How to create Kafka-python producer with ssl configuration

Question

I'm trying to create kafka producer with ssl. I need information on how to set SSL parameters in the constructor, the information provided in kafka-python client is not descriptive enough.

What are the ssl_certfile, ssl_cafile, ssl_keyfile parameters. I'm not sure where to look for these files.

producer = KafkaProducer(bootstrap_servers=kafka_broker,
  value_serializer=lambda v: json.dumps(v).encode('utf-8'),
  security_protocol='SSL',
  api_version=(0,10),
  ssl_cafile='ca-certs.pem',ssl_certfile='server.pem',
  ssl_keyfile='server.pem',ssl_password='xxx')
producer.send('rk976772_topic',{"test":0})

Traceback (most recent call last): File "", line 1, in File "/usr/lib/python2.7/site-packages/kafka/producer/kafka.py", line 543, in send self._wait_on_metadata(topic, self.config['max_block_ms'] / 1000.0) File "/usr/lib/python2.7/site-packages/kafka/producer/kafka.py", line 664, in _wait_on_metadata "Failed to update metadata after %.1f secs." % max_wait) kafka.errors.KafkaTimeoutError: KafkaTimeoutError: Failed to update metadata after 60.0 secs.

Answer 1

I was having this issue as well as many other while trying to configure kafka with SSL or SASL_SSL. I'm posting a full tutorial here in case anyone else runs into the same issues. I am using kafka-python 1.4.6 with kafka 2.2.0 on CentOS 6.

Below are the configurations that worked for me for SASL_SSL using kafka-python client. These configurations can be used for PLAINTEXT and SSL security protocols along with SASL_SSL and SASL_PLAINTEXT.

Bash script to generate key files, CARoot, and self-signed cert for use with SSL:

#!/bin/bash
#Step 1
keytool -keystore server.keystore.jks -alias localhost -validity 365 -keyalg RSA -genkey
#Step 2
openssl req -new -x509 -keyout ca-key -out ca-cert -days 365
keytool -keystore server.truststore.jks -alias CARoot -import -file ca-cert
keytool -keystore client.truststore.jks -alias CARoot -import -file ca-cert
#Step 3
keytool -keystore server.keystore.jks -alias localhost -certreq -file cert-file
openssl x509 -req -CA ca-cert -CAkey ca-key -in cert-file -out cert-signed -days 365 -CAcreateserial -passin pass:admin123
keytool -keystore server.keystore.jks -alias CARoot -import -file ca-cert
keytool -keystore server.keystore.jks -alias localhost -import -file cert-signed

You can then use the following command to extract the CARoot.pem:

keytool -exportcert -alias CARoot -keystore server.keystore.jks -rfc -file CARoot.pem

In my server.properties file I have:

listeners=PLAINTEXT://localhost:9091,SASL_PLAINTEXT://localhost:9092,SSL://localhost:9093,SASL_SSL://localhost:9094
security.protocol=SSL
sasl.enabled.mechanisms=PLAIN
ssl.truststore.location=/var/private/ssl/server.truststore.jks
ssl.truststore.password=admin123
ssl.keystore.location=/var/private/ssl/server.keystore.jks
ssl.keystore.password=admin123
ssl.enabled.protocols=TLSv1.2,TLSv1.1,TLSv1
advertised.listeners=PLAINTEXT://localhost:9091,SASL_PLAINTEXT://localhost:9092,SSL://localhost:9093,SASL_SSL://localhost:9094

In my JAAS configuration file(/etc/kafka/kafka_plain_jaas.conf):

KafkaServer {
org.apache.kafka.common.security.plain.PlainLoginModule required
   username=kafka
   password=kafka-secret
   user_username=password;
};
KafkaClient {
org.apache.kafka.common.security.plain.PlainLoginModule required
  username=username
  password=password;
};

Before starting the Kafka server, need to run the following:

export KAFKA_OPTS="-Djava.security.auth.login.config=/etc/kafka/kafka_plain_jaas.conf"

Python consumer and producer: The ssl_context and api_version are what caused SSL handshake errors to occur for me, leading to a timeout. So I commented those out. (There were some tutorials out there that mentioned to use those.)

from kafka import KafkaConsumer, KafkaProducer
import kafka
import ssl
import logging
logging.basicConfig(level=logging.DEBUG)

try:
    topic = "sendMessage"
    sasl_mechanism = "PLAIN"
    username = "username"
    password = "password"
    security_protocol = "SASL_SSL"

    #context = ssl.create_default_context()
    #context.options &= ssl.OP_NO_TLSv1
    #context.options &= ssl.OP_NO_TLSv1_1

    consumer = KafkaConsumer(topic, bootstrap_servers='localhost:9094',
                              #api_version=(0, 10),
                              security_protocol=security_protocol,
                              #ssl_context=context,
                              ssl_check_hostname=True,
                              ssl_cafile='../keys/CARoot.pem',
                              sasl_mechanism = sasl_mechanism,
                              sasl_plain_username = username,
                              sasl_plain_password = password)
                              #ssl_certfile='../keys/certificate.pem',
                              #ssl_keyfile='../keys/key.pem')#,api_version = (0, 10))

    producer = KafkaProducer(bootstrap_servers='localhost:9094',
                             #api_version=(0, 10),
                             security_protocol=security_protocol,
                             #ssl_context=context,
                             ssl_check_hostname=True,
                             ssl_cafile='../keys/CARoot.pem',
                             sasl_mechanism=sasl_mechanism,
                             sasl_plain_username=username,
                             sasl_plain_password=password)
                              #ssl_certfile='../keys/certificate.pem',
                              #ssl_keyfile='../keys/key.pem')#, api_version = (0,10))
    # Write hello world to test topic
    producer.send(topic, bytes("Hello World SSL"))
    producer.flush()


    for msg in consumer:
        print(msg)


except Exception as e:
    print e