Merge remote-tracking branch 'origin/wyc' into wyc

# Conflicts:
#	src/main/java/com/zhentao/groups/MongoDB/pojo/Message.java
#	src/main/java/com/zhentao/information/entity/ChatMessage.java
#	src/main/java/com/zhentao/information/service/WebSocketService.java

src/main/java/com/zhentao/information/entity/ChatMessage.java

@@ -14,14 +14,22 @@ public class ChatMessage {
 
     @Id
     private String id;
+
     @Indexed
     private String fromUserId;
+
     @Indexed
     private String toUserId;
+
     private String content;
-    private String type;          // 新增: text/image/video/file
+
+    private String type;
+
     private Long timestamp;
+
     private Boolean isRead;
+
+    // 复合索引：用于查询两个用户之间的聊天记录
     @Indexed
     private String chatId;
     // 新增文件元数据

src/main/java/com/zhentao/information/handler/WebSocketHandler.java

@@ -124,6 +124,7 @@ public class WebSocketHandler extends SimpleChannelInboundHandler<TextWebSocketF
         chatMessage.setToUserId(message.getToUserId());
         chatMessage.setContent(message.getContent());
         chatMessage.setType(message.getType());
+        chatMessage.setImageurl(message.getImageurl());
         chatMessage.setTimestamp(System.currentTimeMillis());
         chatMessage.setIsRead(false);
         chatMessage.setChatId(chatId);