def _get_or_create_student_item(student_item_dict):
"""Gets or creates a Student Item that matches the values specified.
Attempts to get the specified Student Item. If it does not exist, the
specified parameters are validated, and a new Student Item is created.
Args:
student_item_dict (dict): The dict containing the student_id, item_id,
course_id, and item_type that uniquely defines a student item.
Returns:
StudentItem: The student item that was retrieved or created.
Raises:
SubmissionInternalError: Thrown if there was an internal error while
attempting to create or retrieve the specified student item.
SubmissionRequestError: Thrown if the given student item parameters fail
validation.
Examples:
>>> student_item_dict = dict(
>>> student_id="Tim",
>>> item_id="item_1",
>>> course_id="course_1",
>>> item_type="type_one"
>>> )
>>> _get_or_create_student_item(student_item_dict)
{'item_id': 'item_1', 'item_type': 'type_one', 'course_id': 'course_1', 'student_id': 'Tim'}
"""
try:
try:
return StudentItem.objects.get(**student_item_dict)
except StudentItem.DoesNotExist:
student_item_serializer = StudentItemSerializer(
data=student_item_dict
)
if not student_item_serializer.is_valid():
logger.error(
u"Invalid StudentItemSerializer: errors:{} data:{}".format(
student_item_serializer.errors,
student_item_dict
)
)
raise SubmissionRequestError(field_errors=student_item_serializer.errors)
return student_item_serializer.save()
except DatabaseError:
error_message = u"An error occurred creating student item: {}".format(
student_item_dict
)
logger.exception(error_message)
raise SubmissionInternalError(error_message)
def _get_or_create_student_item(student_item_dict):
"""Gets or creates a Student Item that matches the values specified.
Attempts to get the specified Student Item. If it does not exist, the
specified parameters are validated, and a new Student Item is created.
Args:
student_item_dict (dict): The dict containing the student_id, item_id,
course_id, and item_type that uniquely defines a student item.
Returns:
StudentItem: The student item that was retrieved or created.
Raises:
SubmissionInternalError: Thrown if there was an internal error while
attempting to create or retrieve the specified student item.
SubmissionRequestError: Thrown if the given student item parameters fail
validation.
Examples:
>>> student_item_dict = dict(
>>> student_id="Tim",
>>> item_id="item_1",
>>> course_id="course_1",
>>> item_type="type_one"
>>> )
>>> _get_or_create_student_item(student_item_dict)
{'item_id': 'item_1', 'item_type': 'type_one', 'course_id': 'course_1', 'student_id': 'Tim'}
"""
try:
try:
return StudentItem.objects.get(**student_item_dict)
except StudentItem.DoesNotExist as student_error:
student_item_serializer = StudentItemSerializer(
data=student_item_dict
)
if not student_item_serializer.is_valid():
logger.error(
"Invalid StudentItemSerializer: errors:%(errors)s data:%(data)s",
{
'errors': student_item_serializer.errors,
'data': student_item_dict,
}
)
raise SubmissionRequestError(field_errors=student_item_serializer.errors) from student_error
return student_item_serializer.save()
except DatabaseError as error:
error_message = f"An error occurred creating student item: {student_item_dict}"
logger.exception(error_message)
raise SubmissionInternalError(error_message) from error
def get_course_item_submissions(course_id,
item_id,
item_type,
read_replica=True):
submission_qs = Submission.objects
if read_replica:
submission_qs = _use_read_replica(submission_qs)
query = submission_qs.select_related(
'student_item__scoresummary__latest__submission').filter(
student_item__course_id=course_id,
student_item__item_type=item_type,
student_item__item_id=item_id,
).iterator()
for submission in query:
student_item = submission.student_item
serialized_score = {}
if hasattr(student_item, 'scoresummary'):
latest_score = student_item.scoresummary.latest
if (not latest_score.is_hidden()
) and latest_score.submission.uuid == submission.uuid:
serialized_score = ScoreSerializer(latest_score).data
yield (StudentItemSerializer(student_item).data,
SubmissionSerializer(submission).data, serialized_score)
def get_all_course_submission_information(course_id,
item_type,
read_replica=True):
""" For the given course, get all student items of the given item type, all the submissions for those itemes,
and the latest scores for each item. If a submission was given a score that is not the latest score for the
relevant student item, it will still be included but without score.
