class GradedAssignment(models.Model):
"""
Model representing a single launch of a graded assignment by an individual
user. There will be a row created here only if the LTI consumer may require
a result to be returned from the LTI launch (determined by the presence of
the lis_result_sourcedid parameter in the launch POST). There will be only
one row created for a given usage/consumer combination; repeated launches of
the same content by the same user from the same LTI consumer will not add
new rows to the table.
Some LTI-specified fields use the prefix lis_; this refers to the IMS
Learning Information Services standard from which LTI inherits some
properties
"""
user = models.ForeignKey(User, db_index=True)
course_key = CourseKeyField(max_length=255, db_index=True)
usage_key = UsageKeyField(max_length=255, db_index=True)
outcome_service = models.ForeignKey(OutcomeService)
lis_result_sourcedid = models.CharField(max_length=255, db_index=True)
version_number = models.IntegerField(default=0)
class Meta(object):
"""
Uniqueness constraints.
"""
unique_together = ('outcome_service', 'lis_result_sourcedid')
class PersistentSubsectionGrade(TimeStampedModel):
"""
A django model tracking persistent grades at the subsection level.
"""
class Meta(object):
unique_together = [
# * Specific grades can be pulled using all three columns,
# * Progress page can pull all grades for a given (course_id, user_id)
# * Course staff can see all grades for a course using (course_id,)
('course_id', 'user_id', 'usage_key'),
]
# primary key will need to be large for this table
id = UnsignedBigIntAutoField(primary_key=True) # pylint: disable=invalid-name
# uniquely identify this particular grade object
user_id = models.IntegerField(blank=False)
course_id = CourseKeyField(blank=False, max_length=255)
usage_key = UsageKeyField(blank=False, max_length=255)
# Information relating to the state of content when grade was calculated
subtree_edited_timestamp = models.DateTimeField(
'last content edit timestamp', blank=False)
course_version = models.CharField('guid of latest course version',
blank=True,
max_length=255)
# earned/possible refers to the number of points achieved and available to achieve.
# graded refers to the subset of all problems that are marked as being graded.
earned_all = models.FloatField(blank=False)
possible_all = models.FloatField(blank=False)
earned_graded = models.FloatField(blank=False)
possible_graded = models.FloatField(blank=False)
# track which blocks were visible at the time of grade calculation
visible_blocks = models.ForeignKey(VisibleBlocks,
db_column='visible_blocks_hash',
to_field='hashed')
# use custom manager
objects = PersistentSubsectionGradeQuerySet.as_manager()
def __unicode__(self):
"""
Returns a string representation of this model.
"""
return u"{} user: {}, course version: {}, subsection {} ({}). {}/{} graded, {}/{} all".format(
type(self).__name__,
self.user_id,
self.course_version,
self.usage_key,
self.visible_blocks_id,
self.earned_graded,
self.possible_graded,
self.earned_all,
self.possible_all,
)
@classmethod
def save_grade(cls, **kwargs):
"""
Wrapper for create_grade or update_grade, depending on which applies.
Takes the same arguments as both of those methods.
"""
user_id = kwargs.pop('user_id')
usage_key = kwargs.pop('usage_key')
try:
with transaction.atomic():
grade, is_created = cls.objects.get_or_create(
user_id=user_id,
course_id=usage_key.course_key,
usage_key=usage_key,
defaults=kwargs,
)
log.info(
u"Persistent Grades: Grade model saved: {0}".format(grade))
except IntegrityError:
cls.update_grade(user_id=user_id, usage_key=usage_key, **kwargs)
log.warning(
u"Persistent Grades: Integrity error trying to save grade for user: {0}, usage key: {1}, defaults: {2}"
.format(user_id, usage_key, **kwargs))
else:
if not is_created:
grade.update(**kwargs)
@classmethod
def read_grade(cls, user_id, usage_key):
"""
Reads a grade from database
Arguments:
user_id: The user associated with the desired grade
usage_key: The location of the subsection associated with the desired grade
Raises PersistentSubsectionGrade.DoesNotExist if applicable
"""
return cls.objects.get(
user_id=user_id,
course_id=usage_key.
course_key, # course_id is included to take advantage of db indexes
usage_key=usage_key,
)
@classmethod
def update_grade(
cls,
user_id,
usage_key,
course_version,
subtree_edited_timestamp,
earned_all,
possible_all,
earned_graded,
possible_graded,
visible_blocks,
):
"""
Updates a previously existing grade.
This is distinct from update() in that `grade.update()` operates on an
existing grade object, while this is a classmethod that pulls the grade
from the database, and then updates it. If you already have a grade
object, use the update() method on that object to avoid an extra
round-trip to the database. Use this classmethod if all you have are a
user and the usage key of an existing grade.
Requires all the arguments listed in docstring for create_grade
"""
grade = cls.read_grade(
user_id=user_id,
usage_key=usage_key,
)
grade.update(
course_version=course_version,
subtree_edited_timestamp=subtree_edited_timestamp,
earned_all=earned_all,
possible_all=possible_all,
earned_graded=earned_graded,
possible_graded=possible_graded,
visible_blocks=visible_blocks,
)
def update(
self,
course_version,
subtree_edited_timestamp,
earned_all,
possible_all,
earned_graded,
possible_graded,
visible_blocks,
):
"""
Modify an existing PersistentSubsectionGrade object, saving the new
version.
