See: RedisPingIntegrationTest.java (no real tests yet, but this file works). The key fix is @DataRedisTest which specifies this Test will only load Redis-related imports while @ContextConfiguration lets me configure so that my RedisTestConfig.java file is used as my loading source of truth. For now, it's an isolated Testcontainers file that defines the containers inside the class, but I should similarly modularize it like I did with BaseContainerFile (or whatever it's called).

Author: timan-z

springqpro-backend/src/main/java/com/springqprobackend/springqpro/config/RedisConfig.java

@@ -1,4 +1,4 @@
-/*package com.springqprobackend.springqpro.config;
+package com.springqprobackend.springqpro.config;
 
 import com.fasterxml.jackson.annotation.JsonAutoDetect;
 import com.fasterxml.jackson.annotation.PropertyAccessor;
@@ -42,4 +42,3 @@ public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory conn
         return template;
     }
 }
-*/

springqpro-backend/src/main/java/com/springqprobackend/springqpro/redis/RedisDistributedLock.java

@@ -13,7 +13,7 @@
 - How to use: String token = lock.tryLock("task:lock:"+id, 10000); if(token!=null){ try { ... } finally { lock.unlock(...); } }
 SO BASICALLY, safe lock happens using SET NX PX, and we use a Lua script to unlock it. That's how this is going to work.
 */
-/*@Component
+@Component
 public class RedisDistributedLock {
     // Field(s):
     private final RedisTemplate<String, Object> redis;
@@ -42,4 +42,3 @@ public boolean unlock(String key, String token) {
         return res != null && res > 0;
     }
 }
-*/

springqpro-backend/src/main/java/com/springqprobackend/springqpro/redis/TaskRedisRepository.java

@@ -14,7 +14,7 @@
 - This file is a thin cache abstraction.
 - We'll be caching TaskEntity (DB representation, not domain Task). This is good DDD (Domain-Driven Design): Cache the authoritative persisted shape.
 */
-/*@Component
+@Component
 public class TaskRedisRepository {
     // Field(s):
     private static final String TASK_KEY_PREFIX = "task:";
@@ -43,4 +43,3 @@ public void delete(String id) {
     }
     // DEBUG:+NOTE:+TO-DO: I can add other methods like exists(), setIfAbsent() and so on...
 }
-*/

springqpro-backend/src/test/java/com/springqprobackend/springqpro/integration/RedisPingIntegrationTest.java

@@ -1,49 +1,46 @@
-/*package com.springqprobackend.springqpro.integration;
+package com.springqprobackend.springqpro.integration;
 
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.data.redis.DataRedisTest;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.TestConfiguration;
 import org.springframework.context.annotation.Import;
 import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.data.redis.core.StringRedisTemplate;
 import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.ContextConfiguration;
 import org.testcontainers.containers.GenericContainer;
 import org.testcontainers.junit.jupiter.Container;
 import org.testcontainers.junit.jupiter.Testcontainers;
 
 import com.springqprobackend.springqpro.config.RedisConfig;
+import org.testcontainers.utility.DockerImageName;
 
-@SpringBootTest(classes = { RedisConfig.class })
-@ActiveProfiles("test")
+@DataRedisTest
 @Testcontainers
-public class RedisPingIntegrationTest {
-
-    @Container
-    static GenericContainer<?> redis =
-            new GenericContainer<>("redis:7.2")
-                    .withExposedPorts(6379);
+@ContextConfiguration(classes = { RedisPingIntegrationTest.Config.class })
+class RedisPingIntegrationTest {
+
+    @TestConfiguration
+    @Import(com.springqprobackend.springqpro.config.RedisConfig.class)
+    static class Config {
+        static GenericContainer<?> REDIS =
+                new GenericContainer<>(DockerImageName.parse("redis:7.2"))
+                        .withExposedPorts(6379);
+        static {
+            REDIS.start();
+            System.setProperty("spring.data.redis.host", REDIS.getHost());
+            System.setProperty("spring.data.redis.port", REDIS.getMappedPort(6379).toString());
+        }
+    }
 
     @Autowired
-    RedisTemplate<String, Object> redisTemplate;
-
-    @BeforeAll
-    static void setup() {
-        System.setProperty("spring.redis.host", redis.getHost());
-        System.setProperty("spring.redis.port",
-                redis.getMappedPort(6379).toString());
-    }
+    private StringRedisTemplate stringRedisTemplate;
 
     @Test
-    void redisPingPong() {
-        String key = "ping";
-        String value = "pong";
-
-        redisTemplate.opsForValue().set(key, value);
-
-        String fetched = (String) redisTemplate.opsForValue().get(key);
-
-        assert fetched != null;
-        assert fetched.equals(value);
+    void testPing() {
+        System.out.println("What's poppin!");
     }
-}
-*/
+}

springqpro-backend/src/test/java/com/springqprobackend/springqpro/testcontainers/RedisIntegrationTestBase.java

@@ -1,4 +1,4 @@
-/*package com.springqprobackend.springqpro.testcontainers;
+package com.springqprobackend.springqpro.testcontainers;
 
 import com.springqprobackend.springqpro.config.RedisTestConfig;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
@@ -23,4 +23,4 @@ static void overrideRedisProps(DynamicPropertyRegistry registry) {
         registry.add("spring.redis.host", REDIS::getHost);
         registry.add("spring.redis.port", () -> REDIS.getMappedPort(6379));
     }
-}*/
+}