def __iter__(self):
"Note: this method is EXPENSIVE! PLease only use if absolutely needed"
cmp_key = LPCMKey(self.name, 'dummy_key')
result = DynamoDB.query(cmp_key, attributes_to_get=['table', 'key'])
for item in result:
key = item['key']
yield base64.b32decode(key).decode('utf-8')
def atomic_add_value(self, key, value):
cmp_key = LPCMKey(self.name, key)
try:
item = DynamoDB.get_item(cmp_key)
except DynamoDBKeyNotFoundError:
item = DynamoDB.create_item(cmp_key)
item.add_attribute('value', value)
item.save()
def delete(self, key):
"Deletes a key-value map from dynamodb. Ignores it if item does not exist"
cmp_key = LPCMKey(self.name, key)
try:
item = DynamoDB.get_item(cmp_key)
except DynamoDBKeyNotFoundError:
return # delete fails silently
item.delete()
def atomic_delete_values(self, key, values):
"""Deletes a set of values from an item. Fails silently if item does not exist"""
cmp_key = LPCMKey(self.name, key)
try:
item = DynamoDB.get_item(cmp_key)
except DynamoDBKeyNotFoundError:
return # Nothing to do
item.delete_attribute('value', values)
item.save()
def __getitem__(self, key):
cmp_key = LPCMKey(self.name, key)
try:
item = DynamoDB.get_item(cmp_key)
except DynamoDBKeyNotFoundError:
raise KeyError(u"{name}:{key}".format(
name=self.name, key=cmp_key.original_key_obj))
value = item['value']
value = self._postprocess_value_after_ddb_load(value)
return value
def __setitem__(self, key, value):
Signals.pre_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
cmp_key = LPCMKey(self.name, key)
self.cache.set(cmp_key.cache_key, value)
self.lpm[key] = value
Signals.post_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
def _atomic_delete_values(self, key, values):
Signals.pre_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
cmp_key = LPCMKey(self.name, key)
self.lpm.atomic_delete_values(key, values)
self.cache.delete(cmp_key.cache_key)
Signals.post_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
def delete(self, key):
"Deletes a key-value map from memcached and dynamodb. Ignores it if item does not exist"
Signals.pre_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='delete')
cmp_key = LPCMKey(self.name, key)
self.cache.delete(cmp_key.cache_key)
self.lpm.delete(key)
Signals.post_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='delete')
def _atomic_add_value(self, key, value):
Signals.pre_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
cmp_key = LPCMKey(self.name, key)
self.cache.atomic_update(cmp_key.cache_key,
value,
update_operator=operator.add,
default_value=0)
Signals.post_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
def remove_values(self, key, values):
Signals.pre_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
cmp_key = LPCMKey(self.name, key)
self.cache.atomic_update(cmp_key.cache_key,
values,
update_operator=set.difference,
default_value=set())
Signals.post_update.send(sender=self.__class__,
map_name=self.name,
key=key,
action='put')
def __getitem__(self, key):
cmp_key = LPCMKey(self.name, key)
v = self.cache.get(cmp_key.cache_key)
if v is not None:
return v
return self._get_from_dynamodb_and_save_in_cache(cmp_key)
def __setitem__(self, key, value):
cmp_key = LPCMKey(self.name, key)
value = self._preprocess_value_before_ddb_save(value)
item = DynamoDB.create_item(cmp_key)
item['value'] = value
item.put()