"""
visible_blocks_hash = VisibleBlocks.objects.hash_from_blockrecords(
BlockRecordList.from_list(visible_blocks))
self.course_version = course_version or ""
self.subtree_edited_timestamp = subtree_edited_timestamp
self.earned_all = earned_all
self.possible_all = possible_all
self.earned_graded = earned_graded
self.possible_graded = possible_graded
self.visible_blocks_id = visible_blocks_hash # pylint: disable=attribute-defined-outside-init
self.save()
log.info(u"Persistent Grades: Grade model updated: {0}".format(self))
class CourseOverview(TimeStampedModel):
"""
Model for storing and caching basic information about a course.
This model contains basic course metadata such as an ID, display name,
image URL, and any other information that would be necessary to display
a course as part of a user dashboard or enrollment API.
"""
# IMPORTANT: Bump this whenever you modify this model and/or add a migration.
VERSION = 1
# Cache entry versioning.
version = IntegerField()
# Course identification
id = CourseKeyField(db_index=True, primary_key=True, max_length=255) # pylint: disable=invalid-name
_location = UsageKeyField(max_length=255)
display_name = TextField(null=True)
display_number_with_default = TextField()
display_org_with_default = TextField()
# Start/end dates
start = DateTimeField(null=True)
end = DateTimeField(null=True)
advertised_start = TextField(null=True)
# URLs
course_image_url = TextField()
facebook_url = TextField(null=True)
social_sharing_url = TextField(null=True)
end_of_course_survey_url = TextField(null=True)
# Certification data
certificates_display_behavior = TextField(null=True)
certificates_show_before_end = BooleanField()
cert_html_view_enabled = BooleanField()
has_any_active_web_certificate = BooleanField()
cert_name_short = TextField()
cert_name_long = TextField()
# Grading
lowest_passing_grade = DecimalField(max_digits=5,
decimal_places=2,
null=True)
# Access parameters
days_early_for_beta = FloatField(null=True)
mobile_available = BooleanField()
visible_to_staff_only = BooleanField()
_pre_requisite_courses_json = TextField(
) # JSON representation of list of CourseKey strings
# Enrollment details
enrollment_start = DateTimeField(null=True)
enrollment_end = DateTimeField(null=True)
enrollment_domain = TextField(null=True)
invitation_only = BooleanField(default=False)
max_student_enrollments_allowed = IntegerField(null=True)
@classmethod
def _create_from_course(cls, course):
"""
Creates a CourseOverview object from a CourseDescriptor.
Does not touch the database, simply constructs and returns an overview
from the given course.
Arguments:
course (CourseDescriptor): any course descriptor object
Returns:
CourseOverview: overview extracted from the given course
"""
from lms.djangoapps.certificates.api import get_active_web_certificate
from lms.djangoapps.courseware.courses import course_image_url
# Workaround for a problem discovered in https://openedx.atlassian.net/browse/TNL-2806.
# If the course has a malformed grading policy such that
# course._grading_policy['GRADE_CUTOFFS'] = {}, then
# course.lowest_passing_grade will raise a ValueError.
# Work around this for now by defaulting to None.
try:
lowest_passing_grade = course.lowest_passing_grade
except ValueError:
lowest_passing_grade = None
display_name = course.display_name
start = course.start
end = course.end
if isinstance(course.id, CCXLocator):
from ccx.utils import get_ccx_from_ccx_locator # pylint: disable=import-error
ccx = get_ccx_from_ccx_locator(course.id)
display_name = ccx.display_name
start = ccx.start
end = ccx.due
return cls(
version=cls.VERSION,
id=course.id,
_location=course.location,
display_name=display_name,
display_number_with_default=course.display_number_with_default,
display_org_with_default=course.display_org_with_default,
start=start,
end=end,
advertised_start=course.advertised_start,
course_image_url=course_image_url(course),
facebook_url=course.facebook_url,
social_sharing_url=course.social_sharing_url,
certificates_display_behavior=course.certificates_display_behavior,
certificates_show_before_end=course.certificates_show_before_end,
cert_html_view_enabled=course.cert_html_view_enabled,
has_any_active_web_certificate=(get_active_web_certificate(course)
is not None),
cert_name_short=course.cert_name_short,
cert_name_long=course.cert_name_long,
lowest_passing_grade=lowest_passing_grade,
end_of_course_survey_url=course.end_of_course_survey_url,
days_early_for_beta=course.days_early_for_beta,
mobile_available=course.mobile_available,
visible_to_staff_only=course.visible_to_staff_only,
_pre_requisite_courses_json=json.dumps(
course.pre_requisite_courses),
enrollment_start=course.enrollment_start,
enrollment_end=course.enrollment_end,
enrollment_domain=course.enrollment_domain,
invitation_only=course.invitation_only,
max_student_enrollments_allowed=course.
max_student_enrollments_allowed,
)
@classmethod
def load_from_module_store(cls, course_id):
"""
Load a CourseDescriptor, create a new CourseOverview from it, cache the
overview, and return it.
Arguments:
course_id (CourseKey): the ID of the course overview to be loaded.
Returns:
CourseOverview: overview of the requested course.
Raises:
- CourseOverview.DoesNotExist if the course specified by course_id
was not found.
- IOError if some other error occurs while trying to load the
course from the module store.
