Andal.LND/edx-platform
6
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Don't sort blocks to retain order.

Browse Source
This commit is contained in:
Nimisha Asthagiri
2016-09-10 11:27:47 -04:00
parent 660bc8f447
commit d244715e87
2 changed files with 53 additions and 40 deletions
Download Patch File Download Diff File Expand all files Collapse all files

43
lms/djangoapps/grades/models.py
View File

@@ -29,13 +29,16 @@ log = logging.getLogger(__name__)
BlockRecord = namedtuple('BlockRecord', ['locator', 'weight', 'max_score'])
class BlockRecordSet(frozenset):
class BlockRecordList(tuple):
"""
An immutable ordered collection of BlockRecord objects.
An immutable ordered list of BlockRecord objects.
"""
def __init__(self, *args, **kwargs):
super(BlockRecordSet, self).__init__(*args, **kwargs)
def __new__(cls, blocks):
return super(BlockRecordList, cls).__new__(cls, tuple(blocks))
def __init__(self, blocks):
super(BlockRecordList, self).__init__(blocks)
self._json = None
self._hash = None
@@ -56,8 +59,7 @@ class BlockRecordSet(frozenset):
stable ordering.
"""
if self._json is None:
sorted_blocks = sorted(self, key=attrgetter('locator'))
list_of_block_dicts = [block._asdict() for block in sorted_blocks]
list_of_block_dicts = [block._asdict() for block in self]
course_key_string = self._get_course_key_string() # all blocks are from the same course
for block_dict in list_of_block_dicts:
@@ -77,7 +79,7 @@ class BlockRecordSet(frozenset):
@classmethod
def from_json(cls, blockrecord_json):
"""
Return a BlockRecordSet from a json list.
Return a BlockRecordList from a previously serialized json.
"""
data = json.loads(blockrecord_json)
course_key = data['course_key']
@@ -97,6 +99,13 @@ class BlockRecordSet(frozenset):
)
return cls(record_generator)
@classmethod
def from_list(cls, blocks):
"""
Return a BlockRecordList from a list.
"""
return cls(tuple(blocks))
def to_hash(self):
"""
Return a hashed version of the list of block records.
@@ -120,24 +129,18 @@ class VisibleBlocksQuerySet(models.QuerySet):
"""
Creates a new VisibleBlocks model object.
Argument 'blocks' should be a BlockRecordSet.
Argument 'blocks' should be a BlockRecordList.
"""
if not isinstance(blocks, BlockRecordSet):
blocks = BlockRecordSet(blocks)
model, _ = self.get_or_create(hashed=blocks.to_hash(), defaults={'blocks_json': blocks.to_json()})
return model
def hash_from_blockrecords(self, blocks):
"""
Return the hash for a given BlockRecordSet, serializing the records if
Return the hash for a given list of blocks, saving the records if
possible, but returning the hash even if an IntegrityError occurs.
Argument 'blocks' should be a BlockRecordList.
"""
if not isinstance(blocks, BlockRecordSet):
blocks = BlockRecordSet(blocks)
try:
with transaction.atomic():
model = self.create_from_blockrecords(blocks)
@@ -176,7 +179,7 @@ class VisibleBlocks(models.Model):
Returns the blocks_json data stored on this model as a list of
BlockRecords in the order they were provided.
"""
return BlockRecordSet.from_json(self.blocks_json)
return BlockRecordList.from_json(self.blocks_json)
class PersistentSubsectionGradeQuerySet(models.QuerySet):
@@ -204,7 +207,7 @@ class PersistentSubsectionGradeQuerySet(models.QuerySet):
if not kwargs.get('course_id', None):
kwargs['course_id'] = kwargs['usage_key'].course_key
visible_blocks_hash = VisibleBlocks.objects.hash_from_blockrecords(blocks=visible_blocks)
visible_blocks_hash = VisibleBlocks.objects.hash_from_blockrecords(BlockRecordList.from_list(visible_blocks))
return super(PersistentSubsectionGradeQuerySet, self).create(
visible_blocks_id=visible_blocks_hash,
**kwargs
@@ -358,7 +361,7 @@ class PersistentSubsectionGrade(TimeStampedModel):
Modify an existing PersistentSubsectionGrade object, saving the new
version.
"""
visible_blocks_hash = VisibleBlocks.objects.hash_from_blockrecords(blocks=visible_blocks)
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

