Source code for abilian.web.action

# coding=utf-8
from __future__ import absolute_import, print_function, division

import logging
import re
from jinja2 import Template, Markup
from flask import current_app, g
from flask.signals import appcontext_pushed

from abilian.web.util import url_for
from abilian.core.singleton import UniqueName

log = logging.getLogger(__name__)

__all__ = ('Action', 'ModalActionMixin', 'actions')

class Status(UniqueName):
  Action UI status names

#: default action status: show in UID, usable, not marked "current"
ENABLED = Status(u'enabled')
#: action is "active" or "current". For example the current navigation item.
ACTIVE = Status(u'active')
#: action should be shown in a disabled state
DISABLED = Status(u'disabled')

def getset(f):
  Shortcut for a custom getter/ standard setter.

      def my_property(self, value=None):
          if value is None:
              return getter_value

  Default value for `value` should be any marker that helps distinguish
  between getter or setter mode. If None is not appropriate a good approach is
  to use a unique object instance::

      MARK = object()
      # test like this
      if value is MARK:
        # getter mode
  return property(f, f)

class Icon(object):
  Base abstract class for icons
  def __html__(self):
    raise NotImplementedError

  def __unicode__(self):
    return self.__html__()

class NamedIconBase(Icon):
  Renders markup for named icons set
  template = None

  def __init__(self, name=u''): = name

  def __html__(self):
    return self.template.render(

class Glyphicon(NamedIconBase):
  Renders markup for bootstrap's glyphicons
  template = Template(u'<i class="glyphicon glyphicon-{{ name }}"></i>')

class FAIcon(NamedIconBase):
  Renders markup for FontAwesome icons
  template = Template(u'<i class="fa fa-{{ name }}"></i>')

class DynamicIcon(Icon):

  template = Template(u'<img {%- if css %} class="{{ css }}"{% endif %} '
                      u'src="{{ url }}" '
                      u'width="{{ width }}" height="{{ height }}" />')

  def __init__(self, endpoint=None, width=12, height=12, css=u'',
               size=None, url_args=None, **fixed_url_args):
    self.endpoint = endpoint
    self.css = css
    self.fixed_url_args = dict()
    self.url_args_callback = url_args

    if size is not None:
      width = height = size

    self.width = width
    self.height = height

  def get_url_args(self):
    kw = dict()
    return kw

  def __html__(self):
    endpoint = self.endpoint
    if callable(endpoint):
      endpoint = endpoint()

    url_args = self.get_url_args()
    if self.url_args_callback is not None:
      url_args = self.url_args_callback(self, url_args)

    return self.template.render(
      url=url_for(endpoint, **url_args),

class StaticIcon(DynamicIcon):
  Renders markup for icon located in static folder served by `endpoint`.

  Default endpoint is application static folder.
  def __init__(self, filename, endpoint='static', width=12, height=12, css=u'',
    DynamicIcon.__init__(self, endpoint, width, height, css, size,

class Endpoint(object):

  # FIXME: *args doesn't seem to be relevant.
  def __init__(self, name, *args, **kwargs): = name
    self.args = args
    self.kwargs = kwargs

  def get_kwargs(self):
    Hook for subclasses.

    The key and values in the returned dictionnary can be safely changed
    without side effects on self.kwargs (provided you don't alter
    mutable values, like calling list.pop()).
    return self.kwargs.copy()

  def __unicode__(self):
    return unicode(url_for(, *self.args, **self.get_kwargs()))

  def __repr__(self):
    return '{cls}({name!r}, *{args!r}, **{kwargs!r})'.format(