"""
store = modulestore()
with store.bulk_operations(course_id):
course = store.get_course(course_id)
if isinstance(course, CourseDescriptor):
course_overview = cls._create_from_course(course)
try:
course_overview.save()
except IntegrityError:
# There is a rare race condition that will occur if
# CourseOverview.get_from_id is called while a
# another identical overview is already in the process
# of being created.
# One of the overviews will be saved normally, while the
# other one will cause an IntegrityError because it tries
# to save a duplicate.
# (see: https://openedx.atlassian.net/browse/TNL-2854).
pass
return course_overview
elif course is not None:
raise IOError(
"Error while loading course {} from the module store: {}",
unicode(course_id), course.error_msg if isinstance(
course, ErrorDescriptor) else unicode(course))
else:
raise cls.DoesNotExist()
@classmethod
def get_from_id(cls, course_id):
"""
Load a CourseOverview object for a given course ID.
First, we try to load the CourseOverview from the database. If it
doesn't exist, we load the entire course from the modulestore, create a
CourseOverview object from it, and then cache it in the database for
future use.
Arguments:
course_id (CourseKey): the ID of the course overview to be loaded.
Returns:
CourseOverview: overview of the requested course.
Raises:
- CourseOverview.DoesNotExist if the course specified by course_id
was not found.
- IOError if some other error occurs while trying to load the
course from the module store.
"""
try:
course_overview = cls.objects.get(id=course_id)
if course_overview.version != cls.VERSION:
# Throw away old versions of CourseOverview, as they might contain stale data.
course_overview.delete()
course_overview = None
except cls.DoesNotExist:
course_overview = None
return course_overview or cls.load_from_module_store(course_id)
def clean_id(self, padding_char='='):
"""
Returns a unique deterministic base32-encoded ID for the course.
Arguments:
padding_char (str): Character used for padding at end of base-32
-encoded string, defaulting to '='
"""
return course_metadata_utils.clean_course_key(self.location.course_key,
padding_char)
@property
def location(self):
"""
Returns the UsageKey of this course.
UsageKeyField has a strange behavior where it fails to parse the "run"
of a course out of the serialized form of a Mongo Draft UsageKey. This
method is a wrapper around _location attribute that fixes the problem
by calling map_into_course, which restores the run attribute.
"""
if self._location.run is None:
self._location = self._location.map_into_course(self.id)
return self._location
@property
def number(self):
"""
Returns this course's number.
This is a "number" in the sense of the "course numbers" that you see at
lots of universities. For example, given a course
"Intro to Computer Science" with the course key "edX/CS-101/2014", the
course number would be "CS-101"
"""
return course_metadata_utils.number_for_course_location(self.location)
@property
def url_name(self):
"""
Returns this course's URL name.
"""
return course_metadata_utils.url_name_for_course_location(
self.location)
@property
def display_name_with_default(self):
"""
Return reasonable display name for the course.
"""
return course_metadata_utils.display_name_with_default(self)
def has_started(self):
"""
Returns whether the the course has started.
"""
return course_metadata_utils.has_course_started(self.start)
def has_ended(self):
"""
Returns whether the course has ended.
"""
return course_metadata_utils.has_course_ended(self.end)
def starts_within(self, days):
"""
Returns True if the course starts with-in given number of days otherwise returns False.
"""
return course_metadata_utils.course_starts_within(self.start, days)
def start_datetime_text(self, format_string="SHORT_DATE"):
"""
Returns the desired text corresponding the course's start date and
time in UTC. Prefers .advertised_start, then falls back to .start.
"""
return course_metadata_utils.course_start_datetime_text(
self.start, self.advertised_start, format_string, ugettext,
strftime_localized)
@property
def start_date_is_still_default(self):
"""
Checks if the start date set for the course is still default, i.e.
.start has not been modified, and .advertised_start has not been set.
"""
return course_metadata_utils.course_start_date_is_default(
self.start,
self.advertised_start,
)
def end_datetime_text(self, format_string="SHORT_DATE"):
"""
Returns the end date or datetime for the course formatted as a string.
"""
return course_metadata_utils.course_end_datetime_text(
self.end, format_string, strftime_localized)
def may_certify(self):
"""
Returns whether it is acceptable to show the student a certificate
download link.
"""
return course_metadata_utils.may_certify_for_course(
self.certificates_display_behavior,
self.certificates_show_before_end, self.has_ended())
@property
def pre_requisite_courses(self):
"""
Returns a list of ID strings for this course's prerequisite courses.
"""
return json.loads(self._pre_requisite_courses_json)
@classmethod
def get_all_course_keys(cls):
"""
Returns all course keys from course overviews.
"""
return [
CourseKey.from_string(course_overview['id'])
for course_overview in CourseOverview.objects.values('id')
]
class CourseOverview(TimeStampedModel):
"""
Model for storing and caching basic information about a course.
