# -*- 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, redirect) from django.contrib import messages from django.core.exceptions import PermissionDenied, SuspiciousOperation from django.db import transaction from django.utils.safestring import mark_safe import re from course.models import ( Course, participation_role, FlowAccessException, FlowSession, FlowPageData, FlowPageVisit, flow_permission, GradeChange) from course.content import ( get_course_repo, get_course_desc, get_flow_desc, parse_date_spec ) from course.auth import get_role_and_participation from course.views import check_course_state, get_active_commit_sha from course.content import dict_to_struct 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)) # {{{ start flow class FlowContext(object): def __init__(self, request, course_identifier, flow_identifier, flow_session=None): self.flow_session = flow_session self.course_identifier = course_identifier self.flow_identifier = flow_identifier self.course = get_object_or_404(Course, identifier=course_identifier) self.role, self.participation = get_role_and_participation( request, self.course) check_course_state(self.course, self.role) self.course_commit_sha = get_active_commit_sha( self.course, self.participation) if self.flow_session is not None: self.commit_sha = self.flow_session.active_git_commit_sha.encode() else: self.commit_sha = self.course_commit_sha self.repo = get_course_repo(self.course) self.course_desc = get_course_desc(self.repo, self.course, self.commit_sha) self.flow_desc = get_flow_desc(self.repo, self.course, flow_identifier, self.commit_sha) # {{{ figure out permissions # Fetch current version of the flow to compute permissions, # fall back to 'old' version if current git version does not # contain this flow any more. from django.core.exceptions import ObjectDoesNotExist try: permissions_flow_desc = get_flow_desc(self.repo, self.course, flow_identifier, self.course_commit_sha) except ObjectDoesNotExist: permissions_flow_desc = self.flow_desc from course.views import get_now_or_fake_time self.permissions, self.stipulations = get_flow_permissions( self.course, self.participation, self.role, flow_identifier, permissions_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 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.commit_sha) RESUME_RE = re.compile("^resume_([0-9]+)$") @transaction.atomic def start_flow(request, course_identifier, flow_identifier): fctx = FlowContext(request, course_identifier, flow_identifier) from course.models import flow_permission if flow_permission.view not in fctx.permissions: raise PermissionDenied() have_in_progress_session = (FlowSession.objects .filter( participation=fctx.participation, flow_id=fctx.flow_identifier, in_progress=True, participation__isnull=False, )).count() > 0 past_sessions = (FlowSession.objects .filter( participation=fctx.participation, flow_id=fctx.flow_identifier, participation__isnull=False) .order_by("start_time")) past_session_count = past_sessions.count() if hasattr(fctx.stipulations, "allowed_session_count"): allowed_another_session = ( past_session_count < fctx.stipulations.allowed_session_count) else: allowed_another_session = True if request.method == "POST": from course.content import set_up_flow_session_page_data resume_match = None for post_key in request.POST: resume_match = RESUME_RE.match(post_key) if resume_match is not None: break if resume_match is not None: resume_session_id = int(resume_match.group(1)) resume_session = get_object_or_404(FlowSession, pk=resume_session_id) if resume_session.participation != fctx.participation: raise PermissionDenied("not your session") if resume_session.participation is None: raise PermissionDenied("can't resume anonymous session") if resume_session.flow_id != fctx.flow_identifier: raise SuspiciousOperation("flow id mismatch on resume") if not (flow_permission.view_past in fctx.permissions or resume_session.in_progress): raise PermissionDenied("not allowed to resume session") request.session["flow_session_id"] = resume_session_id return redirect("course.flow.view_flow_page", course_identifier, flow_identifier, 0) elif ("start_no_credit" in request.POST or "start_credit" in request.POST): if not allowed_another_session: raise PermissionDenied("new session would exceed " "allowed session count limit exceed") if have_in_progress_session: raise PermissionDenied("cannot start flow when other flow " "is already in progress") session = FlowSession() session.course = fctx.course session.participation = fctx.participation session.active_git_commit_sha = fctx.commit_sha.decode() session.flow_id = flow_identifier session.in_progress = True session.for_credit = "start_credit" in request.POST session.save() request.session["flow_session_id"] = session.id page_count = set_up_flow_session_page_data(fctx.repo, session, course_identifier, fctx.flow_desc, fctx.commit_sha) session.page_count = page_count session.save() return redirect("course.flow.view_flow_page", course_identifier, flow_identifier, 0) else: raise SuspiciousOperation("unrecognized POST action") else: may_start_credit = ( not have_in_progress_session and allowed_another_session and flow_permission.start_credit in fctx.permissions) may_start_no_credit = ( not have_in_progress_session and allowed_another_session and flow_permission.start_no_credit in fctx.permissions) may_review = ( flow_permission.view_past in fctx.permissions) if hasattr(fctx.flow_desc, "grade_aggregation_strategy"): from course.models import GRADE_AGGREGATION_STRATEGY_CHOICES grade_aggregation_strategy_text = ( dict(GRADE_AGGREGATION_STRATEGY_CHOICES) [fctx.flow_desc.grade_aggregation_strategy]) else: grade_aggregation_strategy_text = None return render(request, "course/flow-start.html", { "participation": fctx.participation, "course_desc": fctx.course_desc, "course": fctx.course, "flow_desc": fctx.flow_desc, "role": fctx.role, "participation_role": participation_role, "grade_aggregation_strategy": grade_aggregation_strategy_text, "flow_identifier": flow_identifier, "may_start_credit": may_start_credit, "may_start_no_credit": may_start_no_credit, "may_review": may_review, "past_sessions": past_sessions, "stipulations": fctx.stipulations, }) # }}} # {{{ flow page 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.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 = False 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 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 find_current_flow_session(request, flow_identifier): flow_session = None flow_session_id = request.session.get("flow_session_id") if flow_session_id is not None: flow_sessions = list(FlowSession.objects.filter(id=flow_session_id)) if flow_sessions and flow_sessions[0].flow_id == flow_identifier: flow_session, = flow_sessions return flow_session def add_buttons_to_form(fpctx, form): from crispy_forms.layout import Submit form.helper.add_input( Submit("save", "Save answer", css_class="col-lg-offset-2")) if fpctx.will_receive_feedback(): if flow_permission.change_answer in fpctx.permissions: form.helper.add_input(Submit("submit", "Submit answer for grading")) else: form.helper.add_input(Submit("submit", "Submit final answer")) else: # Only offer 'save and move on' if student will receive no feedback if fpctx.page_data.ordinal + 1 < fpctx.flow_session.page_count: form.helper.add_input( Submit("save_and_next", mark_safe("Save answer and move on »"))) else: form.helper.add_input( Submit("save_and_finish", mark_safe("Save answer and finish »"))) return form def get_pressed_button(form): buttons = ["save", "save_and_next", "save_and_finish", "submit"] for button in buttons: if button in form.data: return button raise SuspiciousOperation("could not find which button was pressed") def view_flow_page(request, course_identifier, flow_identifier, ordinal): flow_session = find_current_flow_session(request, flow_identifier) if flow_session is None: messages.add_message(request, messages.WARNING, "No in-progress session record found for this flow. " "Redirected to flow start page.") return redirect("course.flow.start_flow", course_identifier, flow_identifier) fpctx = FlowPageContext(request, course_identifier, flow_identifier, ordinal, flow_session) page_context = fpctx.page_context page_data = fpctx.page_data if flow_permission.view not in fpctx.permissions: raise PermissionDenied("not allowed to view flow") if request.method == "POST": if "finish" in request.POST: return redirect("course.flow.finish_flow", course_identifier, flow_identifier) else: # reject answer update if flow is not in-progress if not flow_session.in_progress: raise PermissionDenied("session is not in progress") # reject if previous answer was final if (fpctx.prev_answer_was_graded and flow_permission.change_answer not in fpctx.permissions): raise PermissionDenied("already have final answer") form, form_html = fpctx.page.post_form( fpctx.page_context, fpctx.page_data.data, post_data=request.POST, files_data=request.POST) pressed_button = get_pressed_button(form) if form.is_valid(): # {{{ form validated, process answer messages.add_message(request, messages.INFO, "Answer saved.") page_visit = FlowPageVisit() page_visit.flow_session = fpctx.flow_session page_visit.page_data = fpctx.page_data page_visit.remote_address = request.META['REMOTE_ADDR'] page_visit.answer = fpctx.page.answer_data( fpctx.page_context, fpctx.page_data.data, form) page_visit.is_graded_answer = pressed_button == "submit" page_visit.save() answer_data = page_visit.answer answer_was_graded = page_visit.is_graded_answer may_change_answer = ( not answer_was_graded or flow_permission.change_answer in fpctx.permissions) if (pressed_button == "save_and_next" and not fpctx.will_receive_feedback()): return redirect("course.flow.view_flow_page", course_identifier, flow_identifier, fpctx.ordinal + 1) elif (pressed_button == "save_and_finish" and not fpctx.will_receive_feedback()): return redirect("course.flow.finish_flow", course_identifier, flow_identifier) else: # continue at common flow page generation below form, form_html = fpctx.page.make_form( page_context, page_data.data, page_visit.answer, not may_change_answer) # continue at common flow page generation below # }}} else: # form did not validate fpctx.create_visit(request) answer_data = None answer_was_graded = False may_change_answer = True # because we were allowed this far in by the check above # continue at common flow page generation below else: fpctx.create_visit(request) answer_data = fpctx.prev_answer answer_was_graded = fpctx.prev_answer_was_graded may_change_answer = ( (not answer_was_graded or flow_permission.change_answer in fpctx.permissions) # can happen if no answer was ever saved and fpctx.flow_session.in_progress) if fpctx.page.expects_answer(): form, form_html = fpctx.page.make_form( page_context, page_data.data, answer_data, not may_change_answer) else: form = None form_html = None # start common flow page generation # defined at this point: # form, form_template, answer_data, may_change_answer, answer_was_graded if form is not None and may_change_answer: form = add_buttons_to_form(fpctx, form) show_correctness = None show_answer = None feedback = None if fpctx.page.expects_answer() and answer_was_graded: show_correctness = flow_permission.see_correctness in fpctx.permissions show_answer = flow_permission.see_answer in fpctx.permissions if show_correctness or show_answer: feedback = fpctx.page.grade( page_context, page_data.data, answer_data, # FIXME grade_data=None) title = fpctx.page.title(page_context, page_data.data) body = fpctx.page.body(page_context, page_data.data) # {{{ render flow page if form is not None and form_html is None: from crispy_forms.utils import render_crispy_form from django.template import RequestContext context = RequestContext(request, {}) form_html = render_crispy_form(form, context=context) del context form_html = '
%s
' % form_html args = { "course": fpctx.course, "course_desc": fpctx.course_desc, "flow_identifier": fpctx.flow_identifier, "flow_desc": fpctx.flow_desc, "ordinal": fpctx.ordinal, "page_data": fpctx.page_data, "percentage": fpctx.percentage_done, "flow_session": fpctx.flow_session, "participation": fpctx.participation, "role": fpctx.role, "participation_role": participation_role, "title": title, "body": body, "form_html": form_html, "feedback": feedback, "show_correctness": show_correctness, "show_answer": show_answer, } if fpctx.page.expects_answer(): args["max_points"] = fpctx.page.max_points(fpctx.page_data) return render(request, "course/flow-page.html", args) # }}} # }}} # {{{ finish flow def assemble_answer_visits(flow_session): answer_visits = [None] * flow_session.page_count from course.models import FlowPageVisit answer_page_visits = (FlowPageVisit.objects .filter(flow_session=flow_session) .filter(answer__isnull=False) .order_by("visit_time")) for page_visit in answer_page_visits: answer_visits[page_visit.page_data.ordinal] = page_visit return answer_visits def count_answered(fctx, answer_visits): all_page_data = (FlowPageData.objects .filter(flow_session=fctx.flow_session) .order_by("ordinal")) answered_count = 0 unanswered_count = 0 for i, page_data in enumerate(all_page_data): assert i == page_data.ordinal if answer_visits[i] is not None: answer_data = answer_visits[i].answer else: answer_data = None page = instantiate_flow_page_with_ctx(fctx, page_data) if page.expects_answer(): if answer_data is None: unanswered_count += 1 else: answered_count += 1 return (answered_count, unanswered_count) class GradeInfo(object): def __init__(self, points, max_points, fully_correct_count, partially_correct_count, incorrect_count): self.points = points self.max_points = max_points self.fully_correct_count = fully_correct_count self.partially_correct_count = partially_correct_count self.incorrect_count = incorrect_count def points_percent(self): return 100*self.points/self.max_points def missed_points_percent(self): return 100 - self.points_percent() def total_count(self): return (self.fully_correct_count + self.partially_correct_count + self.incorrect_count) def fully_correct_percent(self): return 100*self.fully_correct_count/self.total_count() def partially_correct_percent(self): return 100*self.partially_correct_count/self.total_count() def incorrect_percent(self): return 100*self.incorrect_count/self.total_count() def gather_grade_info(fctx, answer_visits): all_page_data = (FlowPageData.objects .filter(flow_session=fctx.flow_session) .order_by("ordinal")) points = 0 max_points = 0 