def setUp(self):
# Set up MongoEngine
mongoengine.connect(
db='cachecowtestdb',
host='localhost',
port=27017,
read_preference=ReadPreference.PRIMARY,
)
# Set up Redis
redis_client = redis.Redis(host='localhost',
port=6379,
db=9,
socket_timeout=15)
redis_client.flushdb() # clear the whole db
# Set up MongoCacheCow
self.mongo_cache = MongoCacheCow(redis_client)
# Set up a sample MongoEngine document
class BlogPost(mongoengine.Document):
title = mongoengine.StringField()
likes = mongoengine.IntField()
date_created = mongoengine.DateTimeField()
def summary(self):
return '%s (%d likes)' % (self.title, self.likes)
def save(self):
if not self.date_created:
self.date_created = datetime.datetime.utcnow()
super(BlogPost, self).save()
self.BlogPost = BlogPost
self.BlogPost.drop_collection()
self.BlogPost.objects.create(title='First Title', likes=5)
self.BlogPost.objects.create(title='Second Title', likes=10)
def setUp(self):
# Set up MongoEngine
mongoengine.connect(
db='cachecowtestdb',
host='localhost',
port=27017,
read_preference=ReadPreference.PRIMARY,
)
# Set up Redis
redis_client = redis.Redis(
host='localhost',
port=6379,
db=9,
socket_timeout=15
)
redis_client.flushdb() # clear the whole db
# Set up MongoCacheCow
self.mongo_cache = MongoCacheCow(redis_client)
# Set up a sample MongoEngine document
class BlogPost(mongoengine.Document):
title = mongoengine.StringField()
likes = mongoengine.IntField()
date_created = mongoengine.DateTimeField()
def summary(self):
return '%s (%d likes)' % (self.title, self.likes)
def save(self):
if not self.date_created:
self.date_created = datetime.datetime.utcnow()
super(BlogPost, self).save()
self.BlogPost = BlogPost
self.BlogPost.drop_collection()
self.BlogPost.objects.create(title='First Title', likes=5)
self.BlogPost.objects.create(title='Second Title', likes=10)
class CacheCowTestCase(unittest.TestCase):
def setUp(self):
# Set up MongoEngine
mongoengine.connect(
db='cachecowtestdb',
host='localhost',
port=27017,
read_preference=ReadPreference.PRIMARY,
)
# Set up Redis
redis_client = redis.Redis(host='localhost',
port=6379,
db=9,
socket_timeout=15)
redis_client.flushdb() # clear the whole db
# Set up MongoCacheCow
self.mongo_cache = MongoCacheCow(redis_client)
# Set up a sample MongoEngine document
class BlogPost(mongoengine.Document):
title = mongoengine.StringField()
likes = mongoengine.IntField()
date_created = mongoengine.DateTimeField()
def summary(self):
return '%s (%d likes)' % (self.title, self.likes)
def save(self):
if not self.date_created:
self.date_created = datetime.datetime.utcnow()
super(BlogPost, self).save()
self.BlogPost = BlogPost
self.BlogPost.drop_collection()
self.BlogPost.objects.create(title='First Title', likes=5)
self.BlogPost.objects.create(title='Second Title', likes=10)
def test_get_db_queries(self):
"""
Make sure consecutive calls to mongo_cache.get don't hit the database
for the same doc.
"""
with query_counter() as q:
for i in range(3):
self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.mongo_cache.get(self.BlogPost, 'title', 'Second Title')
# Only 2 queries to Mongo should be performed - one for caching
# First Title and one for Second Title
self.assertEqual(q, 2)
def test_get_doc_consistency(self):
"""
Make sure the doc fetched from Mongo doesn't differ from the cached
doc fetched from Redis.
"""
db_obj = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
cached_obj = self.mongo_cache.get(self.BlogPost, 'title',
'First Title')
self.assertEqual(db_obj.pk, cached_obj.pk)
self.assertEqual(db_obj.title, cached_obj.title)
self.assertEqual(db_obj.likes, cached_obj.likes)
self.assertTrue(isinstance(db_obj.date_created, datetime.datetime))
self.assertTrue(isinstance(cached_obj.date_created, datetime.datetime))
self.assertEqual(db_obj.date_created,
cached_obj.date_created.replace(tzinfo=None)
) # bson parsing unfortunately includes the tz offset
self.assertEqual(db_obj.summary(), cached_obj.summary())
self.assertEqual(cached_obj.summary(), 'First Title (5 likes)')
def test_invalidate(self):
"""Make sure simple cache invalidation works."""
with query_counter() as q:
self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.mongo_cache.invalidate(self.BlogPost, 'title', 'First Title')
bp = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.mongo_cache.invalidate(bp.__class__, 'title', bp.title)
self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.assertEqual(q, 3)
def test_collision(self):
"""
Make sure that the right object is returned, even in case of a hash
collision.
