The Pulsar Python client


The Pulsar Python client library is a wrapper over the existing C++ client library and exposes all of the same features. You can find the code in the python subdirectory of the C++ client code.

Installation

You can install the pulsar-client library either using pip or by building the library from source.

To install using pip:

$ pip install pulsar-client

To install by building from source, follow the instructions and compile the Pulsar C++ client library. That will also build the Python binding for the library.

To install the built Python bindings:

$ git clone https://github.com/apache/pulsar
$ cd pulsar/pulsar-client-cpp/python
$ sudo python setup.py install

Currently, the only supported Python version is 2.7.

API Reference

The complete Python API reference is available at api/python

Examples

Below you’ll find a variety of Python code examples for the pulsar-client library.

Producer example

This would create a Python producer for the persistent://sample/standalone/ns/my-topic topic and send 10 messages on that topic:

import pulsar

client = pulsar.Client('pulsar://localhost:6650')

producer = client.create_producer(
                'persistent://sample/standalone/ns/my-topic')

for i in range(10):
    producer.send('Hello-%d' % i)

client.close()

Consumer example

This would create a consumer with the my-sub subscription on the persistent://sample/standalone/ns/my-topic topic, listen for incoming messages, print the content and ID of messages that arrive, and acknowledge each message to the Pulsar broker:

import pulsar

client = pulsar.Client('pulsar://localhost:6650')
consumer = client.subscribe(
        'persistent://sample/standalone/ns/my-topic',
        'my-sub')

while True:
    msg = consumer.receive()
    print("Received message '%s' id='%s'", msg.data(), msg.message_id())
    consumer.acknowledge(msg)

client.close()

Async producer example

This would create a Pulsar producer that sends messages asynchronously and triggers the send_callback callback function whenever messages are acknowledged by the broker:

import pulsar

client = pulsar.Client('pulsar://localhost:6650')

producer = client.create_producer(
                'persistent://sample/standalone/ns/my-topic',
                block_if_queue_full=True,
                batching_enabled=True,
                batching_max_publish_delay_ms=10
            )

def send_callback(res, msg):
    print('Message published res=%s', res)

while True:
    producer.send_async('Hello-%d' % i, send_callback)

client.close()