"""Base class for dynamically loaded objects manipulated in the web interface
:organization: Logilab
:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
"""
__docformat__ = "restructuredtext en"
from datetime import datetime, timedelta
from simplejson import dumps
from logilab.common.decorators import classproperty
from logilab.common.deprecation import obsolete
from rql.nodes import VariableRef, SubQuery
from rql.stmts import Union, Select
from cubicweb import Unauthorized, NoSelectableObject
from cubicweb.vregistry import VObject, AndSelector
from cubicweb.selectors import yes
from cubicweb.utils import UStringIO, ustrftime
ONESECOND = timedelta(0, 1, 0)
class Cache(dict):
def __init__(self):
super(Cache, self).__init__()
self.cache_creation_date = None
self.latest_cache_lookup = datetime.now()
CACHE_REGISTRY = {}
class AppRsetObject(VObject):
"""This is the base class for CubicWeb application objects
which are selected according to a request and result set.
Classes are kept in the vregistry and instantiation is done at selection
time.
At registration time, the following attributes are set on the class:
:vreg:
the application's registry
:schema:
the application's schema
:config:
the application's configuration
At instantiation time, the following attributes are set on the instance:
:req:
current request
:rset:
result set on which the object is applied
"""
__select__ = yes()
@classmethod
def registered(cls, vreg):
super(AppRsetObject, cls).registered(vreg)
cls.vreg = vreg
cls.schema = vreg.schema
cls.config = vreg.config
cls.register_properties()
return cls
@classmethod
def vreg_initialization_completed(cls):
pass
@classmethod
def selected(cls, *args, **kwargs):
"""by default web app objects are usually instantiated on
selection according to a request, a result set, and optional
row and col
"""
assert len(args) <= 2
return cls(*args, **kwargs)
# Eproperties definition:
# key: id of the property (the actual CWProperty key is build using
# <registry name>.<obj id>.<property id>
# value: tuple (property type, vocabfunc, default value, property description)
# possible types are those used by `logilab.common.configuration`
#
# notice that when it exists multiple objects with the same id (adaptation,
# overriding) only the first encountered definition is considered, so those
# objects can't try to have different default values for instance.
property_defs = {}
@classmethod
def register_properties(cls):
for propid, pdef in cls.property_defs.items():
pdef = pdef.copy() # may be shared
pdef['default'] = getattr(cls, propid, pdef['default'])
pdef['sitewide'] = getattr(cls, 'site_wide', pdef.get('sitewide'))
cls.vreg.register_property(cls.propkey(propid), **pdef)
@classmethod
def propkey(cls, propid):
return '%s.%s.%s' % (cls.__registry__, cls.id, propid)
@classproperty
@obsolete('use __select__ and & or | operators')
def __selectors__(cls):
selector = cls.__select__
if isinstance(selector, AndSelector):
return tuple(selector.selectors)
if not isinstance(selector, tuple):
selector = (selector,)
return selector
def __init__(self, req=None, rset=None, row=None, col=None, **extra):
super(AppRsetObject, self).__init__()
self.req = req
self.rset = rset
self.row = row
self.col = col
self.extra_kwargs = extra
def get_cache(self, cachename):
"""
NOTE: cachename should be dotted names as in :
- cubicweb.mycache
- cubes.blog.mycache
- etc.
