setting the context. + self.load_table_data() + for table_name, table in self._tables.items(): + # If there's only one table class, add a shortcut name as well. + if len(self.table_classes) == 1: + context["table"] = table + context["%s_table" % table_name] = table + return context + + def has_more_data(self, table): + return False + + +class WorkflowMetaclass(type): + def __new__(mcs, name, bases, attrs): + super(WorkflowMetaclass, mcs).__new__(mcs, name, bases, attrs) + attrs["_cls_registry"] = set([]) + return type.__new__(mcs, name, bases, attrs) + + +class UpdateMembersStep(Step): + """A step that allows a user to add/remove members from a group. + + .. attribute:: show_roles + + Set to False to disable the display of the roles dropdown. + + .. attribute:: available_list_title + + The title used for the available list column. + + .. attribute:: members_list_title + + The title used for the members list column. + + .. attribute:: no_available_text + + The placeholder text used when the available list is empty. + + .. attribute:: no_members_text + + The placeholder text used when the members list is empty. + + """ + template_name = "horizon/common/_workflow_step_update_members.html" + show_roles = True + available_list_title = _("All available") + members_list_title = _("Members") + no_available_text = _("None available.") + no_members_text = _("No members.") + + +class Workflow(html.HTMLElement): + """ + A Workflow is a collection of Steps. It's interface is very + straightforward, but it is responsible for handling some very + important tasks such as: + + * Handling the injection, removal, and ordering of arbitrary steps. + + * Determining if the workflow can be completed by a given user at runtime + based on all available information. + + * Dispatching connections between steps to ensure that when context data + changes all the applicable callback functions are executed. + + * Verifying/validating the overall data integrity and subsequently + triggering the final method to complete the workflow. + + The ``Workflow`` class has the following attributes: + + .. attribute:: name + + The verbose name for this workflow which will be displayed to the user. + Defaults to the class name. + + .. attribute:: slug + + The unique slug for this workflow. Required. + + .. attribute:: steps + + Read-only access to the final ordered set of step instances for + this workflow. + + .. attribute:: default_steps + + A list of :class:`~horizon.workflows.Step` classes which serve as the + starting point for this workflow's ordered steps. Defaults to an empty + list (``[]``). + + .. attribute:: finalize_button_name + + The name which will appear on the submit button for the workflow's + form. Defaults to ``"Save"``. + + .. attribute:: success_message + + A string which will be displayed to the user upon successful completion + of the workflow. Defaults to + ``"{{ workflow.name }} completed successfully."`` + + .. attribute:: failure_message + + A string which will be displayed to the user upon failure to complete + the workflow. Defaults to ``"{{ workflow.name }} did not complete."`` + + .. attribute:: depends_on + + A roll-up list of all the ``depends_on`` values compiled from the + workflow's steps. + + .. attribute:: contributions + + A roll-up list of all the ``contributes`` values compiled from the + workflow's steps. + + .. attribute:: template_name + + Path to the template which should be used to render this workflow. + In general the default common template should be used. Default: + ``"horizon/common/_workflow.html"``. + + .. attribute:: entry_point + + The slug of the step which should initially be active when the + workflow is rendered. This can be passed in upon initialization of + the workflow, or set anytime after initialization but before calling + either ``get_entry_point`` or ``render``. + + .. attribute:: redirect_param_name + + The name of a parameter used for tracking the URL to redirect to upon + completion of the workflow. Defaults to ``"next"``. + + .. attribute:: object + + The object (if any) which this workflow relates to. In the case of + a workflow which creates a new resource the object would be the created + resource after the relevant creation steps have been undertaken. In + the case of a workflow which updates a resource it would be the + resource being updated after it has been retrieved. + + """ + __metaclass__ = WorkflowMetaclass + slug = None + default_steps = () + template_name = "horizon/common/_workflow.html" + finalize_button_name = _("Save") + success_message = _("%s completed successfully.") + failure_message = _("%s did not complete.") + redirect_param_name = "next" + multipart = False + _registerable_class = Step + + def __unicode__(self): + return self.name + + def __repr__(self): + return "<%s: %s>" % (self.__class__.__name__, self.slug) + + def __init__(self, request=None, context_seed=None, entry_point=None, + *args, **kwargs): + super(Workflow, self).__init__(*args, **kwargs) + if self.slug is None: + raise AttributeError("The workflow %s must have a slug." + % self.__class__.__name__) + self.name = getattr(self, "name", self.__class__.__name__) + self.request = request + self.depends_on = set([]) + self.contributions = set([]) + self.entry_point = entry_point + self.object = None + + # Put together our steps in order. Note that we pre-register + # non-default steps so that we can identify them and subsequently + # insert them in order correctly. + self._registry = dict([(step_class, step_class(self)) for step_class + in self.__class__._cls_registry + if step_class not in self.default_steps]) + self._gather_steps() + + # Determine all the context data we need to end up with. + for step in self.steps: + self.depends_on = self.depends_on | set(step.depends_on) + self.contributions = self.contributions | set(step.contributes) + + # Initialize our context. For ease we can preseed it with a + # regular dictionary. This should happen after steps have been + # registered and ordered. + self.context = WorkflowContext(self) + context_seed = context_seed or {} + clean_seed = dict([(key, val) + for key, val in context_seed.items() + if key in self.contributions | self.depends_on]) + self.context_seed = clean_seed + self.context.update(clean_seed) + + if request and request.method == "POST": + for step in self.steps: + valid = step.action.is_valid() + # Be sure to use the CLEANED data if the workflow is valid. + if valid: + data = step.action.cleaned_data + else: + data = request.POST + self.context = step.contribute(data, self.context) + + @property + def steps(self): + if getattr(self, "_ordered_steps", None) is None: + self._gather_steps() + return self._ordered_steps + + def get_step(self, slug): + """ Returns the instantiated step matching the given slug. """ + for step in self.steps: + if step.slug == slug: + return step + + def _gather_steps(self): + ordered_step_classes = self._order_steps() + for default_step in self.default_steps: + self.register(default_step) + self._registry[default_step] = default_step(self) + self._ordered_steps = [self._registry[step_class] + for step_class in ordered_step_classes + if has_permissions(self.request.user, + self._registry[step_class])] + + def _order_steps(self): + steps = list(copy.copy(self.default_steps)) + additional = self._registry.keys() + for step in additional: + try: + min_pos = steps.index(step.after) + except ValueError: + min_pos = 0 + try: + max_pos = steps.index(step.before) + except ValueError: + max_pos = len(steps) + if min_pos > max_pos: + raise exceptions.WorkflowError("The step %(new)s can't be " + "placed between the steps " + "%(after)s and %(before)s; the " + "step %(before)s comes before " + "%(after)s." + % {"new": additional, + "after": step.after, + "before": step.before}) + steps.insert(max_pos, step) + return steps + + def get_entry_point(self): + """ + Returns the slug of the step which the workflow should begin on. + + This method takes into account both already-available data and errors + within the steps. + """ + # If we have a valid specified entry point, use it. + if self.entry_point: + if self.get_step(self.entry_point): + return self.entry_point + # Otherwise fall back to calculating the appropriate entry point. + for step in self.steps: + if step.has_errors: + return step.slug + try: + step._verify_contributions(self.context) + except exceptions.WorkflowError: + return step.slug + # If nothing else, just return the first step. + return self.steps[0].slug + + def _trigger_handlers(self, key): + responses = [] + handlers = [(step.slug, f) for step in self.steps + for f in step._handlers.get(key, [])] + for slug, handler in handlers: + responses.append((slug, handler(self.request, self.context))) + return responses + + @classmethod + def register(cls, step_class): + """ Registers a :class:`~horizon.workflows.Step` with the workflow. """ + if not inspect.isclass(step_class): + raise ValueError('Only classes may be registered.') + elif not issubclass(step_class, cls._registerable_class): + raise ValueError('Only %s classes or subclasses may be registered.' + % cls._registerable_class.__name__) + if step_class in cls._cls_registry: + return False + else: + cls._cls_registry.add(step_class) + return True + + @classmethod + def unregister(cls, step_class): + """ + Unregisters a :class:`~horizon.workflows.Step` from the workflow. + """ + try: + cls._cls_registry.remove(step_class) + except KeyError: + raise base.NotRegistered('%s is not registered' % cls) + return cls._unregister(step_class) + + def validate(self, context): + """ + Hook for custom context data validation. Should return a boolean + value or raise :class:`~horizon.exceptions.WorkflowValidationError`. + """ + return True + + def is_valid(self): + """ + Verified that all required data is present in the context and + calls the ``validate`` method to allow for finer-grained checks + on the context data. + """ + missing = self.depends_on - set(self.context.keys()) + if missing: + raise exceptions.WorkflowValidationError( + "Unable to complete the workflow. The values %s are " + "required but not present." % ", ".join(missing)) + + # Validate each step. Cycle through all of them to catch all errors + # in one pass before returning. + steps_valid = True + for step in self.steps: + if not step.action.is_valid(): + steps_valid = False + step.has_errors = True + if not steps_valid: + return steps_valid + return self.validate(self.context) + + def finalize(self): + """ + Finalizes a workflow by running through all the actions in order + and calling their ``handle`` methods. Returns ``True`` on full success, + or ``False`` for a partial success, e.g. there were non-critical + errors. (If it failed completely the function wouldn't return.) + """ + partial = False + for step in self.steps: + try: + data = step.action.handle(self.request, self.context) + if data is True or data is None: + continue + elif data is False: + partial = True + else: + self.context = step.contribute(data or {}, self.context) + except: + partial = True + exceptions.handle(self.request) + if not self.handle(self.request, self.context): + partial = True + return not partial + + def handle(self, request, context): + """ + Handles any final processing for this workflow. Should return a boolean + value indicating success. + """ + return True + + def get_success_url(self): + """ + Returns a URL to redirect the user to upon completion. By default it + will attempt to parse a ``success_url`` attribute on the workflow, + which can take the form of a reversible URL pattern name, or a + standard HTTP URL. + """ + try: + return urlresolvers.reverse(self.success_url) + except urlresolvers.NoReverseMatch: + return self.success_url + + def format_status_message(self, message): + """ + Hook to allow customization of the message returned to the user + upon successful or unsuccessful completion of the workflow. + + By default it simply inserts the workflow's name into the message + string. + """ + if "%s" in message: + return message % self.name + else: + return message + + def render(self): + """ Renders the workflow. """ + workflow_template = template.loader.get_template(self.template_name) + extra_context = {"workflow": self} + if self.request.is_ajax(): + extra_context['modal'] = True + context = template.RequestContext(self.request, extra_context) + return workflow_template.render(context) + + def get_absolute_url(self): + """ Returns the canonical URL for this workflow. + + This is used for the POST action attribute on the form element + wrapping the workflow. + + For convenience it defaults to the value of + ``request.get_full_path()`` with any query string stripped off, + e.g. the path at which the workflow was requested. + """ + return self.request.get_full_path().partition('?')[0] + + def add_error_to_step(self, message, slug): + """ + Adds an error to the workflow's Step with the + specifed slug based on API issues. This is useful + when you wish for API errors to appear as errors on + the form rather than using the messages framework. + """ + step = self.get_step(slug) + if step: + step.add_error(message) |