Redis connection is failed - spring

Question

I'd like to work with Redis for manipulating sessions.But I get failure when running the spring boot app.So I guess that this error is coming from maven dependencies especially version conflicts.
Here is my maven dependencies:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.session</groupId>
<artifactId>spring-session-data-redis</artifactId>
<version>1.7.0.RELEASE</version>
</dependency>
<dependency>
<groupId>io.lettuce</groupId>
<artifactId>lettuce-core</artifactId>
<version>5.0.0.RELEASE</version>
</dependency>
</dependencies>
Notice that I added two dependencies in above pom.xml which there artifactId are spring-session-data-redis and lettuce-core.These dependencies are respectively responsible for Redis connection and ensuring thread safety for session connections.
When I run the spring boot app, I get the belowed error:
APPLICATION FAILED TO START
Description:
An attempt was made to call the method org.springframework.data.redis.connection.RedisConnection.getConfig(Ljava/lang/String;)Ljava/util/List; but it does not exist. Its class, org.springframework.data.redis.connection.RedisConnection, is available from the following locations:
jar:file:/C:/Users/aoutir/.m2/repository/org/springframework/data/spring-data-redis/2.0.10.RELEASE/spring-data-redis-2.0.10.RELEASE.jar!/org/springframework/data/redis/connection/RedisConnection.class
It was loaded from the following location:
file:/C:/Users/aoutir/.m2/repository/org/springframework/data/spring-data-redis/2.0.10.RELEASE/spring-data-redis-2.0.10.RELEASE.jar
Action:
Correct the classpath of your application so that it contains a single, compatible version of org.springframework.data.redis.connection.RedisConnection
Please any help is very appreciated,thanks in advance for your reply.

Answer 1

I have spent a whole day to resolve the exactly same issue. And after a whole day R&D, I found the solution.
dependencies {
implementation('org.springframework.boot:spring-boot-starter-data-jpa')
implementation('org.springframework.boot:spring-boot-starter-data-rest')
implementation('org.springframework.boot:spring-boot-starter-web')
implementation('org.springframework.boot:spring-boot-starter-security')
implementation('org.springframework.boot:spring-boot-starter-data-redis')
implementation('org.springframework.session:spring-session-data-redis')
runtimeOnly('org.springframework.boot:spring-boot-devtools')
testImplementation('org.springframework.boot:spring-boot-starter-test')
runtimeOnly('org.flywaydb:flyway-core')
runtimeOnly('com.h2database:h2')
// runtimeOnly('mysql:mysql-connector-java')
}
Use 'spring-boot-starter-data-redis' and 'spring-session-data-redis'.
Remove lettuse dependency as it is included in spring-boot-starter-data-redis as dependency.
Here is your dependencies:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.session</groupId>
<artifactId>spring-session-data-redis</artifactId>
</dependency>

Answer 2

Simply delete the explicit version for spring-session-data-redis and go with the version from the spring boot parent pom.
If you want to change the version of spring-session-data-redis, you have to ensure that none of the transitive dependencies is managed by the parent pom. If I downgrade to version 1.3 (version 1.7 could not be found) I end up with the following version mismatch as revealed by mvn -X dependency:tree:
[ESC[1;36mDEBUGESC[m] org.springframework.session:spring-session-data-redis:jar:1.3.3.RELEASE:compile
[ESC[1;36mDEBUGESC[m] org.apache.commons:commons-pool2:jar:2.5.0:compile (version managed from 2.4.2)
[ESC[1;36mDEBUGESC[m] org.springframework.data:spring-data-redis:jar:2.0.10.RELEASE:compile (version managed from 1.7.10.RELEASE)

Answer 3

Please replace the dependency
<dependency>
<groupId>org.springframework.session</groupId>
<artifactId>spring-session-data-redis</artifactId>
<version>1.7.0.RELEASE</version>
</dependency>
with
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-redis</artifactId>
</dependency>
The version management is done automatically and the started will initialize the redis cache.