"""
faux_obj = self.BlogPost.objects.get(title='Second Title')
with query_counter() as q:
obj1 = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
# manually override the data in First Post's cache_key to point to
# the Second Title's object, simulating a collision
cache_key, flag_key = self.mongo_cache.get_keys(
self.BlogPost, 'title', 'First Title')
self.mongo_cache.redis.set(cache_key,
self.mongo_cache.serialize(faux_obj))
obj2 = self.mongo_cache.get(
self.BlogPost, 'title', 'First Title'
) # this should return the valid obj and invalidate the cache
obj3 = self.mongo_cache.get(
self.BlogPost, 'title',
'First Title') # this should cache the right obj
obj4 = self.mongo_cache.get(
self.BlogPost, 'title',
'First Title') # this should already have the valid obj cached
self.assertEqual(obj1, obj2)
self.assertEqual(obj1, obj3)
self.assertEqual(obj1, obj4)
self.assertEqual(
q, 3
) # 1st query + query after a cache collision + query that cached the right obj
class CacheCowTestCase(unittest.TestCase):
def setUp(self):
# Set up MongoEngine
mongoengine.connect(
db='cachecowtestdb',
host='localhost',
port=27017,
read_preference=ReadPreference.PRIMARY,
)
# Set up Redis
redis_client = redis.Redis(
host='localhost',
port=6379,
db=9,
socket_timeout=15
)
redis_client.flushdb() # clear the whole db
# Set up MongoCacheCow
self.mongo_cache = MongoCacheCow(redis_client)
# Set up a sample MongoEngine document
class BlogPost(mongoengine.Document):
title = mongoengine.StringField()
likes = mongoengine.IntField()
date_created = mongoengine.DateTimeField()
def summary(self):
return '%s (%d likes)' % (self.title, self.likes)
def save(self):
if not self.date_created:
self.date_created = datetime.datetime.utcnow()
super(BlogPost, self).save()
self.BlogPost = BlogPost
self.BlogPost.drop_collection()
self.BlogPost.objects.create(title='First Title', likes=5)
self.BlogPost.objects.create(title='Second Title', likes=10)
def test_get_db_queries(self):
"""
Make sure consecutive calls to mongo_cache.get don't hit the database
for the same doc.
"""
with query_counter() as q:
for i in range(3):
self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.mongo_cache.get(self.BlogPost, 'title', 'Second Title')
# Only 2 queries to Mongo should be performed - one for caching
# First Title and one for Second Title
self.assertEqual(q, 2)
def test_get_doc_consistency(self):
"""
Make sure the doc fetched from Mongo doesn't differ from the cached
doc fetched from Redis.
"""
db_obj = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
cached_obj = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.assertEqual(db_obj.pk, cached_obj.pk)
self.assertEqual(db_obj.title, cached_obj.title)
self.assertEqual(db_obj.likes, cached_obj.likes)
self.assertTrue(isinstance(db_obj.date_created, datetime.datetime))
self.assertTrue(isinstance(cached_obj.date_created, datetime.datetime))
self.assertEqual(db_obj.date_created, cached_obj.date_created.replace(tzinfo=None)) # bson parsing unfortunately includes the tz offset
self.assertEqual(db_obj.summary(), cached_obj.summary())
self.assertEqual(cached_obj.summary(), 'First Title (5 likes)')
def test_invalidate(self):
"""Make sure simple cache invalidation works."""
with query_counter() as q:
self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.mongo_cache.invalidate(self.BlogPost, 'title', 'First Title')
bp = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.mongo_cache.invalidate(bp.__class__, 'title', bp.title)
self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
self.assertEqual(q, 3)
def test_collision(self):
"""
Make sure that the right object is returned, even in case of a hash
collision.
"""
faux_obj = self.BlogPost.objects.get(title='Second Title')
with query_counter() as q:
obj1 = self.mongo_cache.get(self.BlogPost, 'title', 'First Title')
# manually override the data in First Post's cache_key to point to
# the Second Title's object, simulating a collision
cache_key, flag_key = self.mongo_cache.get_keys(
self.BlogPost,'title', 'First Title'
)
self.mongo_cache.redis.set(
cache_key,
self.mongo_cache.serialize(faux_obj)
)
obj2 = self.mongo_cache.get(self.BlogPost, 'title', 'First Title') # this should return the valid obj and invalidate the cache
obj3 = self.mongo_cache.get(self.BlogPost, 'title', 'First Title') # this should cache the right obj
obj4 = self.mongo_cache.get(self.BlogPost, 'title', 'First Title') # this should already have the valid obj cached
self.assertEqual(obj1, obj2)
self.assertEqual(obj1, obj3)
self.assertEqual(obj1, obj4)
self.assertEqual(q, 3) # 1st query + query after a cache collision + query that cached the right obj
