"""
Views for hint management.
Get to these views through courseurl/hint_manager.
For example: https://courses.edx.org/courses/MITx/2.01x/2013_Spring/hint_manager
These views will only be visible if FEATURES['ENABLE_HINTER_INSTRUCTOR_VIEW'] = True
"""
import json
import re
from django.http import HttpResponse, Http404
from django.views.decorators.csrf import ensure_csrf_cookie
from edxmako.shortcuts import render_to_response, render_to_string
from courseware.courses import get_course_with_access
from courseware.models import XModuleUserStateSummaryField
import courseware.module_render as module_render
import courseware.model_data as model_data
from xmodule.modulestore.django import modulestore
from opaque_keys.edx.locations import SlashSeparatedCourseKey
from xmodule.modulestore.exceptions import ItemNotFoundError
@ensure_csrf_cookie
def hint_manager(request, course_id):
"""
The URL landing function for all calls to the hint manager, both POST and GET.
"""
course_key = SlashSeparatedCourseKey.from_deprecated_string(course_id)
try:
course = get_course_with_access(request.user, 'staff', course_key, depth=None)
except Http404:
out = 'Sorry, but students are not allowed to access the hint manager!'
return HttpResponse(out)
if request.method == 'GET':
out = get_hints(request, course_key, 'mod_queue')
out.update({'error': ''})
return render_to_response('instructor/hint_manager.html', out)
field = request.POST['field']
if not (field == 'mod_queue' or field == 'hints'):
# Invalid field. (Don't let users continue - they may overwrite other db's)
out = 'Error in hint manager - an invalid field was accessed.'
return HttpResponse(out)
switch_dict = {
'delete hints': delete_hints,
'switch fields': lambda *args: None, # Takes any number of arguments, returns None.
'change votes': change_votes,
'add hint': add_hint,
'approve': approve,
}
# Do the operation requested, and collect any error messages.
error_text = switch_dict[request.POST['op']](request, course_key, field)
if error_text is None:
error_text = ''
render_dict = get_hints(request, course_key, field, course=course)
render_dict.update({'error': error_text})
rendered_html = render_to_string('instructor/hint_manager_inner.html', render_dict)
return HttpResponse(json.dumps({'success': True, 'contents': rendered_html}))
def get_hints(request, course_id, field, course=None): # pylint: disable=unused-argument
"""
Load all of the hints submitted to the course.
Args:
`request` -- Django request object.
`course_id` -- The course id, like 'Me/19.002/test_course'
`field` -- Either 'hints' or 'mod_queue'; specifies which set of hints to load.
Keys in returned dict:
- 'field': Same as input
- 'other_field': 'mod_queue' if `field` == 'hints'; and vice-versa.
- 'field_label', 'other_field_label': English name for the above.
- 'all_hints': A list of [answer, pk dict] pairs, representing all hints.
Sorted by answer.
- 'id_to_name': A dictionary mapping problem id to problem name.
"""
if field == 'mod_queue':
other_field = 'hints'
field_label = 'Hints Awaiting Moderation'
other_field_label = 'Approved Hints'
elif field == 'hints':
other_field = 'mod_queue'
field_label = 'Approved Hints'
other_field_label = 'Hints Awaiting Moderation'
# We want to use the course_id to find all matching usage_id's.
# To do this, just take the school/number part - leave off the classname.
# FIXME: we need to figure out how to do this with opaque keys
all_hints = XModuleUserStateSummaryField.objects.filter(
field_name=field,
usage_id__regex=re.escape(u'{0.org}/{0.course}'.format(course_id)),
)
# big_out_dict[problem id] = [[answer, {pk: [hint, votes]}], sorted by answer]
# big_out_dict maps a problem id to a list of [answer, hints] pairs, sorted in order of answer.
big_out_dict = {}
# id_to name maps a problem id to the name of the problem.
# id_to_name[problem id] = Display name of problem
id_to_name = {}
for hints_by_problem in all_hints:
hints_by_problem.usage_id = hints_by_problem.usage_id.map_into_course(course_id)
name = location_to_problem_name(course_id, hints_by_problem.usage_id)
if name is None:
continue
id_to_name[hints_by_problem.usage_id] = name
def answer_sorter(thing):
"""
`thing` is a tuple, where `thing[0]` contains an answer, and `thing[1]` contains
a dict of hints. This function returns an index based on `thing[0]`, which
is used as a key to sort the list of things.
"""
try:
return float(thing[0])
except ValueError:
# Put all non-numerical answers first.
return float('-inf')
# Answer list contains [answer, dict_of_hints] pairs.
answer_list = sorted(json.loads(hints_by_problem.value).items(), key=answer_sorter)
big_out_dict[hints_by_problem.usage_id] = answer_list
render_dict = {'field': field,
'other_field': other_field,
'field_label': field_label,
'other_field_label': other_field_label,
'all_hints': big_out_dict,
'id_to_name': id_to_name}
return render_dict
def location_to_problem_name(course_id, loc):
"""
Given the location of a crowdsource_hinter module, try to return the name of the
problem it wraps around. Return None if the hinter no longer exists.
