1mM8hvvw

1import logging
2import time
3from cassandra import ConsistencyLevel
4from cassandra.cluster import Cluster, BatchStatement
5from cassandra.query import SimpleStatement
6from cassandra.auth import PlainTextAuthProvider
7
8class PythonCassandraExample:
9
10    def __init__(self):
11        self.cluster = None
12        self.session = None
13        self.keyspace = None
14        self.log = None
15
16    def __del__(self):
17        self.cluster.shutdown()
18
19    def createsession(self):
20        auth_provider = PlainTextAuthProvider(username='cassandra', password='cassandra')
21        self.cluster = Cluster(['10.220.151.138'],auth_provider = auth_provider)
22        self.session = self.cluster.connect(self.keyspace)
23
24    def getsession(self):
25        return self.session
26
27    # How about Adding some log info to see what went wrong
28    def setlogger(self):
29        log = logging.getLogger()
30        log.setLevel('INFO')
31        handler = logging.StreamHandler()
32        handler.setFormatter(logging.Formatter("%(asctime)s [%(levelname)s] %(name)s: %(message)s"))
33        log.addHandler(handler)
34        self.log = log
35
36    # Create Keyspace based on Given Name
37    def createkeyspace(self, keyspace):
38        """
39        :param keyspace:  The Name of Keyspace to be created
40        :return:
41        """
42        # Before we create new lets check if exiting keyspace; we will drop that and create new
43        rows = self.session.execute("SELECT keyspace_name FROM system_schema.keyspaces")
44        if keyspace in [row[0] for row in rows]:
45            self.log.info("dropping existing keyspace...")
46            self.session.execute("DROP KEYSPACE " + keyspace)
47
48        self.log.info("creating keyspace...")
49        self.session.execute("""
50                CREATE KEYSPACE %s
51                WITH replication = { 'class': 'SimpleStrategy', 'replication_factor': '2' }
52                """ % keyspace)
53
54        self.log.info("setting keyspace...")
55        self.session.set_keyspace(keyspace)
56
57    def create_table(self):
58        c_sql = """
59                CREATE TABLE IF NOT EXISTS employee (emp_id int PRIMARY KEY,
60                                              ename varchar,
61                                              sal double,
62                                              city varchar);
63                 """
64        self.session.execute(c_sql)
65        self.log.info("Employee Table Created !!!")
66
67    # lets do some batch insert
68    def insert_data(self):
69        i = 1
70        while i < 1000000:
71          insert_sql = self.session.prepare("INSERT INTO  employee (emp_id, ename , sal,city) VALUES (?,?,?,?)")
72          batch = BatchStatement()
73          batch.add(insert_sql, (i, 'Danny', 2555, 'De-vito'))
74          self.session.execute(batch)
75          # self.log.info('Batch Insert Completed for ' + str(i))
76          i += 1
77
78    # def select_data(self):
79    #    rows = self.session.execute('select count(*) from perftest.employee limit 5;')
80    #    for row in rows:
81    #        print(row.ename, row.sal)
82
83    def update_data(self):
84        pass
85
86    def delete_data(self):
87        pass
88
89
90if __name__ == '__main__':
91    example1 = PythonCassandraExample()
92    example1.createsession()
93    example1.setlogger()
94    example1.createkeyspace('perftest')
95    example1.create_table()
96
97    # Populate perftest.employee table
98    start = time.time()
99    example1.insert_data()
100    end = time.time()
101    print ('Duration: ' + str(end-start) + ' sec.')
102
103    # example1.select_data()