50
lms/djangoapps/grades/tests/test_models.py
View File

@@ -14,27 +14,27 @@ from opaque_keys.edx.locator import CourseLocator, BlockUsageLocator
from lms.djangoapps.grades.models import (
BlockRecord,
BlockRecordSet,
BlockRecordList,
PersistentSubsectionGrade,
VisibleBlocks
)
class BlockRecordSetTestCase(TestCase):
class BlockRecordListTestCase(TestCase):
"""
Verify the behavior of BlockRecordSets, particularly around edge cases
Verify the behavior of BlockRecordList, particularly around edge cases
"""
empty_json = '{"blocks":[],"course_key":null}'
def test_empty_block_record_set(self):
brs = BlockRecordSet()
brs = BlockRecordList(())
self.assertFalse(brs)
self.assertEqual(
brs.to_json(),
self.empty_json
)
self.assertEqual(
BlockRecordSet.from_json(self.empty_json),
BlockRecordList.from_json(self.empty_json),
brs
)
@@ -108,11 +108,17 @@ class VisibleBlocksTest(GradesModelTestCase):
"""
Test the VisibleBlocks model.
"""
def _create_block_record_list(self, blocks):
"""
Creates and returns a BlockRecordList for the given blocks.
"""
return VisibleBlocks.objects.create_from_blockrecords(BlockRecordList.from_list(blocks))
def test_creation(self):
"""
Happy path test to ensure basic create functionality works as expected.
"""
vblocks = VisibleBlocks.objects.create_from_blockrecords([self.record_a])
vblocks = self._create_block_record_list([self.record_a])
list_of_block_dicts = [self.record_a._asdict()]
for block_dict in list_of_block_dicts:
block_dict['locator'] = unicode(block_dict['locator']) # BlockUsageLocator is not json-serializable
@@ -128,30 +134,34 @@ class VisibleBlocksTest(GradesModelTestCase):
self.assertEqual(expected_json, vblocks.blocks_json)
self.assertEqual(expected_hash, vblocks.hashed)
def test_ordering_does_not_matter(self):
def test_ordering_matters(self):
"""
When creating new vblocks, a different ordering of blocks produces the
same record in the database.
When creating new vblocks, different ordering of blocks produces
different records in the database.
"""
stored_vblocks = VisibleBlocks.objects.create_from_blockrecords([self.record_a, self.record_b])
repeat_vblocks = VisibleBlocks.objects.create_from_blockrecords([self.record_b, self.record_a])
new_vblocks = VisibleBlocks.objects.create_from_blockrecords([self.record_b])
stored_vblocks = self._create_block_record_list([self.record_a, self.record_b])
repeat_vblocks = self._create_block_record_list([self.record_b, self.record_a])
same_order_vblocks = self._create_block_record_list([self.record_a, self.record_b])
new_vblocks = self._create_block_record_list([self.record_b])
self.assertEqual(stored_vblocks.pk, repeat_vblocks.pk)
self.assertEqual(stored_vblocks.hashed, repeat_vblocks.hashed)
self.assertNotEqual(stored_vblocks.pk, repeat_vblocks.pk)
self.assertNotEqual(stored_vblocks.hashed, repeat_vblocks.hashed)
self.assertEquals(stored_vblocks.pk, same_order_vblocks.pk)
self.assertEquals(stored_vblocks.hashed, same_order_vblocks.hashed)
self.assertNotEqual(stored_vblocks.pk, new_vblocks.pk)
self.assertNotEqual(stored_vblocks.hashed, new_vblocks.hashed)
def test_blocks_property(self):
"""
Ensures that, given an array of BlockRecord, creating visible_blocks and accessing
visible_blocks.blocks yields a copy of the initial array. Also, trying to set the blocks property should raise
an exception.
Ensures that, given an array of BlockRecord, creating visible_blocks
and accessing visible_blocks.blocks yields a copy of the initial array.
Also, trying to set the blocks property should raise an exception.
"""
expected_blocks = [self.record_a, self.record_b]
visible_blocks = VisibleBlocks.objects.create_from_blockrecords(expected_blocks)
self.assertEqual(BlockRecordSet(expected_blocks), visible_blocks.blocks)
expected_blocks = (self.record_a, self.record_b)
visible_blocks = self._create_block_record_list(expected_blocks)
self.assertEqual(expected_blocks, visible_blocks.blocks)
with self.assertRaises(AttributeError):
visible_blocks.blocks = expected_blocks