# -*- coding: utf-8 -*- from __future__ import division __copyright__ = "Copyright (C) 2014 Andreas Kloeckner" __license__ = """ Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. """ from django.shortcuts import ( # noqa render, get_object_or_404) from course.views import ( get_role_and_participation ) from course.content import ( get_course_repo, get_course_desc, get_flow_desc, dict_to_struct, parse_date_spec, get_active_commit_sha) from course.models import ( Course, FlowAccessException, FlowPageVisit, participation_role, flow_permission ) # {{{ flow permissions def get_flow_permissions(course, participation, role, flow_id, flow_desc, now_datetime): # {{{ interpret flow rules flow_rule = None if not hasattr(flow_desc, "access_rules"): flow_rule = dict_to_struct( {"permissions": [flow_permission.view, flow_permission.start_no_credit]}) else: for rule in flow_desc.access_rules: if hasattr(rule, "roles"): if role not in rule.roles: continue if hasattr(rule, "start"): start_date = parse_date_spec(course, rule.start) if now_datetime < start_date: continue if hasattr(rule, "end"): end_date = parse_date_spec(course, rule.end) if end_date < now_datetime: continue flow_rule = rule break # }}} # {{{ scan for exceptions in database for exc in ( FlowAccessException.objects .filter(participation=participation, flow_id=flow_id) .order_by("expiration")): if exc.expiration is not None and exc.expiration < now_datetime: continue exc_stipulations = exc.stipulations if not isinstance(exc_stipulations, dict): exc_stipulations = {} stipulations = {} if flow_rule is not None: stipulations.update( (key, val) for key, val in flow_rule.__dict__.iteritems() if not key.startswith("_")) stipulations.update(exc_stipulations) stipulations = dict_to_struct(stipulations) return ( [entry.permission for entry in exc.entries.all()], stipulations ) # }}} if flow_rule is not None: return flow_rule.permissions, flow_rule raise ValueError("Flow access rules of flow '%s' did not resolve " "to access answer for '%s'" % (flow_id, participation)) def instantiate_flow_page_with_ctx(fctx, page_data): from course.content import get_flow_page_desc page_desc = get_flow_page_desc( fctx.flow_session, fctx.flow_desc, page_data.group_id, page_data.page_id) from course.content import instantiate_flow_page return instantiate_flow_page( "course '%s', flow '%s', page '%s/%s'" % (fctx.course_identifier, fctx.flow_identifier, page_data.group_id, page_data.page_id), fctx.repo, page_desc, fctx.flow_commit_sha) # }}} # {{{ contexts class CoursePageContext(object): def __init__(self, request, course_identifier): self.request = request self.course_identifier = course_identifier self.course = get_object_or_404(Course, identifier=course_identifier) self.role, self.participation = get_role_and_participation( request, self.course) from course.views import check_course_state check_course_state(self.course, self.role) self.course_commit_sha = get_active_commit_sha( self.course, self.participation) self.repo = get_course_repo(self.course) self.course_desc = get_course_desc(self.repo, self.course, self.course_commit_sha) class FlowContext(CoursePageContext): def __init__(self, request, course_identifier, flow_identifier, flow_session=None): CoursePageContext.__init__(self, request, course_identifier) self.flow_session = flow_session self.flow_identifier = flow_identifier from course.content import get_flow_commit_sha from django.core.exceptions import ObjectDoesNotExist # Fetch 'current' version of the flow to compute permissions # and versioning rules. # Fall back to 'old' version if current git version does not # contain this flow any more. try: current_flow_desc_sha = self.course_commit_sha current_flow_desc = get_flow_desc(self.repo, self.course, flow_identifier, current_flow_desc_sha) except ObjectDoesNotExist: current_flow_desc_sha = self.flow_session.active_git_commit_sha.encode() current_flow_desc = get_flow_desc(self.repo, self.course, flow_identifier, current_flow_desc_sha) self.flow_commit_sha = get_flow_commit_sha( self.course, self.participation, current_flow_desc, self.flow_session) if self.flow_commit_sha == current_flow_desc_sha: self.flow_desc = current_flow_desc else: self.flow_desc = get_flow_desc(self.repo, self.course, flow_identifier, self.flow_commit_sha) # {{{ figure out permissions from course.views import get_now_or_fake_time self.permissions, self.stipulations = get_flow_permissions( self.course, self.participation, self.role, flow_identifier, current_flow_desc, get_now_or_fake_time(request)) # }}} def will_receive_feedback(self): from course.models import flow_permission return ( flow_permission.see_correctness in self.permissions or flow_permission.see_answer in self.permissions) @property def page_count(self): return self.flow_session.page_count class FlowPageContext(FlowContext): """This object acts as a container for all the information that a flow page may need to render itself or respond to a POST. """ def __init__(self, request, course_identifier, flow_identifier, ordinal, flow_session): FlowContext.__init__(self, request, course_identifier, flow_identifier, flow_session=flow_session) from course.models import FlowPageData page_data = self.page_data = get_object_or_404( FlowPageData, flow_session=flow_session, ordinal=ordinal) from course.content import get_flow_page_desc self.page_desc = get_flow_page_desc( flow_session, self.flow_desc, page_data.group_id, page_data.page_id) self.page = instantiate_flow_page_with_ctx(self, page_data) from course.page import PageContext self.page_context = PageContext( course=self.course, repo=self.repo, commit_sha=self.flow_commit_sha) # {{{ dig for previous answers previous_answer_visits = (FlowPageVisit.objects .filter(flow_session=flow_session) .filter(page_data=page_data) .filter(answer__isnull=False) .order_by("-visit_time")) self.prev_answer_was_graded = not self.flow_session.in_progress self.prev_answer = None for prev_visit in previous_answer_visits: self.prev_answer = prev_visit.answer self.prev_answer_was_graded = ( prev_visit.is_graded_answer or not self.flow_session.in_progress) break # }}} @property def ordinal(self): return self.page_data.ordinal @property def percentage_done(self): return int(100*(self.ordinal+1)/self.page_count) def create_visit(self, request): page_visit = FlowPageVisit() page_visit.flow_session = self.flow_session page_visit.page_data = self.page_data page_visit.remote_address = request.META['REMOTE_ADDR'] page_visit.save() # }}} def course_view(f): def wrapper(request, course_identifier, *args, **kwargs): pctx = CoursePageContext(request, course_identifier) return f(pctx, *args, **kwargs) from functools import update_wrapper update_wrapper(wrapper, f) return wrapper def render_course_page(pctx, template_name, args): args = args.copy() args.update({ "course": pctx.course, "course_desc": pctx.course_desc, "participation": pctx.participation, "role": pctx.role, "participation_role": participation_role, }) return render(pctx.request, template_name, args) # vim: foldmethod=marker