+
−#!/usr/bin/python2.5
+
−#
+
−# Copyright 2008 the Melange authors.
+
−#
+
−# 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.
+
−
+
−"""Helpers functions for displaying views.
+
−"""
+
−
+
−__authors__ = [
+
−  '"Sverre Rabbelier" <sverre@rabbelier.nl>',
+
−  ]
+
−
+
−
+
−from django import http
+
−from django.utils.translation import ugettext_lazy
+
−
+
−import soc.logic
+
−import soc.logic.dicts
+
−import soc.logic.out_of_band
+
−import soc.views.helper.lists
+
−import soc.views.helper.responses
+
−import soc.views.out_of_band
+
−
+
−from soc.logic import dicts
+
−from soc.logic import models
+
−from soc.views import simple
+
−from soc.views import helper
+
−from soc.views.helper import access
+
−
+
−
+
−class View:
+
−  """Views for entity classes.
+
−
+
−  The View class functions specific to Entity classes by relying
+
−  on the the child-classes to define the following fields:
+
−
+
−  self._logic: the logic singleton for this entity
+
−  """
+
−
+
−  DEF_SUBMIT_MSG_PARAM_NAME = 's'
+
−  DEF_SUBMIT_MSG_PROFILE_SAVED = 0
+
−
+
−  DEF_CREATE_NEW_ENTITY_MSG = ugettext_lazy(
+
−      ' You can create a new %(entity_type_lower)s by visiting'
+
−      ' <a href="%(create)s">Create '
+
−      'a New %(entity_type)s</a> page.')
+
−
+
−  def __init__(self, params=None, rights=None):
+
−    """
+
−
+
−    Args:
+
−      rights: This dictionary should be filled with the access check
+
−        functions that should be called, it will be modified in-place.
+
−      params: This dictionary should be filled with the parameters
+
−        specific to this entity, required fields are:
+
−        name: the name of the entity (names should have sentence-style caps) 
+
−        name_short: the short form name of the name ('org' vs 'organization')
+
−        name_plural: the plural form of the name
+
−        edit_form: the class of the Django form to be used when editing
+
−        create_form: the class of the Django form to be used when creating
+
−        edit_template: the Django template to be used for editing
+
−        public_template: the Django template to be used as public page 
+
−        list_template: the Django template to be used as list page
+
−        lists_template: the Django templates to search for the list page
+
−        delete_redirect: the Django template to redirect to on delete
+
−        create_redirect: the Django template to redirect to after creation
+
−        save_message: the message to display when the entity is saved
+
−        edit_params: the params to use when editing
+
−    """
+
−
+
−    new_rights = {}
+
−    new_rights['any_access'] = [access.checkIsUser]
+
−
+
−    self._rights = dicts.merge(rights, new_rights)
+
−    self._params = params
+
−
+
−  def public(self, request, page=None, **kwargs):
+
−    """Displays the public page for the entity specified by **kwargs
+
−
+
−    Args:
+
−      request: the standard Django HTTP request object
+
−      page: a soc.logic.site.page.Page object which is abstraction
+
−        that combines a Django view with sidebar menu info
+
−      kwargs: the Key Fields for the specified entity
+
−    """
+
−
+
−    try:
+
−      self.checkAccess('public', request)
+
−    except soc.views.out_of_band.AccessViolationResponse, alt_response:
+
−      return alt_response.response()
+
−
+
−    # create default template context for use with any templates
+
−    context = helper.responses.getUniversalContext(request)
+
−    context['page'] = page
+
−    entity = None
+
−
+
−    try:
+
−      entity = self._logic.getIfFields(**kwargs)
+
−    except soc.logic.out_of_band.ErrorResponse, error:
+
−      template = self._params['public_template']
+
−      return simple.errorResponse(request, page, error, template, context)
+
−
+
−    if not entity:
+
−      #TODO: Change this into a proper redirect
+
−      return http.HttpResponseRedirect('/')
+
−
+
−    context['entity'] = entity
+
−    context['entity_type'] = self._params['name']
+
−
+
−    template = self._params['public_template']
+
−
+
−    return helper.responses.respond(request, template, context)
+
−
+
−  def create(self, request, page=None, **kwargs):
+
−    """Displays the create page for this entity type
+
−
+
−    Args:
+
−      request: the standard Django HTTP request object
+
−      page: a soc.logic.site.page.Page object which is abstraction
+
−        that combines a Django view with sidebar menu info
+
−      kwargs: not used for create()
+
−    """
+
−
+
−    # Create page is an edit page with no key fields
+
−    kwargs = {}
+
−    fields = self._logic.getKeyFieldNames()
+
−    for field in fields:
+
−      kwargs[field] = None
+
−
+
−    return self.edit(request, page=page, **kwargs)
+
−
+
−  def edit(self, request, page=None, **kwargs):
+
