Start a standalone cluster with Docker

For local development and testing, you can run Pulsar in standalone mode on your own machine within a Docker container.

If you have not installed Docker, download it following the instructions for your OS.

Start Pulsar inside Docker

$ docker run -it \
  -p 6650:6650 \
  -p 8080:8080 \
  -v $PWD/data:/pulsar/data \
  apachepulsar/pulsar:2.3.1 \
  bin/pulsar standalone

For Windows, enter something like the following docker command:

$ docker run -it \
  -p 6650:6650 \
  -p 8080:8080 \
  -v "$PWD/data:/pulsar/data".ToLower() \
  apachepulsar/pulsar:2.3.1 \
  bin/pulsar standalone

A few things to note about this command:

• $PWD/data : The docker host directory in Windows operating system must be lowercase.$PWD/data provides you with the specified directory, for example: E:/data.
• -v $PWD/data:/pulsar/data: This makes the process inside the container to store the data and metadata in the filesystem outside the container, in order not to start "fresh" every time the container is restarted.

If you start Pulsar successfully, you will see INFO-level log messages like this:

2017-08-09 22:34:04,030 - INFO  - [main:WebService@213] - Web Service started at http://127.0.0.1:8080
2017-08-09 22:34:04,038 - INFO  - [main:PulsarService@335] - messaging service is ready, bootstrap service on port=8080, broker url=pulsar://127.0.0.1:6650, cluster=standalone, configs=org.apache.pulsar.broker.ServiceConfiguration@4db60246
...

Automatically created namespace

When you start a local standalone cluster, a public/default namespace is created automatically. The namespace is used for development purposes. All Pulsar topics are managed within namespaces. For more information, see Topics.

Start publishing and consuming messages

Pulsar offers client libraries for Java, Go, Python and C++. If you're running a local standalone cluster, you can use one of these root URLs to interact with your cluster:

• pulsar://localhost:6650
• http://localhost:8080

The following example will guide you get started with Pulsar quickly by using the Python client API.

Install the Pulsar Python client library directly from PyPI:

$ pip install pulsar-client

Create a consumer and subscribe to the topic:

import pulsar

client = pulsar.Client('pulsar://localhost:6650')
consumer = client.subscribe('my-topic',
                            subscription_name='my-sub')

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

client.close()

Now start a producer to send some test messages:

import pulsar

client = pulsar.Client('pulsar://localhost:6650')
producer = client.create_producer('my-topic')

for i in range(10):
    producer.send(('hello-pulsar-%d' % i).encode('utf-8'))

client.close()

Get the topic statistics

In Pulsar, you can use REST, Java, or command-line tools to control every aspect of the system. For details on APIs, refer to Admin API Overview.

In the simplest example, you can use curl to probe the stats for a particular topic:

$ curl http://localhost:8080/admin/v2/persistent/public/default/my-topic/stats | python -m json.tool

The output is something like this:

{
  "averageMsgSize": 0.0,
  "msgRateIn": 0.0,
  "msgRateOut": 0.0,
  "msgThroughputIn": 0.0,
  "msgThroughputOut": 0.0,
  "publishers": [
    {
      "address": "/172.17.0.1:35048",
      "averageMsgSize": 0.0,
      "clientVersion": "1.19.0-incubating",
      "connectedSince": "2017-08-09 20:59:34.621+0000",
      "msgRateIn": 0.0,
      "msgThroughputIn": 0.0,
      "producerId": 0,
      "producerName": "standalone-0-1"
    }
  ],
  "replication": {},
  "storageSize": 16,
  "subscriptions": {
    "my-sub": {
      "blockedSubscriptionOnUnackedMsgs": false,
      "consumers": [
        {
          "address": "/172.17.0.1:35064",
          "availablePermits": 996,
          "blockedConsumerOnUnackedMsgs": false,
          "clientVersion": "1.19.0-incubating",
          "connectedSince": "2017-08-09 21:05:39.222+0000",
          "consumerName": "166111",
          "msgRateOut": 0.0,
          "msgRateRedeliver": 0.0,
          "msgThroughputOut": 0.0,
          "unackedMessages": 0
        }
      ],
      "msgBacklog": 0,
      "msgRateExpired": 0.0,
      "msgRateOut": 0.0,
      "msgRateRedeliver": 0.0,
      "msgThroughputOut": 0.0,
      "type": "Exclusive",
      "unackedMessages": 0
    }
  }
}