This model contains basic course metadata such as an ID, display name,
image URL, and any other information that would be necessary to display
a course as part of:
user dashboard (enrolled courses)
course catalog (courses to enroll in)
course about (meta data about the course)
"""
class Meta(object):
app_label = 'course_overviews'
# IMPORTANT: Bump this whenever you modify this model and/or add a migration.
VERSION = 4
# Cache entry versioning.
version = IntegerField()
# Course identification
id = CourseKeyField(db_index=True, primary_key=True, max_length=255)
_location = UsageKeyField(max_length=255)
org = TextField(max_length=255, default='outdated_entry')
display_name = TextField(null=True)
display_number_with_default = TextField()
display_org_with_default = TextField()
# Start/end dates
start = DateTimeField(null=True)
end = DateTimeField(null=True)
advertised_start = TextField(null=True)
announcement = DateTimeField(null=True)
# URLs
course_image_url = TextField()
social_sharing_url = TextField(null=True)
end_of_course_survey_url = TextField(null=True)
# Certification data
certificates_display_behavior = TextField(null=True)
certificates_show_before_end = BooleanField(default=False)
cert_html_view_enabled = BooleanField(default=False)
has_any_active_web_certificate = BooleanField(default=False)
cert_name_short = TextField()
cert_name_long = TextField()
# Grading
lowest_passing_grade = DecimalField(max_digits=5,
decimal_places=2,
null=True)
# Access parameters
days_early_for_beta = FloatField(null=True)
mobile_available = BooleanField(default=False)
visible_to_staff_only = BooleanField(default=False)
_pre_requisite_courses_json = TextField(
) # JSON representation of list of CourseKey strings
# Enrollment details
enrollment_start = DateTimeField(null=True)
enrollment_end = DateTimeField(null=True)
enrollment_domain = TextField(null=True)
invitation_only = BooleanField(default=False)
max_student_enrollments_allowed = IntegerField(null=True)
# Catalog information
catalog_visibility = TextField(null=True)
short_description = TextField(null=True)
course_video_url = TextField(null=True)
effort = TextField(null=True)
self_paced = BooleanField(default=False)
@classmethod
def _create_from_course(cls, course):
"""
Creates a CourseOverview object from a CourseDescriptor.
Does not touch the database, simply constructs and returns an overview
from the given course.
Arguments:
course (CourseDescriptor): any course descriptor object
Returns:
CourseOverview: overview extracted from the given course
"""
from lms.djangoapps.certificates.api import get_active_web_certificate
from openedx.core.lib.courses import course_image_url
log.info('Creating course overview for %s.', unicode(course.id))
# Workaround for a problem discovered in https://openedx.atlassian.net/browse/TNL-2806.
# If the course has a malformed grading policy such that
# course._grading_policy['GRADE_CUTOFFS'] = {}, then
# course.lowest_passing_grade will raise a ValueError.
# Work around this for now by defaulting to None.
try:
lowest_passing_grade = course.lowest_passing_grade
except ValueError:
lowest_passing_grade = None
display_name = course.display_name
start = course.start
end = course.end
max_student_enrollments_allowed = course.max_student_enrollments_allowed
if isinstance(course.id, CCXLocator):
from lms.djangoapps.ccx.utils import get_ccx_from_ccx_locator
ccx = get_ccx_from_ccx_locator(course.id)
display_name = ccx.display_name
start = ccx.start
end = ccx.due
max_student_enrollments_allowed = ccx.max_student_enrollments_allowed
return cls(
version=cls.VERSION,
id=course.id,
_location=course.location,
org=course.location.org,
display_name=display_name,
display_number_with_default=course.display_number_with_default,
display_org_with_default=course.display_org_with_default,
start=start,
end=end,
advertised_start=course.advertised_start,
announcement=course.announcement,
course_image_url=course_image_url(course),
social_sharing_url=course.social_sharing_url,
certificates_display_behavior=course.certificates_display_behavior,
certificates_show_before_end=course.certificates_show_before_end,
cert_html_view_enabled=course.cert_html_view_enabled,
has_any_active_web_certificate=(get_active_web_certificate(course)
is not None),
cert_name_short=course.cert_name_short,
cert_name_long=course.cert_name_long,
lowest_passing_grade=lowest_passing_grade,
end_of_course_survey_url=course.end_of_course_survey_url,
days_early_for_beta=course.days_early_for_beta,
mobile_available=course.mobile_available,
visible_to_staff_only=course.visible_to_staff_only,
_pre_requisite_courses_json=json.dumps(
course.pre_requisite_courses),
enrollment_start=course.enrollment_start,
enrollment_end=course.enrollment_end,
enrollment_domain=course.enrollment_domain,
invitation_only=course.invitation_only,
max_student_enrollments_allowed=max_student_enrollments_allowed,
catalog_visibility=course.catalog_visibility,
short_description=CourseDetails.fetch_about_attribute(
course.id, 'short_description'),
effort=CourseDetails.fetch_about_attribute(course.id, 'effort'),
course_video_url=CourseDetails.fetch_video_url(course.id),
self_paced=course.self_paced,
)
@classmethod
def load_from_module_store(cls, course_id):
"""
Load a CourseDescriptor, create a new CourseOverview from it, cache the
overview, and return it.
Arguments:
course_id (CourseKey): the ID of the course overview to be loaded.
Returns:
CourseOverview: overview of the requested course.
Raises:
- CourseOverview.DoesNotExist if the course specified by course_id
was not found.
- IOError if some other error occurs while trying to load the
course from the module store.