"""
try:
descriptor = modulestore().get_item(loc)
return descriptor.get_children()[0].display_name
except ItemNotFoundError:
# Sometimes, the problem is no longer in the course. Just
# don't include said problem.
return None
def delete_hints(request, course_id, field, course=None): # pylint: disable=unused-argument
"""
Deletes the hints specified.
`request.POST` contains some fields keyed by integers. Each such field contains a
[problem_defn_id, answer, pk] tuple. These tuples specify the hints to be deleted.
Example `request.POST`:
{'op': 'delete_hints',
'field': 'mod_queue',
1: ['problem_whatever', '42.0', '3'],
2: ['problem_whatever', '32.5', '12']}
"""
for key in request.POST:
if key == 'op' or key == 'field':
continue
problem_id, answer, pk = request.POST.getlist(key)
problem_key = course_id.make_usage_key_from_deprecated_string(problem_id)
# Can be optimized - sort the delete list by problem_id, and load each problem
# from the database only once.
this_problem = XModuleUserStateSummaryField.objects.get(field_name=field, usage_id=problem_key)
problem_dict = json.loads(this_problem.value)
del problem_dict[answer][pk]
this_problem.value = json.dumps(problem_dict)
this_problem.save()
def change_votes(request, course_id, field, course=None): # pylint: disable=unused-argument
"""
Updates the number of votes.
The numbered fields of `request.POST` contain [problem_id, answer, pk, new_votes] tuples.
See `delete_hints`.
Example `request.POST`:
{'op': 'delete_hints',
'field': 'mod_queue',
1: ['problem_whatever', '42.0', '3', 42],
2: ['problem_whatever', '32.5', '12', 9001]}
"""
for key in request.POST:
if key == 'op' or key == 'field':
continue
problem_id, answer, pk, new_votes = request.POST.getlist(key)
problem_key = course_id.make_usage_key_from_deprecated_string(problem_id)
this_problem = XModuleUserStateSummaryField.objects.get(field_name=field, usage_id=problem_key)
problem_dict = json.loads(this_problem.value)
# problem_dict[answer][pk] points to a [hint_text, #votes] pair.
problem_dict[answer][pk][1] = int(new_votes)
this_problem.value = json.dumps(problem_dict)
this_problem.save()
def add_hint(request, course_id, field, course=None):
"""
Add a new hint. `request.POST`:
op
field
problem - The problem id
answer - The answer to which a hint will be added
hint - The text of the hint
"""
problem_id = request.POST['problem']
problem_key = course_id.make_usage_key_from_deprecated_string(problem_id)
answer = request.POST['answer']
hint_text = request.POST['hint']
# Validate the answer. This requires initializing the xmodules, which
# is annoying.
try:
descriptor = modulestore().get_item(problem_key)
descriptors = [descriptor]
except ItemNotFoundError:
descriptors = []
field_data_cache = model_data.FieldDataCache(descriptors, course_id, request.user)
hinter_module = module_render.get_module(
request.user,
request,
problem_key,
field_data_cache,
course_id,
course=course
)
if not hinter_module.validate_answer(answer):
# Invalid answer. Don't add it to the database, or else the
# hinter will crash when we encounter it.
return 'Error - the answer you specified is not properly formatted: ' + str(answer)
this_problem = XModuleUserStateSummaryField.objects.get(field_name=field, usage_id=problem_key)
hint_pk_entry = XModuleUserStateSummaryField.objects.get(field_name='hint_pk', usage_id=problem_key)
this_pk = int(hint_pk_entry.value)
hint_pk_entry.value = this_pk + 1
hint_pk_entry.save()
problem_dict = json.loads(this_problem.value)
if answer not in problem_dict:
problem_dict[answer] = {}
problem_dict[answer][this_pk] = [hint_text, 1]
this_problem.value = json.dumps(problem_dict)
this_problem.save()
def approve(request, course_id, field, course=None): # pylint: disable=unused-argument
"""
Approve a list of hints, moving them from the mod_queue to the real
hint list. POST:
op, field
(some number) -> [problem, answer, pk]
The numbered fields are analogous to those in `delete_hints` and `change_votes`.
"""
for key in request.POST:
if key == 'op' or key == 'field':
continue
problem_id, answer, pk = request.POST.getlist(key)
problem_key = course_id.make_usage_key_from_deprecated_string(problem_id)
# Can be optimized - sort the delete list by problem_id, and load each problem
# from the database only once.
problem_in_mod = XModuleUserStateSummaryField.objects.get(field_name=field, usage_id=problem_key)
problem_dict = json.loads(problem_in_mod.value)
hint_to_move = problem_dict[answer][pk]
del problem_dict[answer][pk]
problem_in_mod.value = json.dumps(problem_dict)
problem_in_mod.save()
problem_in_hints = XModuleUserStateSummaryField.objects.get(field_name='hints', usage_id=problem_key)
problem_dict = json.loads(problem_in_hints.value)
if answer not in problem_dict:
problem_dict[answer] = {}
problem_dict[answer][pk] = hint_to_move
problem_in_hints.value = json.dumps(problem_dict)
problem_in_hints.save()