add ip getter

src/main/java/com/mir4updater/backend/controller/IpController.java

@@ -0,0 +1,16 @@
+package com.mir4updater.backend.controller;
+
+import com.mir4updater.backend.utils.IpUtils;
+import jakarta.servlet.http.HttpServletRequest;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class IpController {
+
+    @GetMapping("/public-ip")
+    public String getPublicIp(HttpServletRequest request) {
+        String clientIp = IpUtils.getClientIpAddress(request);
+        return "Your public IP address is: " + clientIp;
+    }
+}

src/main/java/com/mir4updater/backend/utils/IpUtils.java

@@ -0,0 +1,44 @@
+package com.mir4updater.backend.utils;
+
+import jakarta.servlet.http.HttpServletRequest;
+
+public class IpUtils {
+        public static String getClientIpAddress(HttpServletRequest request) {
+            String[] headersToCheck = {
+                    "X-Forwarded-For",
+                    "Proxy-Client-IP",
+                    "WL-Proxy-Client-IP",
+                    "HTTP_CLIENT_IP",
+                    "HTTP_X_FORWARDED_FOR"
+            };
+
+            String ip = null;
+            for (String header : headersToCheck) {
+                ip = request.getHeader(header);
+                if (isValidIp(ip)) {
+                    break;
+                }
+            }
+
+            // 处理多IP情况
+            if (ip != null && ip.contains(",")) {
+                ip = ip.split(",")[0].trim();
+            }
+
+            // 回退到默认方法
+            if (!isValidIp(ip)) {
+                ip = request.getRemoteAddr();
+            }
+
+            // 处理IPv6本地地址
+            if ("0:0:0:0:0:0:0:1".equals(ip)) {
+                ip = "127.0.0.1";
+            }
+
+            return ip;
+        }
+
+        private static boolean isValidIp(String ip) {
+            return ip != null && !ip.isEmpty() && !"unknown".equalsIgnoreCase(ip);
+        }
+}