Allow Jedis to be selected when both Jedis and Lettuce are on the classpath

[brucelwl]

If both Lettuce and Jedis exist on the classpath, LettuceConnectionConfiguration and JedisConnectionConfiguration will be created, but actually JedisConnectionConfiguration is not necessary. It is recommended to add redis client type configuration, for example：
spring.redis.client.type=jedis，
spring.redis.client.type=lettuce

@Configuration(proxyBeanMethods = false)
@ConditionalOnClass({ GenericObjectPool.class, JedisConnection.class, Jedis.class })
@ConditionalOnProperty(name = "spring.redis.client.type", havingValue = "jedis", matchIfMissing = true)
class JedisConnectionConfiguration extends RedisConnectionConfiguration {
      //...
}

@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(RedisClient.class)
@ConditionalOnProperty(name = "spring.redis.client.type", havingValue = "lettuce", matchIfMissing = true)
class LettuceConnectionConfiguration extends RedisConnectionConfiguration {
     //...
}

[wilkinsona]

If both Lettuce and Jedis are on the classpath, Lettuce should win. LettuceConnectionConfiguration will define its redisConnectionFactory bean and the equivalent bean in JedisConnectionConfiguration should then back off as it is @ConditionalOnMissingBean(RedisConnectionFactory.class).

If you have both Lettuce and Jedis on the classpath, there's no easy way to use Jedis and a property could help with that (and would align with what we've done for JDBC datasources). I'm not sure what you mean by "JedisConnectionConfiguration is invalid" though. Could you expand on that a bit please?

[brucelwl]

@wilkinsona

1. If both Lettuce and Jedis are on the classpath, Lettuce should win. But now it seems that i can't specify the reids client type
2. if Lettuce win,JedisConnectionConfiguration is not necessary to register in the spring container

[wilkinsona]

if Lettuce win,JedisConnectionConfiguration is not necessary to register in the spring container

This could be addressed by moving the @ConditionalOnMissingBean(RedisConnectionFactory.class) from the @Bean method to the class.

If both Lettuce and Jedis are on the classpath, Lettuce should win. But now it seems that i can't specify the reids client type

Thanks. I understand what you're suggesting now.

[onobc]

@wilkinsona I was going to head out on this unless you plan on doing so.

My intention is to add the client type property and use that to choose the connection factory as suggested above. That also brings up a question for RedisProperties. There is a clientName property currently. Should we add another clientType or go ahead and split into its own property object -> client.name client.type. ?

[snicoll]

I am having second though about this one. As far as I remember, Jedis in in maintenance mode and Lettuce is the recommended choice. There are a number of things the user could do for this particular problem:

• If Jedis is brought by a dependency, they can fine tune their build to exclude the unwanted dependency
• They can exclude the Lettuce auto-configuration

I know we've considered dropping support for Jedis at some point. If that's still the target, I don't think exposing a property for it makes sense.

Paging @mp911de for more feedback.