"""
store = modulestore()
with store.bulk_operations(course_id):
course = store.get_course(course_id)
if isinstance(course, CourseDescriptor):
course_overview = cls._create_from_course(course)
try:
with transaction.atomic():
course_overview.save()
CourseOverviewTab.objects.bulk_create([
CourseOverviewTab(tab_id=tab.tab_id,
course_overview=course_overview)
for tab in course.tabs
])
CourseOverviewImageSet.create_for_course(
course_overview, course)
except IntegrityError:
# There is a rare race condition that will occur if
# CourseOverview.get_from_id is called while a
# another identical overview is already in the process
# of being created.
# One of the overviews will be saved normally, while the
# other one will cause an IntegrityError because it tries
# to save a duplicate.
# (see: https://openedx.atlassian.net/browse/TNL-2854).
pass
return course_overview
elif course is not None:
raise IOError(
"Error while loading course {} from the module store: {}",
unicode(course_id), course.error_msg if isinstance(
course, ErrorDescriptor) else unicode(course))
else:
raise cls.DoesNotExist()
@classmethod
def get_from_id(cls, course_id):
"""
Load a CourseOverview object for a given course ID.
First, we try to load the CourseOverview from the database. If it
doesn't exist, we load the entire course from the modulestore, create a
CourseOverview object from it, and then cache it in the database for
future use.
Arguments:
course_id (CourseKey): the ID of the course overview to be loaded.
Returns:
CourseOverview: overview of the requested course.
Raises:
- CourseOverview.DoesNotExist if the course specified by course_id
was not found.
- IOError if some other error occurs while trying to load the
course from the module store.
"""
try:
course_overview = cls.objects.select_related('image_set').get(
id=course_id)
if course_overview.version < cls.VERSION:
# Throw away old versions of CourseOverview, as they might contain stale data.
course_overview.delete()
course_overview = None
except cls.DoesNotExist:
course_overview = None
# Regenerate the thumbnail images if they're missing (either because
# they were never generated, or because they were flushed out after
# a change to CourseOverviewImageConfig.
if course_overview and not hasattr(course_overview, 'image_set'):
CourseOverviewImageSet.create_for_course(course_overview)
return course_overview or cls.load_from_module_store(course_id)
def clean_id(self, padding_char='='):
"""
Returns a unique deterministic base32-encoded ID for the course.
Arguments:
padding_char (str): Character used for padding at end of base-32
-encoded string, defaulting to '='
"""
return course_metadata_utils.clean_course_key(self.location.course_key,
padding_char)
@property
def location(self):
"""
Returns the UsageKey of this course.
UsageKeyField has a strange behavior where it fails to parse the "run"
of a course out of the serialized form of a Mongo Draft UsageKey. This
method is a wrapper around _location attribute that fixes the problem
by calling map_into_course, which restores the run attribute.
"""
if self._location.run is None:
self._location = self._location.map_into_course(self.id)
return self._location
@property
def number(self):
"""
Returns this course's number.
This is a "number" in the sense of the "course numbers" that you see at
lots of universities. For example, given a course
"Intro to Computer Science" with the course key "edX/CS-101/2014", the
course number would be "CS-101"
"""
return course_metadata_utils.number_for_course_location(self.location)
@property
def url_name(self):
"""
Returns this course's URL name.
"""
return course_metadata_utils.url_name_for_course_location(
self.location)
@property
def display_name_with_default(self):
"""
Return reasonable display name for the course.
"""
return course_metadata_utils.display_name_with_default(self)
@property
def display_name_with_default_escaped(self):
"""
DEPRECATED: use display_name_with_default
Return html escaped reasonable display name for the course.
Note: This newly introduced method should not be used. It was only
introduced to enable a quick search/replace and the ability to slowly
migrate and test switching to display_name_with_default, which is no
longer escaped.
"""
return course_metadata_utils.display_name_with_default_escaped(self)
def has_started(self):
"""
Returns whether the the course has started.
"""
return course_metadata_utils.has_course_started(self.start)
def has_ended(self):
"""
Returns whether the course has ended.
"""
return course_metadata_utils.has_course_ended(self.end)
def starts_within(self, days):
"""
Returns True if the course starts with-in given number of days otherwise returns False.
"""
return course_metadata_utils.course_starts_within(self.start, days)
def start_datetime_text(self, format_string="SHORT_DATE"):
"""
Returns the desired text corresponding the course's start date and
time in UTC. Prefers .advertised_start, then falls back to .start.
"""
return course_metadata_utils.course_start_datetime_text(
self.start, self.advertised_start, format_string, ugettext,
strftime_localized)
@property
def start_date_is_still_default(self):
"""
Checks if the start date set for the course is still default, i.e.
.start has not been modified, and .advertised_start has not been set.
"""
return course_metadata_utils.course_start_date_is_default(
self.start,
self.advertised_start,
)
def end_datetime_text(self, format_string="SHORT_DATE"):
"""
Returns the end date or datetime for the course formatted as a string.
"""
return course_metadata_utils.course_end_datetime_text(
self.end, format_string, strftime_localized)
@property
def sorting_score(self):
"""
Returns a tuple that can be used to sort the courses according
the how "new" they are. The "newness" score is computed using a
heuristic that takes into account the announcement and
(advertised) start dates of the course if available.
The lower the number the "newer" the course.
"""
return course_metadata_utils.sorting_score(self.start,
self.advertised_start,
self.announcement)
@property
def start_type(self):
"""
Returns the type of the course's 'start' field.
"""
if self.advertised_start:
return u'string'
elif self.start != DEFAULT_START_DATE:
return u'timestamp'
else:
return u'empty'
@property
def start_display(self):
"""
Returns the display value for the course's start date.
