YugabyteDB Python Driver for YCQL - Yugabyte Db

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Yugabyte Python Driver for YCQL is based on DataStax Python Driver with additional smart driver features.

To use the driver's partition-aware load balancing feature in a YugabyteDB Aeon cluster, applications must be deployed in a VPC that has been peered with the cluster VPC so that they have access to all nodes in the cluster. For more information, refer to Using YCQL drivers with YugabyteDB Aeon.

Install the Yugabyte Python Driver for YCQL

To install the Yugabyte Python Driver for YCQL, run the following command:

$ pip3 install yb-cassandra-driver --install-option="--no-cython"

{{< note title="Note">}} The flag --no-cython is necessary on MacOS Catalina and further MacOS releases to avoid a failure while building the yb-cassandra-driver. {{< /note >}}

Create a sample Python application

Prerequisites

This tutorial assumes that you have:

installed YugabyteDB, created a universe, and are able to interact with it using the YCQL shell. If not, follow the steps in Quick start.

Write the sample Python application

Create a file yb-cql-helloworld.py and copy the following content into it.

python

from cassandra.cluster import Cluster

# Create the cluster connection.
cluster = Cluster(['127.0.0.1'])
session = cluster.connect()

# Create the keyspace.
session.execute('CREATE KEYSPACE IF NOT EXISTS ybdemo;')
print("Created keyspace ybdemo")

# Create the table.
session.execute(
  """
  CREATE TABLE IF NOT EXISTS ybdemo.employee (id int PRIMARY KEY,
                                              name varchar,
                                              age int,
                                              language varchar);
  """)
print("Created table employee")

# Insert a row.
session.execute(
  """
  INSERT INTO ybdemo.employee (id, name, age, language)
  VALUES (1, 'John', 35, 'Python');
  """)
print("Inserted (id, name, age, language) = (1, 'John', 35, 'Python')")

# Query the row.
rows = session.execute('SELECT name, age, language FROM ybdemo.employee WHERE id = 1;')
for row in rows:
  print(row.name, row.age, row.language)

# Close the connection.
cluster.shutdown()

Use SSL

To run the application with SSL, create the cluster connection with additional SSL imports and parameters described as follows:

python

# Include additional imports.
from ssl import SSLContext, PROTOCOL_TLS_CLIENT, CERT_REQUIRED
from cassandra.auth import PlainTextAuthProvider

# Include additional parameters.
ssl_context = SSLContext(PROTOCOL_TLS_CLIENT)
ssl_context.load_verify_locations('path to certs file')
ssl_context.verify_mode = CERT_REQUIRED

# Create the cluster connection.
cluster = Cluster(contact_points=['ip_address'],
    ssl_context=ssl_context,
    ssl_options={'server_hostname': 'ip_address'},
    auth_provider=PlainTextAuthProvider(username='username', password='password'))
session = cluster.connect()

Run the application

To run the application, type the following:

$ python3 yb-cql-helloworld.py

You should see the following output.

output

Created keyspace ybdemo
Created table employee
Inserted (id, name, age, language) = (1, 'John', 35, 'Python')
John 35 Python