cassandra_vs_mariadb/cassandra_setup.py

80 lines
2.4 KiB
Python

"""
Python by Techfossguru
Copyright (C) 2017 Satish Prasad
"""
import logging
from cassandra.cluster import Cluster, BatchStatement
class PythonCassandraExample:
def __init__(self):
self.cluster = None
self.session = None
self.keyspace = None
self.log = None
def __del__(self):
self.cluster.shutdown()
def createsession(self):
self.cluster = Cluster(['localhost'])
self.session = self.cluster.connect(self.keyspace)
def getsession(self):
return self.session
# How about Adding some log info to see what went wrong
def setlogger(self):
log = logging.getLogger()
log.setLevel('INFO')
handler = logging.StreamHandler()
handler.setFormatter(logging.Formatter(
"%(asctime)s [%(levelname)s] %(name)s: %(message)s"))
log.addHandler(handler)
self.log = log
# Create Keyspace based on Given Name
def createkeyspace(self, keyspace):
"""
:param keyspace: The Name of Keyspace to be created
:return:
"""
# Before we create new lets check if exiting keyspace; we will drop
# that and create new
rows = self.session.execute(
"SELECT keyspace_name FROM system_schema.keyspaces")
if keyspace in [row[0] for row in rows]:
self.log.info("dropping existing keyspace...")
self.session.execute("DROP KEYSPACE " + keyspace)
self.log.info("creating keyspace...")
self.session.execute("""
CREATE KEYSPACE %s
WITH replication = { 'class': 'SimpleStrategy', 'replication_factor': '2' }
""" % keyspace)
self.log.info("setting keyspace...")
self.session.set_keyspace(keyspace)
def create_table(self):
c_sql = """
CREATE TABLE IF NOT EXISTS employee (emp_id int PRIMARY KEY,
ename varchar,
sal double,
city varchar);
"""
self.session.execute(c_sql)
self.log.info("Employee Table Created !!!")
# lets do some batch insert
if __name__ == '__main__':
example1 = PythonCassandraExample()
example1.createsession()
example1.setlogger()
example1.createkeyspace('techfossguru')
example1.create_table()
example1.insert_data()
example1.select_data()