"""
if self.advertised_start:
return self.advertised_start
elif self.start != DEFAULT_START_DATE:
return defaultfilters.date(self.start, "DATE_FORMAT")
else:
return None
def may_certify(self):
"""
Returns whether it is acceptable to show the student a certificate
download link.
"""
return course_metadata_utils.may_certify_for_course(
self.certificates_display_behavior,
self.certificates_show_before_end, self.has_ended())
@property
def pre_requisite_courses(self):
"""
Returns a list of ID strings for this course's prerequisite courses.
"""
return json.loads(self._pre_requisite_courses_json)
@classmethod
def get_select_courses(cls, course_keys):
"""
Returns CourseOverview objects for the given course_keys.
"""
course_overviews = []
log.info('Generating course overview for %d courses.',
len(course_keys))
log.debug(
'Generating course overview(s) for the following courses: %s',
course_keys)
for course_key in course_keys:
try:
course_overviews.append(CourseOverview.get_from_id(course_key))
except Exception as ex: # pylint: disable=broad-except
log.exception(
'An error occurred while generating course overview for %s: %s',
unicode(course_key),
ex.message,
)
log.info('Finished generating course overviews.')
return course_overviews
@classmethod
def get_all_courses(cls, org=None, filter_=None):
"""
Returns all CourseOverview objects in the database.
Arguments:
org (string): Optional parameter that allows case-insensitive
filtering by organization.
filter_ (dict): Optional parameter that allows custom filtering.
"""
# Note: If a newly created course is not returned in this QueryList,
# make sure the "publish" signal was emitted when the course was
# created. For tests using CourseFactory, use emit_signals=True.
course_overviews = CourseOverview.objects.all()
if org:
# In rare cases, courses belonging to the same org may be accidentally assigned
# an org code with a different casing (e.g., Harvardx as opposed to HarvardX).
# Case-insensitive exact matching allows us to deal with this kind of dirty data.
course_overviews = course_overviews.filter(org__iexact=org)
if filter_:
course_overviews = course_overviews.filter(**filter_)
return course_overviews
@classmethod
def get_all_course_keys(cls):
"""
Returns all course keys from course overviews.
"""
return [
CourseKey.from_string(course_overview['id'])
for course_overview in CourseOverview.objects.values('id')
]
def is_discussion_tab_enabled(self):
"""
Returns True if course has discussion tab and is enabled
"""
tabs = self.tabs.all()
# creates circular import; hence explicitly referenced is_discussion_enabled
for tab in tabs:
if tab.tab_id == "discussion" and django_comment_client.utils.is_discussion_enabled(
self.id):
return True
return False
@property
def image_urls(self):
"""
Return a dict with all known URLs for this course image.
Current resolutions are:
raw = original upload from the user
small = thumbnail with dimensions CourseOverviewImageConfig.current().small
large = thumbnail with dimensions CourseOverviewImageConfig.current().large
If no thumbnails exist, the raw (originally uploaded) image will be
returned for all resolutions.
"""
# This is either the raw image that the course team uploaded, or the
# settings.DEFAULT_COURSE_ABOUT_IMAGE_URL if they didn't specify one.
raw_image_url = self.course_image_url
# Default all sizes to return the raw image if there is no
# CourseOverviewImageSet associated with this CourseOverview. This can
# happen because we're disabled via CourseOverviewImageConfig.
urls = {
'raw': raw_image_url,
'small': raw_image_url,
'large': raw_image_url,
}
# If we do have a CourseOverviewImageSet, we still default to the raw
# images if our thumbnails are blank (might indicate that there was a
# processing error of some sort while trying to generate thumbnails).
if hasattr(
self,
'image_set') and CourseOverviewImageConfig.current().enabled:
urls['small'] = self.image_set.small_url or raw_image_url
urls['large'] = self.image_set.large_url or raw_image_url
return urls
@property
def pacing(self):
""" Returns the pacing for the course.
Potential values:
self: Self-paced courses
instructor: Instructor-led courses
"""
return 'self' if self.self_paced else 'instructor'
def __unicode__(self):
"""Represent ourselves with the course key."""
return unicode(self.id)
class PersistentSubsectionGrade(TimeStampedModel):
"""
A django model tracking persistent grades at the subsection level.
"""
class Meta(object):
unique_together = [
# * Specific grades can be pulled using all three columns,
# * Progress page can pull all grades for a given (course_id, user_id)
# * Course staff can see all grades for a course using (course_id,)
('course_id', 'user_id', 'usage_key'),
]
# primary key will need to be large for this table
id = UnsignedBigIntAutoField(primary_key=True) # pylint: disable=invalid-name
# uniquely identify this particular grade object
user_id = models.IntegerField(blank=False)
course_id = CourseKeyField(blank=False, max_length=255)
# note: the usage_key may not have the run filled in for
# old mongo courses. Use the full_usage_key property
# instead when you want to use/compare the usage_key.
usage_key = UsageKeyField(blank=False, max_length=255)
# Information relating to the state of content when grade was calculated
subtree_edited_timestamp = models.DateTimeField(
'last content edit timestamp', blank=False)
course_version = models.CharField('guid of latest course version',
blank=True,
max_length=255)
# earned/possible refers to the number of points achieved and available to achieve.
# graded refers to the subset of all problems that are marked as being graded.
earned_all = models.FloatField(blank=False)
possible_all = models.FloatField(blank=False)
earned_graded = models.FloatField(blank=False)
possible_graded = models.FloatField(blank=False)
# track which blocks were visible at the time of grade calculation
visible_blocks = models.ForeignKey(VisibleBlocks,
db_column='visible_blocks_hash',
to_field='hashed')
@property
def full_usage_key(self):
"""
Returns the "correct" usage key value with the run filled in.
