def initialise(keyspace="indigo",
hosts=('127.0.0.1', ),
strategy='SimpleStrategy',
repl_factor=1):
"""Initialise Cassandra connection"""
num_retries = 6
retry_timeout = 1
for retry in xrange(num_retries):
try:
logger.info('Connecting to Cassandra keyspace "{2}" '
'on "{0}" with strategy "{1}"'.format(
hosts, strategy, keyspace))
connection.setup(hosts, keyspace, protocol_version=3)
if strategy is 'SimpleStrategy':
create_keyspace_simple(keyspace, repl_factor, True)
else:
create_keyspace_network_topology(keyspace, {}, True)
break
except dse.cluster.NoHostAvailable:
logger.warning(
'Unable to connect to Cassandra. Retrying in {0} seconds...'.
format(retry_timeout))
time.sleep(retry_timeout)
retry_timeout *= 2
def connect():
"""Connect to a Cassandra cluster.
keyspace, hosts, strategy variables are used to configure the connection.
See the cfg object in the :mod:`radon.model.config` module, .
:return: A boolean which indicates if the connection is successful
:rtype: bool"""
num_retries = 5
retry_timeout = 2
keyspace = cfg.dse_keyspace
hosts = cfg.dse_host
strategy = (cfg.dse_strategy, )
for _ in range(num_retries):
try:
cfg.logger.info('Connecting to Cassandra keyspace "{2}" '
'on "{0}" with strategy "{1}"'.format(
hosts, strategy, keyspace))
profile = ExecutionProfile(
load_balancing_policy=WhiteListRoundRobinPolicy(hosts))
profiles = {EXEC_PROFILE_DEFAULT: profile}
connection.setup(
hosts,
keyspace,
protocol_version=3,
execution_profiles=profiles,
)
return True
except NoHostAvailable:
cfg.logger.warning(
"Unable to connect to Cassandra on {0}. Retrying in {1} seconds..."
.format(hosts, retry_timeout))
time.sleep(retry_timeout)
return False
def setup_connection(keyspace_name):
connection.setup([DSE_IP],
consistency=ConsistencyLevel.ONE,
protocol_version=PROTOCOL_VERSION,
default_keyspace=keyspace_name)
def test_connection_setup_with_setup(self):
connection.setup(hosts=None, default_keyspace=None)
self.assertIsNotNone(
connection.get_connection("default").cluster.metadata.get_host(
"127.0.0.1"))