Final Project: Achieve a AccountManagementSystem and MasterCardApp, we can register a new account, then the system will generate a new id and a new unique token at the same time, when MasterCardApp send a token to AccountManagementSystem, it will validate the token in the DB and send the status back to the MasterCardApp.

• Add MySQL dependency first.
• Configure the application.properties like the following.

spring.datasource.url=jdbc:mysql://{Hostname}:{port}/{database}
spring.datasource.username={username}
spring.datasource.password={password}

Link: https://www.conduktor.io/kafka/how-to-install-apache-kafka-on-mac

echo 'export PATH="$PATH:/Users/xiao/kafka_2.13-3.3.2/bin"' >> ~/.zshenv
source ~/.zshenv

// test
echo $PATH
kafka-topics.sh

From the root of Apache Kafka, run the following command to start Zookeeper:

~/kafka_2.13-3.3.2/bin/zookeeper-server-start.sh ~/kafka_2.13-3.3.2/config/zookeeper.properties

Open another Terminal window and run the following command from the root of Apache Kafka to start Apache Kafka.

~/kafka_2.13-3.3.2/bin/kafka-server-start.sh ~/kafka_2.13-3.3.2/config/server.properties

• producer: generate token and send it to AccountManagementSystem
• consumer: get validated result

• producer: receive token, store in Post_Status DB
• consumer: get status from Post_Status DB, send to MasterCardApp

1. Error while fetching metadata with correlation id 1 : {topic=LEADER_NOT_AVAILABLE} Solution: https://blog.csdn.net/csdn_xpw/article/details/105179901