Source code for abilian.web.views.registry

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

import inspect
from operator import attrgetter, itemgetter

from flask import url_for, Blueprint
from whoosh.searching import Hit

from abilian.core.extensions import db


[docs]class Registry(object): """ Registry for default (canonical) views for entities. There is one registry per application instance. """ def __init__(self, *args, **kwargs): self._map = dict()
[docs] def register(self, entity, url_func): """ Associates a `url_func` with entity's type. :param:entity: an :class:`abilian.core.extensions.db.Model` class or instance. :param:url_func: any callable that accepts an entity instance and return an url for it. """ if not inspect.isclass(entity): entity = entity.__class__ assert issubclass(entity, db.Model) self._map[entity.entity_type] = url_func
[docs] def url_for(self, entity=None, object_type=None, object_id=None, **kwargs): """ Returns canonical view for given entity instance. If no view has been registered the registry will try to find an endpoint named with entity's class lowercased followed by '.view' and that accepts `object_id=entity.id` to generates an url. :param entity: a instance of a subclass of :class:`abilian.core.extensions.db.Model`, :class:`whoosh.searching.Hit` or :class:`python:dict` :param object_id: if `entity` is not an instance, this parameter must be set to target id. This is usefull when you know the type and id of an object but don't want to retrieve it from DB. :raise KeyError: if no view can be found for the given entity. """ if object_type is None: assert isinstance(entity, (db.Model, Hit, dict)) getter = attrgetter if isinstance(entity, db.Model) else itemgetter object_id = getter('id')(entity) object_type = getter('object_type')(entity) url_func = self._map.get(object_type) if url_func is not None: return url_func(entity, object_type, object_id, **kwargs) try: return url_for('{}.view'.format(object_type.rsplit('.')[-1].lower()), object_id=object_id, **kwargs) except: raise KeyError(object_type)
[docs]class default_view(object): """ Decorator to register a view as default view for given entity class. :param id_attr: url parameter name for object id. :param endpoint: endpoint to use, defaults to view function's name. :param kw_func: function to process keywords to be passed to url_for. Useful for additional keywords. This function receives: kw, obj, obj_type, obj_id, \*\*kwargs. It must return kw. """ def __init__(self, app_or_blueprint, entity, id_attr='object_id', endpoint=None, kw_func=None): self.app_or_blueprint = app_or_blueprint self.is_bp = isinstance(app_or_blueprint, Blueprint) self.entity = entity self.id_attr = id_attr self.endpoint = endpoint self.kw_func = kw_func def __call__(self, view): endpoint = self.endpoint if endpoint is None: endpoint = view.__name__ if self.is_bp: endpoint = '.' + endpoint if endpoint[0] == '.': endpoint = self.app_or_blueprint.name + endpoint def default_url(obj, obj_type, obj_id, **kwargs): kw = {} kw.update(kwargs) if self.id_attr is not None: # some objects have url with GET parameters only kw[self.id_attr] = obj_id if self.kw_func: kw = self.kw_func(kw, obj, obj_type, obj_id, **kwargs) return url_for(endpoint, **kw) if self.is_bp: @self.app_or_blueprint.record_once def set_default_view(state): state.app.default_view.register(self.entity, default_url) else: self.app_or_blueprint.default_view.register(self.entity, default_url) return view