fully_correct_count = 0 partially_correct_count = 0 incorrect_count = 0 for i, page_data in enumerate(all_page_data): assert i == page_data.ordinal if answer_visits[i] is not None: answer_data = answer_visits[i].answer grade_data = answer_visits[i].grade_data else: answer_data = None grade_data = None page = instantiate_flow_page_with_ctx(fctx, page_data) if not page.expects_answer(): continue from course.page import PageContext page_context = PageContext( course=fctx.course, repo=fctx.repo, commit_sha=fctx.commit_sha) feedback = page.grade( page_context, page_data.data, answer_data, grade_data) max_points += page.max_points(page_data.data) points += page.max_points(page_data.data)*feedback.correctness if feedback.correctness == 1: fully_correct_count += 1 elif feedback.correctness == 0: incorrect_count += 1 else: partially_correct_count += 1 return GradeInfo( points=points, max_points=max_points, fully_correct_count=fully_correct_count, partially_correct_count=partially_correct_count, incorrect_count=incorrect_count) @transaction.atomic def finish_flow(request, course_identifier, flow_identifier): flow_session = find_current_flow_session(request, flow_identifier) if flow_session is None: messages.add_message(request, messages.WARNING, "No session record found for this flow. " "Redirected to flow start page.") return redirect("course.flow.start_flow", course_identifier, flow_identifier) fctx = FlowContext(request, course_identifier, flow_identifier, flow_session=flow_session) answer_visits = assemble_answer_visits(flow_session) from course.content import markup_to_html completion_text = markup_to_html( fctx.course, fctx.repo, fctx.commit_sha, fctx.flow_desc.completion_text) (answered_count, unanswered_count) = count_answered(fctx, answer_visits) print answered_count, unanswered_count def render_finish_response(template, **kwargs): render_args = { "course": fctx.course, "course_desc": fctx.course_desc, "flow_identifier": fctx.flow_identifier, "flow_desc": fctx.flow_desc, "participation": fctx.participation, "role": fctx.role, "participation_role": participation_role, } render_args.update(kwargs) return render(request, template, render_args) if request.method == "POST": if "submit" not in request.POST: raise SuspiciousOperation("odd POST parameters") if not flow_session.in_progress: raise PermissionDenied("Can't end a session that's already ended") # Actually end the flow. request.session["flow_session_id"] = None grade_info = gather_grade_info(fctx, answer_visits) points = grade_info.points comment = None if hasattr(fctx.stipulations, "credit_percent"): comment = "Counted at %.1f%% of %.1f points" % ( fctx.stipulations.credit_percent, points) points = points * fctx.stipulations.credit_percent / 100 from django.utils.timezone import now flow_session.completion_time = now() flow_session.in_progress = False flow_session.points = points flow_session.max_points = grade_info.max_points flow_session.result_comment = comment flow_session.save() if answered_count + unanswered_count: # {{{ there is a grade to be had--assign it # {{{ mark answers as final for answer_visit in answer_visits: if answer_visit is not None: answer_visit.is_graded_answer = True answer_visit.save() # }}} from course.models import get_flow_grading_opportunity gopp = get_flow_grading_opportunity( fctx.course, fctx.flow_identifier, fctx.flow_desc) from course.models import grade_state_change_types gchange = GradeChange() gchange.opportunity = gopp gchange.participation = fctx.participation gchange.state = grade_state_change_types.graded gchange.points = points gchange.max_points = grade_info.max_points gchange.creator = request.user gchange.flow_session = flow_session gchange.comment = comment gchange.save() return render_finish_response( "course/flow-completion-grade.html", completion_text=completion_text, grade_info=grade_info) # }}} else: # {{{ no grade return render_finish_response( "course/flow-completion.html", last_page_nr=None, completion_text=completion_text) # }}} if (answered_count + unanswered_count == 0 and fctx.commit_sha == fctx.course_commit_sha): # Not serious--no questions in flow, and no new version available. # No need to end the flow visit. return render_finish_response( "course/flow-completion.html", last_page_nr=fctx.page_count-1, completion_text=completion_text) elif not flow_session.in_progress: # Just reviewing: re-show grades. grade_info = gather_grade_info(fctx, answer_visits) return render_finish_response( "course/flow-completion-grade.html", completion_text=completion_text, grade_info=grade_info) else: # confirm ending flow return render_finish_response( "course/flow-confirm-completion.html", last_page_nr=fctx.page_count-1, answered_count=answered_count, unanswered_count=unanswered_count, total_count=answered_count+unanswered_count) # }}} # vim: foldmethod=marker