langchain4j+redis+持久化存储记忆

langchain4jredis持久化存储记忆一、前言Langchain4j官方默认模型记忆用内存存储但是这样只要重启进程记忆就会消失。这里我们利用redis的持久化存储RDBAOF来解决这个问题这样的搭配高效且方便。二、环境和依赖Java 17(langchain4j最低支持)dependency groupIddev.langchain4j/groupId artifactIdlangchain4j/artifactId version1.3.0/version /dependency dependency groupIddev.langchain4j/groupId artifactIdlangchain4j-community-dashscope-spring-boot-starter/artifactId version1.1.0-beta7/version /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-data-redis/artifactId version3.1.5/version /dependency当然还需要本地redis环境。三、实战配置spring: data: redis: host: localhost port: 6379MemoryConfigConfiguration public class MemoryConfig { // redis Bean public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory factory) { return new StringRedisTemplate(factory); } Bean public RedisChatMemoryStore redisChatMemoryStore( StringRedisTemplate redisTemplate, ObjectMapper objectMapper) { return new RedisChatMemoryStore(redisTemplate, objectMapper); } }RedisConfigConfiguration public class RedisConfig { Bean public RedisTemplateString, Object redisTemplate(RedisConnectionFactory factory) { RedisTemplateString, Object template new RedisTemplate(); template.setConnectionFactory(factory); // key序列化 StringRedisSerializer stringSerializer new StringRedisSerializer(); // value序列化JSON 支持多态 GenericJackson2JsonRedisSerializer jsonSerializer new GenericJackson2JsonRedisSerializer(); // 设置序列化 template.setKeySerializer(stringSerializer); template.setHashKeySerializer(stringSerializer); template.setValueSerializer(jsonSerializer); template.setHashValueSerializer(jsonSerializer); template.afterPropertiesSet(); return template; } }ChatMessageDTOpackage cn.langchain4j.ai.dto; import lombok.Getter; Getter public class ChatMessageDTO { private String role; // user / ai / system private String content; public ChatMessageDTO() {} public ChatMessageDTO(String role, String content) { this.role role; this.content content; } public void setRole(String role) { this.role role; } public void setContent(String content) { this.content content; } }ChatMessageConverterpackage cn.langchain4j.ai.memory; import cn.langchain4j.ai.dto.ChatMessageDTO; import dev.langchain4j.data.message.*; public class ChatMessageConverter { // LangChain4j - DTO public static ChatMessageDTO toDTO(ChatMessage msg) { if (msg instanceof UserMessage m) { return new ChatMessageDTO(user, m.singleText()); } if (msg instanceof AiMessage m) { return new ChatMessageDTO(ai, m.text()); } if (msg instanceof SystemMessage m) { return new ChatMessageDTO(system, m.text()); } throw new IllegalArgumentException(Unknown message type: msg.getClass()); } // DTO - LangChain4j public static ChatMessage toDomain(ChatMessageDTO dto) { return switch (dto.getRole()) { case user - UserMessage.from(dto.getContent()); case ai - AiMessage.from(dto.getContent()); case system - SystemMessage.from(dto.getContent()); default - throw new IllegalArgumentException(Unknown role: dto.getRole()); }; } }RedisChatMemoryStorepackage cn.langchain4j.ai.memory; import cn.langchain4j.ai.dto.ChatMessageDTO; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.ObjectMapper; import dev.langchain4j.data.message.ChatMessage; import dev.langchain4j.store.memory.chat.ChatMemoryStore; import org.springframework.data.redis.core.StringRedisTemplate; import java.util.ArrayList; import java.util.List; public class RedisChatMemoryStore implements ChatMemoryStore { private final StringRedisTemplate redisTemplate; private final ObjectMapper objectMapper; public RedisChatMemoryStore(StringRedisTemplate redisTemplate, ObjectMapper objectMapper) { this.redisTemplate redisTemplate; this.objectMapper objectMapper; } private String buildKey(Object memoryId) { return chat_memory: memoryId; } Override public ListChatMessage getMessages(Object memoryId) { try { String json redisTemplate.opsForValue().get(buildKey(memoryId)); if (json null) { return new ArrayList(); } ListChatMessageDTO dtoList objectMapper.readValue(json, new TypeReferenceListChatMessageDTO() {}); return dtoList.stream() .map(ChatMessageConverter::toDomain) .toList(); } catch (Exception e) { throw new RuntimeException(e); } } Override public void updateMessages(Object memoryId, ListChatMessage messages) { try { ListChatMessageDTO dtoList messages.stream() .map(ChatMessageConverter::toDTO) .toList(); String json objectMapper.writeValueAsString(dtoList); redisTemplate.opsForValue().set(buildKey(memoryId), json); } catch (Exception e) { throw new RuntimeException(e); } } Override public void deleteMessages(Object memoryId) { redisTemplate.delete(buildKey(memoryId)); } }AiCodeHelperServiceFactoryConfiguration public class AiCodeHelperServiceFactory { Resource private ChatModel qwenChatModel; Resource private ContentRetriever contentRetriever; Resource private McpToolProvider mcpToolProvider; Resource private RedisChatMemoryStore redisChatMemoryStore; Resource private StreamingChatModel streamingChatModel; Bean public AiCodeHelperService aiCodeHelperService(){ // 会话记忆 // 构建 AiCodeHelperService aiCodeHelperService AiServices.builder(AiCodeHelperService.class) .streamingChatModel(streamingChatModel) .chatModel(qwenChatModel) .chatMemoryProvider(memoryId - MessageWindowChatMemory.builder() .id(memoryId) .maxMessages(10) .chatMemoryStore(redisChatMemoryStore) // Redis记忆 .build() ) // .contentRetriever(contentRetriever) // 内容检索 (启用 RAG) .tools(new JavaInfoTool(), new RagTool()) // 工具 .toolProvider(mcpToolProvider) // mcp .build(); return aiCodeHelperService; } }