def open_db(self, keyspace_init=None, reuse_keyspace=True):
cluster = Cluster() # Cluster([self.host], port=self.port)
cluster.connect_timeout = 20
try:
self.session = cluster.connect()
except cassandra.cluster.NoHostAvailable:
print "Ensure an instantiation of Cassandra is running."
sys.exit()
if reuse_keyspace:
try:
self.session.execute("USE {}".format(self.keyspace))
except (cassandra.InvalidRequest, ConfigurationException):
print "Keyspace: '{}' does not exists, creating the keyspace.".format(self.keyspace)
self.create_keyspace(keyspace_init)
time.sleep(0.5) # Sleep half a second.
self.session.execute("USE {}".format(self.keyspace))
else:
try:
self.session.execute("DROP KEYSPACE {};".format(self.keyspace), timeout=60)
except (cassandra.InvalidRequest, ConfigurationException):
print "Keyspace: '{}' does not exists, creating the keyspace.".format(self.keyspace)
self.create_keyspace(keyspace_init)
time.sleep(0.5) # Sleep half a second.
self.session.execute("USE {}".format(self.keyspace))
return self.session
from cassandra.policies import ConstantReconnectionPolicy, DCAwareRoundRobinPolicy
from json import dumps
from kafka import KafkaProducer
import time
import io
import socket
# $ sudo pip install python-dateutil
cluster = Cluster(
contact_points=['192.168.1.233', '192.168.1.77', '192.168.1.27'],
idle_heartbeat_interval=5,
load_balancing_policy=DCAwareRoundRobinPolicy(),
reconnection_policy=ConstantReconnectionPolicy(delay=5, max_attempts=50),
idle_heartbeat_timeout=5)
cluster.connect_timeout = 30
session = cluster.connect('temperature')
sleep_time = 1 #in seconds
# pip install kafka-python
producer = KafkaProducer(bootstrap_servers=['192.168.1.167:9092'],
value_serializer=lambda x: dumps(x).encode('utf-8'))
# test
# /test
# main endless loop
while True:
