Configure Redis leader follower(master-slave) replication Permalink to "Configure Redis leader follower(master-slave) replication"

Tip submitted by @zhx828

In the latest JHipster generator, it provides a redis cluster setting for production deployment. But oftentimes, that might be overkill for small projects. This document provides a solution to configure Redis leader follower (master-slave) replication. For more information about Redis Replication, please see here.

The following changes are based on my own project set up. I assume you have modified your application properties to setup Redis password, so you can adjust your own accordingly.

Step 1 Permalink to "Step 1"

Add file RedisProperties.java: ``` public class RedisProperties { String type; String password; MasterSlaveRedisCache masterSlaveCache; SingleRedisCache singleCache;

public String getType() {
    return type;
}

public void setType(String type) {
    this.type = type;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public MasterSlaveRedisCache getMasterSlaveCache() {
    return masterSlaveCache;
}

public void setMasterSlaveCache(MasterSlaveRedisCache masterSlaveCache) {
    this.masterSlaveCache = masterSlaveCache;
}

public SingleRedisCache getSingleCache() {
    return singleCache;
}

public void setSingleCache(SingleRedisCache singleCache) {
    this.singleCache = singleCache;
} } ```

Step 2 Permalink to "Step 2"

Add RedisProperties to ApplicationProperties.java ``` public class ApplicationProperties { …

private RedisProperties redis;

public RedisProperties getRedis() {
    return redis;
}

public void setRedis(RedisProperties redis) {
    this.redis = redis;
}
... } ```

Step 3 Permalink to "Step 3"

Update the file CacheConfiguration.java, method jcacheConfiguration. These changes have to be combined with the current cluster setup.

if (applicationProperties.getRedis().getType().equals(RedisType.SINGLE.getType())) {
    config.useSingleServer()
        .setAddress(applicationProperties.getRedis().getSingleCache().getAddress())
        .setPassword(applicationProperties.getRedis().getPassword());
} else if (applicationProperties.getRedis().getType().equals(RedisType.MASTER_SLAVE.getType())) {
    config.useMasterSlaveServers()
        .setMasterAddress(applicationProperties.getRedis().getMasterSlaveCache().getMasterAddress())
        .addSlaveAddress(applicationProperties.getRedis().getMasterSlaveCache().getSlaveAddress())
        .setPassword(applicationProperties.getRedis().getPassword());
} else {
    throw new Exception("The redis type " + applicationProperties.getRedis().getType() + " is not supported. Only single and master-slave are supported.");
}

Step 4 Permalink to "Step 4"

Update application-dev.yml to use single server ``` application: profile: dev redis: type: ‘single’ password: ‘public-redis-password’ single-cache: address: ‘redis://localhost:6379’

## Step 5
Update `application-prod.yml` to use master-slave servers

application: profile: prod redis: type: ‘master-slave’ password: ‘public-redis-password’ master-slave-cache: master-address: ‘redis://redis-master:6379’ slave-address: ‘redis://redis-slave:6379’

```