[docs]class Action(object): """ Action interface. """ Endpoint = Endpoint category = None name = None title = None description = None icon = None _url = None CSS_CLASS = u'action action-{category} action-{category}-{name}' #: A :class:`Endpoint` instance, a string for a simple endpoint, a tuple #: ``(endpoint_name, kwargs)`` or a callable which accept a : context dict #: and returns one of those a valid values. endpoint = None #: A boolean (or something that can be converted to boolean), or a callable #: which accepts a context dict as parameter. See :meth:`available`. condition = None template_string = ( u'<a class="{{ action.css_class }}" href="{{ url }}">' u'{%- if action.icon %}{{ action.icon }} {% endif %}' u'{{ action.title }}' u'</a>' ) def __init__(self, category, name, title=None, description=None, icon=None, url=None, endpoint=None, condition=None, status=None, template=None, template_string=None, button=None, css=None): """ :param button: if not `None`, a valid `btn` class (i.e `default`, `primary`...) :param css: additional css class string :param template: optional: a template file name or a list of filenames. :param template_string: template_string to use. Defaults to `Action.template_string` """ self.category = category = name if button is not None: self.CSS_CLASS = self.CSS_CLASS + u' btn btn-{}'.format(button) if css is not None: self.CSS_CLASS = self.CSS_CLASS + u' ' + css self._build_css_class() self.title = title self.description = description if isinstance(icon, basestring): icon = Glyphicon(icon) self.icon = icon self._url = url self._status = Status(status) if status is not None else ENABLED self.endpoint = endpoint if not callable(endpoint) and not isinstance(endpoint, Endpoint): # property getter will make it and Endpoint instance self.endpoint = self.endpoint self.condition = condition self._enabled = True self.template = template if template_string: self.template_string = template_string #: ui status. A :class:`Status` instance @getset def status(self, value=None): status = self._status if value is not None: self._status = status = Status(value) return status #: Boolean. Disabled actions are unconditionnaly skipped. @getset def enabled(self, value=None): enabled = self._enabled if value is not None: assert isinstance(value, bool) self._enabled = enabled = value return enabled def _get_and_call(self, attr): attr = '_' + attr value = getattr(self, attr) if callable(value): value = value(actions.context) return value @property def title(self): return self._get_and_call('title') @title.setter def title(self, title): self._title = title def _build_css_class(self): css_cat = self.CSS_CLASS.format(action=self, category=self.category, css_cat = re.sub(r'[^ _a-zA-Z0-9-]', '-', css_cat) self.css_class = css_cat @property def description(self): return self._get_and_call('description') @description.setter def description(self, description): self._description = description @property def icon(self): return self._get_and_call('icon') @icon.setter def icon(self, icon): self._icon = icon @property def endpoint(self): endpoint = self._get_and_call('endpoint') if endpoint is None: return if not isinstance(endpoint, Endpoint): if isinstance(endpoint, basestring): endpoint = self.Endpoint(endpoint) elif isinstance(endpoint, (tuple, list)): assert len(endpoint) == 2 endpoint, kwargs = endpoint assert isinstance(endpoint, basestring) assert isinstance(kwargs, dict) endpoint = self.Endpoint(endpoint, **kwargs) else: raise ValueError('Invalid endpoint specifier: "%s"' % repr(endpoint)) return endpoint @endpoint.setter def endpoint(self, endpoint): self._endpoint = endpoint
[docs] def available(self, context): """ Determine if this actions is available in this `context`. :param context: a dict whose content is left to application needs; if :attr:`.condition` is a callable it receives `context` in parameter. """ if not self._enabled: return False return self.pre_condition(context) and self._check_condition(context)
[docs] def pre_condition(self, context): """ Called by :meth:`.available` before checking condition. Subclasses may override it to ease creating actions with repetitive check (for example: actions that apply on a given content type only). """ return True
def _check_condition(self, context): if self.condition is None: return True if callable(self.condition): return self.condition(context) else: return bool(self.condition)
[docs] def render(self, **kwargs): if not self.template: self.template = Template(self.template_string) template = self.template if not isinstance(template, Template): template = current_app.jinja_env.get_or_select_template(template) params = self.get_render_args(**kwargs) return Markup(template.render(params))
[docs] def get_render_args(self, **kwargs): params = dict(action=self) params.update(actions.context) params.update(kwargs) params['url'] = self.url(params) return params