"""
if cachename in CACHE_REGISTRY:
cache = CACHE_REGISTRY[cachename]
else:
cache = Cache()
CACHE_REGISTRY[cachename] = cache
_now = datetime.now()
if _now > cache.latest_cache_lookup + ONESECOND:
ecache = self.req.execute('Any C,T WHERE C is CWCache, C name %(name)s, C timestamp T',
{'name':cachename}).get_entity(0,0)
cache.latest_cache_lookup = _now
if not ecache.valid(cache.cache_creation_date):
cache.clear()
cache.cache_creation_date = _now
return cache
def propval(self, propid):
assert self.req
return self.req.property_value(self.propkey(propid))
def limited_rql(self):
"""return a printable rql for the result set associated to the object,
with limit/offset correctly set according to maximum page size and
currently displayed page when necessary
"""
# try to get page boundaries from the navigation component
# XXX we should probably not have a ref to this component here (eg in
# cubicweb.common)
nav = self.vreg.select_component('navigation', self.req, self.rset)
if nav:
start, stop = nav.page_boundaries()
rql = self._limit_offset_rql(stop - start, start)
# result set may have be limited manually in which case navigation won't
# apply
elif self.rset.limited:
rql = self._limit_offset_rql(*self.rset.limited)
# navigation component doesn't apply and rset has not been limited, no
# need to limit query
else:
rql = self.rset.printable_rql()
return rql
def _limit_offset_rql(self, limit, offset):
rqlst = self.rset.syntax_tree()
if len(rqlst.children) == 1:
select = rqlst.children[0]
olimit, ooffset = select.limit, select.offset
select.limit, select.offset = limit, offset
rql = rqlst.as_string(kwargs=self.rset.args)
# restore original limit/offset
select.limit, select.offset = olimit, ooffset
else:
newselect = Select()
newselect.limit = limit
newselect.offset = offset
aliases = [VariableRef(newselect.get_variable(vref.name, i))
for i, vref in enumerate(rqlst.selection)]
newselect.set_with([SubQuery(aliases, rqlst)], check=False)
newunion = Union()
newunion.append(newselect)
rql = rqlst.as_string(kwargs=self.rset.args)
rqlst.parent = None
return rql
def view(self, __vid, rset=None, __fallback_vid=None, **kwargs):
"""shortcut to self.vreg.render method avoiding to pass self.req"""
try:
view = self.vreg.select_view(__vid, self.req, rset, **kwargs)
except NoSelectableObject:
if __fallback_vid is None:
raise
view = self.vreg.select_view(__fallback_vid, self.req, rset, **kwargs)
return view.dispatch(**kwargs)
# url generation methods ##################################################
controller = 'view'
def build_url(self, method=None, **kwargs):
"""return an absolute URL using params dictionary key/values as URL
parameters. Values are automatically URL quoted, and the
publishing method to use may be specified or will be guessed.
"""
# XXX I (adim) think that if method is passed explicitly, we should
# not try to process it and directly call req.build_url()
if method is None:
method = self.controller
if method == 'view' and self.req.from_controller() == 'view' and \
not '_restpath' in kwargs:
method = self.req.relative_path(includeparams=False) or 'view'
return self.req.build_url(method, **kwargs)
# various resources accessors #############################################
def entity(self, row, col=0):
"""short cut to get an entity instance for a particular row/column
(col default to 0)
"""
return self.rset.get_entity(row, col)
def complete_entity(self, row, col=0, skip_bytes=True):
"""short cut to get an completed entity instance for a particular
row (all instance's attributes have been fetched)
"""
entity = self.entity(row, col)
entity.complete(skip_bytes=skip_bytes)
return entity
def user_rql_callback(self, args, msg=None):
"""register a user callback to execute some rql query and return an url
to call it ready to be inserted in html
"""
def rqlexec(req, rql, args=None, key=None):
req.execute(rql, args, key)
return self.user_callback(rqlexec, args, msg)
def user_callback(self, cb, args, msg=None, nonify=False):
"""register the given user callback and return an url to call it ready to be
inserted in html
"""
self.req.add_js('cubicweb.ajax.js')
cbname = self.req.register_onetime_callback(cb, *args)
msg = dumps(msg or '')
return "javascript:userCallbackThenReloadPage('%s', %s)" % (
cbname, msg)
# formating methods #######################################################
def tal_render(self, template, variables):
"""render a precompiled page template with variables in the given
dictionary as context
"""
from cubicweb.common.tal import CubicWebContext
context = CubicWebContext()
context.update({'self': self, 'rset': self.rset, '_' : self.req._,
'req': self.req, 'user': self.req.user})
context.update(variables)
output = UStringIO()
template.expand(context, output)
return output.getvalue()
def format_date(self, date, date_format=None, time=False):
"""return a string for a date time according to application's
configuration
"""
if date:
if date_format is None:
if time:
date_format = self.req.property_value('ui.datetime-format')
else:
date_format = self.req.property_value('ui.date-format')
return ustrftime(date, date_format)
return u''
def format_time(self, time):
"""return a string for a time according to application's
configuration
"""
if time:
return ustrftime(time, self.req.property_value('ui.time-format'))
return u''
def format_float(self, num):
"""return a string for floating point number according to application's
configuration
"""
if num:
return self.req.property_value('ui.float-format') % num
return u''
# security related methods ################################################
def ensure_ro_rql(self, rql):
"""raise an exception if the given rql is not a select query"""
first = rql.split(' ', 1)[0].lower()
if first in ('insert', 'set', 'delete'):
raise Unauthorized(self.req._('only select queries are authorized'))
class AppObject(AppRsetObject):
"""base class for application objects which are not selected
according to a result set, only by their identifier.
Those objects may not have req, rset and cursor set.
"""
@classmethod
def selected(cls, *args, **kwargs):
"""by default web app objects are usually instantiated on
selection
"""
return cls(*args, **kwargs)
def __init__(self, req=None, rset=None, **kwargs):
self.req = req
self.rset = rset
self.__dict__.update(kwargs)