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id: version-2.4.1-security-token-client title: Client Authentication using tokens sidebar_label: Client Authentication using tokens original_id: security-token-client

Token Authentication Overview

Pulsar supports authenticating clients using security tokens that are based on JSON Web Tokens (RFC-7519).

You can use tokens to identify a Pulsar client and associate with some “principal” (or “role”) that is permitted to do some actions (for example, publish messages to a topic or consume messages from a topic).

The administrator (or some automated service) typically gives a user a token string.

The compact representation of a signed JWT is a string that looks like as the following:

eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJKb2UifQ.ipevRNuRP6HflG8cFKnmUPtypruRC4fb1DWtoLL62SY

Application specifies the token when you are creating the client instance. An alternative is to pass a “token supplier” (a function that returns the token when the client library needs one).

See Token authentication admin for a reference on how to enable token authentication on a Pulsar cluster.

CLI tools

Command-line tools like pulsar-admin, pulsar-perf, and pulsar-client use the conf/client.conf config file in a Pulsar installation.

You need to add the following parameters to that file to use the token authentication with CLI tools of Pulsar:

webServiceUrl=http://broker.example.com:8080/
brokerServiceUrl=pulsar://broker.example.com:6650/
authPlugin=org.apache.pulsar.client.impl.auth.AuthenticationToken
authParams=token:eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJKb2UifQ.ipevRNuRP6HflG8cFKnmUPtypruRC4fb1DWtoLL62SY

The token string can also be read from a file, eg:

authParams=file:///path/to/token/file

Java client

PulsarClient client = PulsarClient.builder()
    .serviceUrl("pulsar://broker.example.com:6650/")
    .authentication(
        AuthenticationFactory.token("eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJKb2UifQ.ipevRNuRP6HflG8cFKnmUPtypruRC4fb1DWtoLL62SY")
    .build();

Similarly, one can also pass a Supplier:

PulsarClient client = PulsarClient.builder()
    .serviceUrl("pulsar://broker.example.com:6650/")
    .authentication(
        AuthenticationFactory.token(() -> {
            // Read token from custom source
            return readToken();
        })
    .build();

Python client

from pulsar import Client, AuthenticationToken

client = Client('pulsar://broker.example.com:6650/'
                authentication=AuthenticationToken('eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJKb2UifQ.ipevRNuRP6HflG8cFKnmUPtypruRC4fb1DWtoLL62SY'))

Alternatively, with a supplier:

def read_token():
    with open('/path/to/token.txt') as tf:
        return tf.read().strip()

client = Client('pulsar://broker.example.com:6650/'
                authentication=AuthenticationToken(read_token))

Go client

client, err := NewClient(ClientOptions{
	URL:            "pulsar://localhost:6650",
	Authentication: NewAuthenticationToken("eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJKb2UifQ.ipevRNuRP6HflG8cFKnmUPtypruRC4fb1DWtoLL62SY"),
})

Alternatively, with a supplier:

client, err := NewClient(ClientOptions{
	URL:            "pulsar://localhost:6650",
	Authentication: NewAuthenticationTokenSupplier(func () string {
        // Read token from custom source
		return readToken()
	}),
})

C++ client

#include <pulsar/Client.h>

pulsar::ClientConfiguration config;
config.setAuth(pulsar::AuthToken::createWithToken("eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJKb2UifQ.ipevRNuRP6HflG8cFKnmUPtypruRC4fb1DWtoLL62SY"));

pulsar::Client client("pulsar://broker.example.com:6650/", config);