"""
if self.usage_key.run is None: # pylint: disable=no-member
return self.usage_key.replace(course_key=self.course_id)
else:
return self.usage_key
def __unicode__(self):
"""
Returns a string representation of this model.
"""
return u"{} user: {}, course version: {}, subsection {} ({}). {}/{} graded, {}/{} all".format(
type(self).__name__,
self.user_id,
self.course_version,
self.usage_key,
self.visible_blocks_id,
self.earned_graded,
self.possible_graded,
self.earned_all,
self.possible_all,
)
@classmethod
def read_grade(cls, user_id, usage_key):
"""
Reads a grade from database
Arguments:
user_id: The user associated with the desired grade
usage_key: The location of the subsection associated with the desired grade
Raises PersistentSubsectionGrade.DoesNotExist if applicable
"""
return cls.objects.select_related('visible_blocks').get(
user_id=user_id,
course_id=usage_key.
course_key, # course_id is included to take advantage of db indexes
usage_key=usage_key,
)
@classmethod
def bulk_read_grades(cls, user_id, course_key):
"""
Reads all grades for the given user and course.
Arguments:
user_id: The user associated with the desired grades
course_key: The course identifier for the desired grades
"""
return cls.objects.select_related('visible_blocks').filter(
user_id=user_id,
course_id=course_key,
)
@classmethod
def update_or_create_grade(cls, **kwargs):
"""
Wrapper for objects.update_or_create.
"""
cls._prepare_params_and_visible_blocks(kwargs)
user_id = kwargs.pop('user_id')
usage_key = kwargs.pop('usage_key')
grade, _ = cls.objects.update_or_create(
user_id=user_id,
course_id=usage_key.course_key,
usage_key=usage_key,
defaults=kwargs,
)
return grade
@classmethod
def create_grade(cls, **kwargs):
"""
Wrapper for objects.create.
"""
cls._prepare_params_and_visible_blocks(kwargs)
return cls.objects.create(**kwargs)
@classmethod
def bulk_create_grades(cls, grade_params_iter, course_key):
"""
Bulk creation of grades.
"""
if not grade_params_iter:
return
map(cls._prepare_params, grade_params_iter)
VisibleBlocks.bulk_get_or_create(
[params['visible_blocks'] for params in grade_params_iter],
course_key)
map(cls._prepare_params_visible_blocks_id, grade_params_iter)
return cls.objects.bulk_create([
PersistentSubsectionGrade(**params) for params in grade_params_iter
])
@classmethod
def _prepare_params_and_visible_blocks(cls, params):
"""
Prepares the fields for the grade record, while
creating the related VisibleBlocks, if needed.
"""
cls._prepare_params(params)
params[
'visible_blocks'] = VisibleBlocks.objects.create_from_blockrecords(
params['visible_blocks'])
@classmethod
def _prepare_params(cls, params):
"""
Prepares the fields for the grade record.
"""
if not params.get('course_id', None):
params['course_id'] = params['usage_key'].course_key
params['course_version'] = params.get('course_version', None) or ""
params['visible_blocks'] = BlockRecordList.from_list(
params['visible_blocks'], params['course_id'])
@classmethod
def _prepare_params_visible_blocks_id(cls, params):
"""
Prepares the visible_blocks_id field for the grade record,
using the hash of the visible_blocks field. Specifying
the hashed field eliminates extra queries to get the
VisibleBlocks record. Use this variation of preparing
the params when you are sure of the existence of the
VisibleBlock.
"""
params['visible_blocks_id'] = params['visible_blocks'].hash_value
del params['visible_blocks']
class CourseOverview(django.db.models.Model):
"""
Model for storing and caching basic information about a course.
This model contains basic course metadata such as an ID, display name,
image URL, and any other information that would be necessary to display
a course as part of a user dashboard or enrollment API.
"""
# Course identification
id = CourseKeyField(db_index=True, primary_key=True, max_length=255) # pylint: disable=invalid-name
_location = UsageKeyField(max_length=255)
display_name = TextField(null=True)
display_number_with_default = TextField()
display_org_with_default = TextField()
# Start/end dates
start = DateTimeField(null=True)
end = DateTimeField(null=True)
advertised_start = TextField(null=True)
# URLs
course_image_url = TextField()
facebook_url = TextField(null=True)
social_sharing_url = TextField(null=True)
end_of_course_survey_url = TextField(null=True)
# Certification data
certificates_display_behavior = TextField(null=True)
certificates_show_before_end = BooleanField()
cert_html_view_enabled = BooleanField()
has_any_active_web_certificate = BooleanField()
cert_name_short = TextField()
cert_name_long = TextField()
# Grading
lowest_passing_grade = DecimalField(max_digits=5, decimal_places=2)
# Access parameters
days_early_for_beta = FloatField(null=True)
mobile_available = BooleanField()
visible_to_staff_only = BooleanField()
_pre_requisite_courses_json = TextField() # JSON representation of list of CourseKey strings
@staticmethod
def _create_from_course(course):
"""
Creates a CourseOverview object from a CourseDescriptor.