−    """Displays the public page for the entity specified by **kwargs
+
−
+
−    Args:
+
−      request: the standard Django HTTP request object
+
−      page: a soc.logic.site.page.Page object which is abstraction
+
−        that combines a Django view with sidebar menu info
+
−      kwargs: The Key Fields for the specified entity
+
−    """
+
−
+
−    try:
+
−      self.checkAccess('edit', request)
+
−    except soc.views.out_of_band.AccessViolationResponse, alt_response:
+
−      return alt_response.response()
+
−
+
−    context = helper.responses.getUniversalContext(request)
+
−    context['page'] = page
+
−    entity = None
+
−
+
−    try:
+
−      entity = self._logic.getIfFields(**kwargs)
+
−    except soc.logic.out_of_band.ErrorResponse, error:
+
−      template = self._params['public_template']
+
−      error.message = error.message + self.DEF_CREATE_NEW_ENTITY_MSG % {
+
−          'entity_type_lower' : self._params['name'].lower(),
+
−          'entity_type' : self._params['name'],
+
−          'create' : self._params['create_redirect']
+
−          }
+
−      return simple.errorResponse(request, page, error, template, context)
+
−
+
−    if request.method == 'POST':
+
−      return self.editPost(request, entity, context)
+
−    else:
+
−      return self.editGet(request, entity, context)
+
−
+
−  def editPost(self, request, entity, context):
+
−    """Same as edit, but on POST
+
−    """
+
−
+
−    if entity:
+
−      form = self._params['edit_form'](request.POST)
+
−    else:
+
−      form = self._params['create_form'](request.POST)
+
−
+
−    if not form.is_valid():
+
−      return self._constructResponse(request, entity, context, form)
+
−
+
−    fields = self.collectCleanedFields(form)
+
−
+
−    self._editPost(request, entity, fields)
+
−
+
−    keys = self._logic.getKeyFieldNames()
+
−    values = self._logic.getKeyValuesFromFields(fields)
+
−    kwargs = dicts.zip(keys, values)
+
−    entity = self._logic.updateOrCreateFromFields(fields, **kwargs)
+
−
+
−    if not entity:
+
−      return http.HttpResponseRedirect('/')
+
−
+
−    params = self._params['edit_params']
+
−    suffix = self._logic.getKeySuffix(entity)
+
−
+
−    # redirect to (possibly new) location of the entity
+
−    # (causes 'Profile saved' message to be displayed)
+
−    return helper.responses.redirectToChangedSuffix(
+
−        request, suffix, suffix,
+
−        params=params)
+
−
+
−  def editGet(self, request, entity, context):
+
−    """Same as edit, but on GET
+
−    """
+
−
+
−    suffix = self._logic.getKeySuffix(entity)
+
−
+
−    # Remove the params from the request, this is relevant only if
+
−    # someone bookmarked a POST page.
+
−    is_self_referrer = helper.requests.isReferrerSelf(request, suffix=suffix)
+
−    if request.GET.get(self.DEF_SUBMIT_MSG_PARAM_NAME):
+
−      if (not entity) or (not is_self_referrer):
+
−        return http.HttpResponseRedirect(request.path)
+
−
+
−    if entity:
+
−      # Note: no message will be displayed if parameter is not present
+
−      context['notice'] = helper.requests.getSingleIndexedParamValue(
+
−          request, self.DEF_SUBMIT_MSG_PARAM_NAME,
+
−          values=self._params['save_message'])
+
−
+
−      # populate form with the existing entity
+
−      form = self._params['edit_form'](instance=entity)
+
−      self._editGet(request, entity, form)
+
−    else:
+
−      form = self._params['create_form']()
+
−
+
−    return self._constructResponse(request, entity, context, form)
+
−
+
−  def list(self, request, page=None):
+
−    """Displays the list page for the entity type
+
−    
+
−    Args:
+
−      request: the standard Django HTTP request object
+
−      page: a soc.logic.site.page.Page object which is abstraction
+
−        that combines a Django view with sidebar menu info
+
−    """
+
−
+
−    try:
+
−      self.checkAccess('list', request)
+
−    except soc.views.out_of_band.AccessViolationResponse, alt_response:
+
−      return alt_response.response()
+
−
+
−    context = helper.responses.getUniversalContext(request)
+
−    context['page'] = page
+
−
+
−    offset, limit = helper.lists.cleanListParameters(
+
−      offset=request.GET.get('offset'), limit=request.GET.get('limit'))
+
−
+
−    # Fetch one more to see if there should be a 'next' link
+
−    entities = self._logic.getForLimitAndOffset(limit + 1, offset=offset)
+
−
+
−    context['pagination_form'] = helper.lists.makePaginationForm(request, limit)
+
−
+
−    templates = self._params['lists_template']
+
−
+
−    context = helper.lists.setList(request, context, entities, 
+
−                                 offset, limit, templates)
+
−
+
−    context['entity_type'] = self._params['name']
+
−    context['entity_type_plural'] = self._params['name_plural']
+
−
+
−    template = self._params['list_template']
+
−
+
