Spring Boot 3 Redis

What is Redis ?

Redis is an open-source, in-memory NoSQL key-value store primarily used for caching, session storage, and message brokering. It stores data in RAM, which enables extremely fast read and write operations compared to traditional disk-based databases

Here's a more detailed breakdown:

In-memory Data Store:

Redis stores data in memory, making it significantly faster than disk-based databases.

NoSQL Key-Value Store:

Redis is a NoSQL database, meaning it doesn't adhere to the traditional relational database model. It uses a key-value pair structure, where each key maps to a value.

Caching:

Redis is commonly used as a cache to speed up applications by storing frequently accessed data in memory.

Session Storage:

It can store user session data, providing a fast and efficient way to manage sessions in web applications.

Message Broker:

Redis can also act as a message broker, allowing different parts of an application to communicate with each other.

Data Types:

Redis supports various data types, including strings, lists, sets, streams, and hashes, allowing for a wide range of data storage and manipulation.

Open Source and Enterprise Versions:

Redis is available as an open-source project and also has a commercial version (Redis Enterprise) that offers additional features and supports.

Redis official

Let's go to create new project spring boot.

spring initializr

Clone repo

Configuration Redis in Spring Boot Application

package com.example.redislearn.settings;

import com.example.redislearn.product.dto.ProductDto;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;

import java.time.Duration;

@Configuration  // Marks this class as a Spring configuration class
public class RedisConfig {
    @Bean  // Defines a Spring bean for RedisCacheManager
    public RedisCacheManager redisCacheManager(RedisConnectionFactory redisConnectionFactory) {
        // Define cache configuration
        RedisCacheConfiguration cacheConfig = RedisCacheConfiguration.defaultCacheConfig()
                .entryTtl(Duration.ofMinutes(10)) // Set time-to-live (TTL) for cache entries to 10 minutes
                .disableCachingNullValues() // Prevent caching of null values
                .serializeValuesWith(RedisSerializationContext.SerializationPair
                        .fromSerializer(new Jackson2JsonRedisSerializer<>(ProductDto.class))); // Serialize values using Jackson JSON serializer

        // Create and return a RedisCacheManager with the specified configuration
        return RedisCacheManager.builder(redisConnectionFactory)
                .cacheDefaults(cacheConfig) // Apply default cache configuration
                .build();
    }
}

Services

package com.example.redislearn.product.services;

import com.example.redislearn.product.dto.ProductDto;
import com.example.redislearn.product.entity.Product;
import com.example.redislearn.product.repository.ProductRepository;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;

@Service
public class ProductService {

    private final ProductRepository productRepository;

    public ProductService(ProductRepository productRepository) {
        this.productRepository = productRepository;
    }

    @CachePut(value="PRODUCT_CACHE", key="#result.id")
    public ProductDto createProduct(ProductDto productDto) {
        var product = new Product();
        product.setName(productDto.name());
        product.setPrice(productDto.price());

        Product savedProduct = productRepository.save(product);
        return new ProductDto(savedProduct.getId(), savedProduct.getName(),
                savedProduct.getPrice());
    }


    @Cacheable(value="PRODUCT_CACHE", key="#productId")
    public ProductDto getProduct(Long productId) {
        Product product = productRepository.findById(productId)
                .orElseThrow(() -> new IllegalArgumentException("Cannot find product with id " + productId));
        return new ProductDto(product.getId(), product.getName(),
                product.getPrice());
    }

    @CachePut(value="PRODUCT_CACHE", key="#result.id")
    public ProductDto updateProduct(ProductDto productDto) {
        Long productId = productDto.id();
        Product product = productRepository.findById(productId)
                .orElseThrow(() -> new IllegalArgumentException("Cannot find product with id " + productId));

        product.setName(productDto.name());
        product.setPrice(productDto.price());

        Product updatedProduct = productRepository.save(product);
        return new ProductDto(updatedProduct.getId(), updatedProduct.getName(),
                updatedProduct.getPrice());
    }

    @CacheEvict(value="PRODUCT_CACHE", key="#productId")
    public void deleteProduct(Long productId) {
        productRepository.deleteById(productId);
    }
}