Args:
course_id (str): The course that we are getting submissions from.
item_type (str): The type of items that we are getting submissions for.
read_replica (bool): Try to use the database's read replica if it's available.
Yields:
A tuple of three dictionaries representing:
(1) a student item with the following fields:
student_id
course_id
student_item
item_type
(2) a submission with the following fields:
student_item
attempt_number
submitted_at
created_at
answer
(3) a score with the following fields, if one exists and it is the latest score:
(if both conditions are not met, an empty dict is returned here)
student_item
submission
points_earned
points_possible
created_at
submission_uuid
"""
submission_qs = Submission.objects
if read_replica:
submission_qs = _use_read_replica(submission_qs)
query = submission_qs.select_related(
'student_item__scoresummary__latest__submission').filter(
student_item__course_id=course_id,
student_item__item_type=item_type,
).iterator()
for submission in query:
student_item = submission.student_item
serialized_score = {}
if hasattr(student_item, 'scoresummary'):
latest_score = student_item.scoresummary.latest
# Only include the score if it is not a reset score (is_hidden), and if the current submission is the same
# as the student_item's latest score's submission. This matches the behavior of the API's get_score method.
if (not latest_score.is_hidden()
) and latest_score.submission.uuid == submission.uuid:
serialized_score = ScoreSerializer(latest_score).data
yield (StudentItemSerializer(student_item).data,
SubmissionSerializer(submission).data, serialized_score)
def get_submission_and_student(uuid, read_replica=False):
"""
Retrieve a submission by its unique identifier, including the associated student item.
Args:
uuid (str): the unique identifier of the submission.
Kwargs:
read_replica (bool): If true, attempt to use the read replica database.
If no read replica is available, use the default database.
Returns:
Serialized Submission model (dict) containing a serialized StudentItem model
Raises:
SubmissionNotFoundError: Raised if the submission does not exist.
SubmissionRequestError: Raised if the search parameter is not a string.
SubmissionInternalError: Raised for unknown errors.
"""
# This may raise API exceptions
submission = get_submission(uuid, read_replica=read_replica)
# Retrieve the student item from the cache
cache_key = "submissions.student_item.{}".format(
submission['student_item'])
try:
cached_student_item = cache.get(cache_key)
except Exception: # pylint: disable=broad-except
# The cache backend could raise an exception
# (for example, memcache keys that contain spaces)
logger.exception(
"Error occurred while retrieving student item from the cache")
cached_student_item = None
if cached_student_item is not None:
submission['student_item'] = cached_student_item
else:
# There is probably a more idiomatic way to do this using the Django REST framework
try:
student_item_qs = StudentItem.objects
if read_replica:
student_item_qs = _use_read_replica(student_item_qs)
student_item = student_item_qs.get(id=submission['student_item'])
submission['student_item'] = StudentItemSerializer(
student_item).data
cache.set(cache_key, submission['student_item'])
except Exception as ex:
err_msg = f"Could not get submission due to error: {ex}"
logger.exception(err_msg)
raise SubmissionInternalError(err_msg) from ex
return submission
def get_submission_and_student(uuid):
"""
Retrieve a submission by its unique identifier, including the associated student item.
Args:
uuid (str): the unique identifier of the submission.
Returns:
Serialized Submission model (dict) containing a serialized StudentItem model
Raises:
SubmissionNotFoundError: Raised if the submission does not exist.
SubmissionRequestError: Raised if the search parameter is not a string.
SubmissionInternalError: Raised for unknown errors.
"""
# This may raise API exceptions
submission = get_submission(uuid)
# Retrieve the student item from the cache
cache_key = "submissions.student_item.{}".format(
submission['student_item'])
try:
cached_student_item = cache.get(cache_key)
except:
# The cache backend could raise an exception
# (for example, memcache keys that contain spaces)
logger.exception(
"Error occurred while retrieving student item from the cache")
cached_student_item = None
if cached_student_item is not None:
submission['student_item'] = cached_student_item
else:
# There is probably a more idiomatic way to do this using the Django REST framework
try:
student_item = StudentItem.objects.get(
id=submission['student_item'])
submission['student_item'] = StudentItemSerializer(
student_item).data
cache.set(cache_key, submission['student_item'])
except Exception as ex:
err_msg = "Could not get submission due to error: {}".format(ex)
logger.exception(err_msg)
raise SubmissionInternalError(err_msg)
return submission