−    return helper.responses.respond(request, template, context)
+
−
+
−  def delete(self, request, page=None, **kwargs):
+
−    """Shows the delete page for the entity specified by kwargs
+
−
+
−    Args:
+
−      request: the standard Django HTTP request object
+
−      page: a soc.logic.site.page.Page object which is abstraction
+
−        that combines a Django view with sidebar menu info
+
−      kwargs: The Key Fields for the specified entity
+
−    """
+
−
+
−    try:
+
−      self.checkAccess('delete', request)
+
−    except soc.views.out_of_band.AccessViolationResponse, alt_response:
+
−      return alt_response.response()
+
−
+
−    # create default template context for use with any templates
+
−    context = helper.responses.getUniversalContext(request)
+
−    context['page'] = page
+
−    entity = None
+
−
+
−    try:
+
−      entity = self._logic.getIfFields(**kwargs)
+
−    except soc.logic.out_of_band.ErrorResponse, error:
+
−      template = self._params['edit_template']
+
−      error.message = error.message + self.DEF_CREATE_NEW_ENTITY_MSG % {
+
−          'entity_type_lower' : self._params['name'].lower(),
+
−          'entity_type' : self._params['name'],
+
−          'create' : self._params['create_redirect']
+
−          }
+
−      return simple.errorResponse(request, page, error, template, context)
+
−
+
−    if not entity:
+
−      #TODO: Create a proper error page for this
+
−      return http.HttpResponseRedirect('/')
+
−
+
−    if not self._logic.isDeletable(entity):
+
−      # TODO: Update the notice area telling the user that they
+
−      # can't delete the entity
+
−      pass
+
−
+
−    self._logic.delete(entity)
+
−    redirect = self._params['delete_redirect']
+
−
+
−    return http.HttpResponseRedirect(redirect)
+
−
+
−  def _editPost(self, request, entity, fields):
+
−    """Performs any required processing on the entity to post its edit page
+
−
+
−    Args:
+
−      request: the django request object
+
−      entity:  the entity to create or update from POST contents
+
−      fields: the new field values
+
−    """
+
−
+
−    raise NotImplementedError
+
−
+
−  def _editGet(self, request, entity, form):
+
−    """Performs any required processing on the form to get its edit page
+
−
+
−    Args:
+
−      request: the django request object
+
−      entity: the entity to get
+
−      form: the django form that will be used for the page
+
−    """
+
−
+
−    pass
+
−
+
−  def checkUnspecified(self, access_type, request):
+
−    """Checks whether an unspecified access_type should be allowed
+
−
+
−    Args:
+
−      access_type: the access type (such as 'list' or 'edit') that was
+
−                   not present in the _rights dictionary when checking.
+
−    """
+
−
+
−    pass
+
−
+
−  def _constructResponse(self, request, entity, context, form):
+
−    """Updates the context and returns a response for the specified arguments
+
−
+
−    Args:
+
−      request: the django request object
+
−      entity: the entity that is used
+
−      context: the context to be used
+
−      form: the form that will be used
+
−    """
+
−
+
−    suffix = self._logic.getKeySuffix(entity)
+
−
+
−    context['form'] = form
+
−    context['entity'] = entity
+
−    context['entity_suffix'] = suffix
+
−    context['entity_type'] = self._params['name']
+
−    context['entity_type_plural'] = self._params['name_plural']
+
−    context['entity_type_short'] = self._params['name_short']
+
−
+
−    template = self._params['edit_template']
+
−
+
−    return helper.responses.respond(request, template, context)
+
−
+
−  def checkAccess(self, access_type, request):
+
−    """Runs all the defined checks for the specified type
+
−
+
−    Args:
+
−      access_type: the type of request (such as 'list' or 'edit')
+
−      request: the Django request object
+
−
+
−    Returns:
+
−      True: If all the required access checks have been made successfully
+
−      False: If a check failed, in this case self._response will contain
+
−             the response provided by the failed access check.
+
−    """
+
−
+
−    # Call each access checker
+
−    for check in self._rights['any_access']:
+
−      check(request)
+
−
+
−    if access_type not in self._rights:
+
−       # No checks defined, so do the 'generic check' and bail out
+
−      self.checkUnspecified(access_type, request)
+
−      return
+
−
+
−    for check in self._rights[access_type]:
+
−      check(request)
+
−
+
−  def collectCleanedFields(self, form):
+
−    """Collects all cleaned fields from form and returns them 
+
−
+
−    Args:
+
−      form: The form from which the cleaned fields should be collected
+
−    """
+
−
+
−    fields = {}
+
−
+
−    for field, value in form.cleaned_data.iteritems():
+
−      fields[field] = value
+
−
+
−    return fields