Properties file of the Kafka configuration

 

Kafka  property  file 

 A Kafka property file is a configuration file used to configure Apache Kafka, an open-source distributed event streaming platform. It is a text file that contains key-value pairs, where each key represents a Kafka configuration property and its corresponding value specifies the setting for that property.

Here is an example of a Kafka property file:

# General Kafka configurations

broker.id=0

num.network.threads=3

num.io.threads=8

socket.send.buffer.bytes=102400

socket.receive.buffer.bytes=102400

socket.request.max.bytes=104857600

# Zookeeper configurations

zookeeper.connect=localhost:2181

zookeeper.connection.timeout.ms=6000

# Topic configurations

num.partitions=3

default.replication.factor=2

min.insync.replicas=2

In the above example, the file contains three sections, each containing different Kafka configuration properties. The first section specifies general Kafka configurations such as the broker ID, the number of network and I/O threads, and the socket buffer sizes. The second section specifies Zookeeper configurations such as the connection string and the connection timeout. The last section specifies topic configurations such as the number of partitions, the default replication factor, and the minimum number of in-sync replicas.

To use a Kafka property file, you need to pass it to the Kafka command line tools or to the Kafka broker as a JVM property. For example, to pass a Kafka property file to the Kafka command line tools, you can use the following command

kafka-topics.sh --zookeeper localhost:2181 --create --topic my-topic --config my-config-file.properties

kafka + springboot + mysql properties file 

To configure a Spring Boot application that uses Kafka and MySQL, you need to create a properties file that specifies the relevant configuration properties. Here's an example of a properties file that can be used for such an application:

spring.kafka.bootstrap-servers=localhost:9092

spring.kafka.consumer.group-id=my-group

spring.kafka.producer.value-serializer=org.apache.kafka.common.serialization.StringSerializer

spring.kafka.consumer.value-deserializer=org.apache.kafka.common.serialization.StringDeserializer

spring.kafka.consumer.auto-offset-reset=earliest

spring.kafka.consumer.enable-auto-commit=false

spring.kafka.listener.poll-timeout=3000

spring.datasource.url=jdbc:mysql://localhost:3306/my-database

spring.datasource.username=my-username

spring.datasource.password=my-password

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

spring.jpa.hibernate.ddl-auto=create

spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect

In the above example, the properties related to Kafka include the bootstrap server URL, the consumer group ID, and the serializers/deserializers for the producer and consumer. The auto-offset-reset property specifies what to do if the consumer is reading a partition for the first time, and the enable-auto-commit property is set to false to manually commit offsets.

The properties related to MySQL include the database URL, username, and password. The driver-class-name property specifies the JDBC driver to use, and the ddl-auto property is set to create to create the database schema automatically. Finally, the hibernate.dialect property specifies the dialect to use with Hibernate.

To use this properties file in your Spring Boot application, you can place it in the src/main/resources directory and refer to it in your application.properties file using the spring.config.name and spring.config.location properties:

spring.config.name=my-application

spring.config.location=classpath:/,file:./config/

In the above example, the properties file is named my-application.properties and is located in either the classpath root or the ./config/ directory relative to the current working directory.