[docs] def url(self, context=None): if callable(self._url): return self._url(context) endpoint = self.endpoint if endpoint: return unicode(endpoint) return self._url
[docs]class ModalActionMixin(object): template_string = ( u'<a class="{{ action.css_class }}" href="{{ url }}" data-toggle="modal">' u'{%- if action.icon %}{{ action.icon}} {% endif %}' u'{{ action.title }}' u'</a>' )
class ButtonAction(Action): template_string = ( u'<button type="submit" ' u'class="btn btn-{{ action.btn_class }} {{ action.css_class}}" ' u'name="{{ action.submit_name }}" ' u'value="{{ }}">' u'{%- if action.icon %}{{ action.icon }} {% endif %}' u'{{ action.title }}</button>' ) btn_class = 'default' def __init__(self, category, name, submit_name="__action", btn_class='default', *args, **kwargs): Action.__init__(self, category, name, *args, **kwargs) self.submit_name = submit_name self.btn_class = btn_class class ActionGroup(Action): """ A group of single actions """ template_string = ( u'<div class="btn-group" role="group" aria-label="{{}}">' u'{%- for entry in action_items %}' u'{{ entry.render() }}' u'{%- endfor %}' u'</div>' ) def __init__(self, category, name, items=(), *args, **kwargs): super(ActionGroup, self).__init__(category, name, *args, **kwargs) self.items = list(items) def get_render_args(self, **kwargs): params = super(ActionGroup, self).get_render_args(**kwargs) params['action_items'] = [a for a in self.items if a.available(params)] return params class ActionDropDown(ActionGroup): """ Renders as a button dropdown """ template_string = u''' <div class="btn-group"> <button type="button" class="{{ action.css_class }} dropdown-toggle" data-toggle="dropdown" aria-expanded="false"> {%- if action.icon %}{{ action.icon }} {% endif %} {{ action.title }} <span class="caret"></span> </button> <ul class="dropdown-menu" role="menu"> {%- for entry in action_items %} {%- if entry.divider %}<li class="divider"></li>{%- endif %} <li>{{ entry.render() }}</a> </li> {%- endfor %} </ul> </div> ''' class ActionGroupItem(Action): #: if True, add a divider in dropdowns divider = False def __init__(self, category, name, divider=False, *args, **kwargs): super(ActionGroupItem, self).__init__(category, name, *args, **kwargs) self.divider = divider
[docs]class ActionRegistry(object): """ The Action registry. This is a Flask extension which registers :class:`.Action` sets. Actions are grouped by category and are ordered by registering order. From your application use the instanciated registry :data:`.actions`. The registry is available in jinja2 templates as `actions`. """ __EXTENSION_NAME = 'abilian:actions'
[docs] def init_app(self, app): if self.__EXTENSION_NAME in app.extensions: log.warning('ActionRegistry.init_app: actions already enabled on this application') return app.extensions[self.__EXTENSION_NAME] = dict(categories=dict()) appcontext_pushed.connect(self._init_context, app) @app.context_processor def add_registry_to_jinja_context(): return dict(actions=self)
[docs] def installed(self, app=None): """ Return `True` if the registry has been installed in current applications """ if app is None: app = current_app return self.__EXTENSION_NAME in app.extensions
[docs] def register(self, *actions): """ Register `actions` in the current application. All `actions` must be an instance of :class:`.Action` or one of its subclasses. If `overwrite` is `True`, then it is allowed to overwrite an existing action with same name and category; else `ValueError` is raised. """ assert self.installed(), "Actions not enabled on this application" assert all(map(lambda a: isinstance(a, Action), actions)) for action in actions: cat = action.category reg = self._state['categories'].setdefault(cat, []) reg.append(action)
[docs] def actions(self, context=None): """ Return a mapping of category => actions list. Actions are filtered according to :meth:`.Action.available`. if `context` is None, then current action context is used (:attr:`context`). """ assert self.installed(), "Actions not enabled on this application" result = {} if context is None: context = self.context for cat, actions in self._state['categories'].items(): result[cat] = [a for a in actions if a.available(context)] return result
[docs] def for_category(self, category, context=None): """ Returns actions list for this category in current application. Actions are filtered according to :meth:`.Action.available`. if `context` is None, then current action context is used (:attr:`context`) """ assert self.installed(), "Actions not enabled on this application" actions = self._state['categories'].get(category, []) if context is None: context = self.context return filter(lambda a: a.available(context), actions)
@property def _state(self): return current_app.extensions[self.__EXTENSION_NAME] def _init_context(self, sender): g.action_context = {} @property def context(self): """ Return action context (dict type). Applications can modify it to suit their needs. """ return g.action_context
actions = ActionRegistry()