From 6006e1d1b9442c00b85058053d76f22758092030 Mon Sep 17 00:00:00 2001
From: zwt13703 <zwt13703@gmail.com>
Date: Wed, 13 May 2026 20:00:04 +0800
Subject: [PATCH] =?UTF-8?q?feat:=20onlinePreview=20=E6=8E=A5=E5=8F=A3?=
 =?UTF-8?q?=E4=B8=AD=EF=BC=8CURL=20=E6=8C=87=E5=90=91=E7=9A=84=E5=85=AC?=
 =?UTF-8?q?=E7=BD=91=E6=96=87=E4=BB=B6=E8=BF=87=E5=A4=A7=E5=AF=BC=E8=87=B4?=
 =?UTF-8?q?=E4=B8=8B=E8=BD=BD=E7=BC=93=E6=85=A2=EF=BC=8C=E4=BD=86=E8=BF=99?=
 =?UTF-8?q?=E4=BA=9B=E6=96=87=E4=BB=B6=E5=AE=9E=E9=99=85=E5=B0=B1=E5=AD=98?=
 =?UTF-8?q?=E6=94=BE=E5=9C=A8=E5=BD=93=E5=89=8D=E6=9C=8D=E5=8A=A1=E5=99=A8?=
 =?UTF-8?q?=E7=9A=84=20/home/img=20=E7=9B=AE=E5=BD=95=E4=B8=8B=EF=BC=8C?=
 =?UTF-8?q?=E9=9C=80=E8=A6=81=E4=BC=98=E5=85=88=E4=BD=BF=E7=94=A8=E6=9C=AC?=
 =?UTF-8?q?=E5=9C=B0=E6=96=87=E4=BB=B6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../controller/OnlinePreviewController.java   | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/server/src/main/java/cn/keking/web/controller/OnlinePreviewController.java b/server/src/main/java/cn/keking/web/controller/OnlinePreviewController.java
index 666e322..2b79eb8 100644
--- a/server/src/main/java/cn/keking/web/controller/OnlinePreviewController.java
+++ b/server/src/main/java/cn/keking/web/controller/OnlinePreviewController.java
@@ -25,9 +25,12 @@ import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import org.springframework.web.client.HttpClientErrorException;
 
+import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
+import java.net.URLDecoder;
+import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.List;
 
@@ -49,6 +52,7 @@ public class OnlinePreviewController {
     private static final String URL_PARAM_FTP_PASSWORD = "ftp.password";
     private static final String URL_PARAM_FTP_CONTROL_ENCODING = "ftp.control.encoding";
     private static final String URL_PARAM_FTP_PORT = "ftp.control.port";
+    private static final String LOCAL_FILE_ROOT = "/home/img";
 
     private final FilePreviewFactory previewFactory;
     private final CacheService cacheService;
@@ -82,6 +86,8 @@ public class OnlinePreviewController {
             String errorMsg = String.format(BASE64_DECODE_ERROR_MSG, "url");
             return otherFilePreview.notSupportedFile(model, errorMsg);
         }
+        // 优先检查本地文件，本地存在则直接使用，避免从公网下载大文件
+        fileUrl = checkLocalFile(fileUrl);
         FileAttribute fileAttribute = fileHandlerService.getFileAttribute(fileUrl, req);
 
         highlightall= KkFileUtils.htmlEscape(highlightall);
@@ -287,4 +293,31 @@ public class OnlinePreviewController {
         cacheService.addQueueTask(fileUrls);
         return "success";
     }
+
+    /**
+     * 检查本地是否已有该文件，若有则返回本地文件路径，避免从公网重复下载
+     *
+     * @param fileUrl 解码后的文件URL
+     * @return 本地文件路径（如果存在），否则返回原始URL
+     */
+    private String checkLocalFile(String fileUrl) {
+        if (fileUrl == null || (!fileUrl.startsWith("http://") && !fileUrl.startsWith("https://"))) {
+            return fileUrl;
+        }
+        try {
+            URL url = new URL(fileUrl);
+            String path = url.getPath();
+            if (path != null && !path.isEmpty()) {
+                String decodedPath = URLDecoder.decode(path, StandardCharsets.UTF_8);
+                File localFile = new File(LOCAL_FILE_ROOT, decodedPath);
+                if (localFile.exists() && localFile.isFile()) {
+                    logger.info("本地文件存在，使用本地文件：{}", localFile.getAbsolutePath());
+                    return "file://" + localFile.getAbsolutePath();
+                }
+            }
+        } catch (Exception e) {
+            logger.warn("检查本地文件失败，url：{}", fileUrl, e);
+        }
+        return fileUrl;
+    }
 }
\ No newline at end of file