Does not touch the database, simply constructs and returns an overview
from the given course.
Arguments:
course (CourseDescriptor): any course descriptor object
Returns:
CourseOverview: overview extracted from the given course
"""
from lms.djangoapps.certificates.api import get_active_web_certificate
from lms.djangoapps.courseware.courses import course_image_url
return CourseOverview(
id=course.id,
_location=course.location,
display_name=course.display_name,
display_number_with_default=course.display_number_with_default,
display_org_with_default=course.display_org_with_default,
start=course.start,
end=course.end,
advertised_start=course.advertised_start,
course_image_url=course_image_url(course),
facebook_url=course.facebook_url,
social_sharing_url=course.social_sharing_url,
certificates_display_behavior=course.certificates_display_behavior,
certificates_show_before_end=course.certificates_show_before_end,
cert_html_view_enabled=course.cert_html_view_enabled,
has_any_active_web_certificate=(get_active_web_certificate(course) is not None),
cert_name_short=course.cert_name_short,
cert_name_long=course.cert_name_long,
lowest_passing_grade=course.lowest_passing_grade,
end_of_course_survey_url=course.end_of_course_survey_url,
days_early_for_beta=course.days_early_for_beta,
mobile_available=course.mobile_available,
visible_to_staff_only=course.visible_to_staff_only,
_pre_requisite_courses_json=json.dumps(course.pre_requisite_courses)
)
@staticmethod
def get_from_id(course_id):
"""
Load a CourseOverview object for a given course ID.
First, we try to load the CourseOverview from the database. If it
doesn't exist, we load the entire course from the modulestore, create a
CourseOverview object from it, and then cache it in the database for
future use.
Arguments:
course_id (CourseKey): the ID of the course overview to be loaded.
Returns:
CourseOverview: overview of the requested course. If loading course
from the module store failed, returns None.
Raises:
- CourseOverview.DoesNotExist if the course specified by course_id
was not found.
- IOError if some other error occurs while trying to load the
course from the module store.
"""
course_overview = None
try:
course_overview = CourseOverview.objects.get(id=course_id)
except CourseOverview.DoesNotExist:
store = modulestore()
with store.bulk_operations(course_id):
course = store.get_course(course_id)
if isinstance(course, CourseDescriptor):
course_overview = CourseOverview._create_from_course(course)
course_overview.save()
elif course is not None:
raise IOError(
"Error while loading course {} from the module store: {}",
unicode(course_id),
course.error_msg if isinstance(course, ErrorDescriptor) else unicode(course)
)
else:
raise CourseOverview.DoesNotExist()
return course_overview
def clean_id(self, padding_char='='):
"""
Returns a unique deterministic base32-encoded ID for the course.
Arguments:
padding_char (str): Character used for padding at end of base-32
-encoded string, defaulting to '='
"""
return course_metadata_utils.clean_course_key(self.location.course_key, padding_char)
@property
def location(self):
"""
Returns the UsageKey of this course.
UsageKeyField has a strange behavior where it fails to parse the "run"
of a course out of the serialized form of a Mongo Draft UsageKey. This
method is a wrapper around _location attribute that fixes the problem
by calling map_into_course, which restores the run attribute.
"""
if self._location.run is None:
self._location = self._location.map_into_course(self.id)
return self._location
@property
def number(self):
"""
Returns this course's number.
This is a "number" in the sense of the "course numbers" that you see at
lots of universities. For example, given a course
"Intro to Computer Science" with the course key "edX/CS-101/2014", the
course number would be "CS-101"
"""
return course_metadata_utils.number_for_course_location(self.location)
@property
def url_name(self):
"""
Returns this course's URL name.
"""
return course_metadata_utils.url_name_for_course_location(self.location)
@property
def display_name_with_default(self):
"""
Return reasonable display name for the course.
"""
return course_metadata_utils.display_name_with_default(self)
def has_started(self):
"""
Returns whether the the course has started.
"""
return course_metadata_utils.has_course_started(self.start)
def has_ended(self):
"""
Returns whether the course has ended.
"""
return course_metadata_utils.has_course_ended(self.end)
def start_datetime_text(self, format_string="SHORT_DATE"):
"""
Returns the desired text corresponding the course's start date and
time in UTC. Prefers .advertised_start, then falls back to .start.
"""
return course_metadata_utils.course_start_datetime_text(
self.start,
self.advertised_start,
format_string,
ugettext,
strftime_localized
)
@property
def start_date_is_still_default(self):
"""
Checks if the start date set for the course is still default, i.e.
.start has not been modified, and .advertised_start has not been set.
"""
return course_metadata_utils.course_start_date_is_default(
self.start,
self.advertised_start,
)
def end_datetime_text(self, format_string="SHORT_DATE"):
"""
Returns the end date or datetime for the course formatted as a string.
"""
return course_metadata_utils.course_end_datetime_text(
self.end,
format_string,
strftime_localized
)
def may_certify(self):
"""
Returns whether it is acceptable to show the student a certificate
download link.
"""
return course_metadata_utils.may_certify_for_course(
self.certificates_display_behavior,
self.certificates_show_before_end,
self.has_ended()
)
@property
def pre_requisite_courses(self):
"""
Returns a list of ID strings for this course's prerequisite courses.
"""
return json.loads(self._pre_requisite_courses_json)
