How do you use Spring Data MongoDB and other NoSQL stores in Spring Boot 4?

// MongoDB entity:
import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;

@Document(collection = "products")  // MongoDB collection name
public record Product(
    @Id String id,            // MongoDB ObjectId
    String name,
    BigDecimal price,
    String category,
    Instant createdAt
) {}

// MongoDB repository:
public interface ProductRepository
        extends MongoRepository<Product, String> {

    List<Product> findByCategory(String category);
    List<Product> findByPriceLessThan(BigDecimal maxPrice);

    // MongoDB query annotation:
    @Query("{ \"category\": ?0, \"price\": { \"$lt\": ?1 } }")
    List<Product> findByCategoryAndMaxPrice(String category, BigDecimal maxPrice);
}

# application.yml: MongoDB connection:
spring:
  data:
    mongodb:
      uri: mongodb://localhost:27017/products-db
      # or:
      host: localhost
      port: 27017
      database: products-db
      username: ${MONGO_USER}
      password: ${MONGO_PASS}

# application.yml: Redis connection:
spring:
  data:
    redis:
      host: localhost
      port: 6379
      password: ${REDIS_PASS}
      timeout: 2s

// Redis template usage:
@Service
public class SessionService {
    private final RedisTemplate<String, Object> redisTemplate;
    public void store(String key, Object value, Duration ttl) {
        redisTemplate.opsForValue().set(key, value, ttl);
    }
}