优化：PDF文件下载缓存

jodconverter-web/src/main/java/cn/keking/service/impl/PdfFilePreviewImpl.java

@@ -26,6 +26,8 @@ public class PdfFilePreviewImpl implements FilePreview {
 
     private final DownloadUtils downloadUtils;
 
+    private static final String FILE_DIR = ConfigConstants.getFileDir();
+
     public PdfFilePreviewImpl(FileUtils fileUtils,
                               PdfUtils pdfUtils,
                               DownloadUtils downloadUtils) {
@@ -41,16 +43,22 @@ public class PdfFilePreviewImpl implements FilePreview {
         String officePreviewType = model.asMap().get("officePreviewType") == null ? ConfigConstants.getOfficePreviewType() : model.asMap().get("officePreviewType").toString();
         String baseUrl = BaseUrlFilter.getBaseUrl();
         String pdfName = fileName.substring(0, fileName.lastIndexOf(".") + 1) + "pdf";
-        String outFilePath;
+        String outFilePath = FILE_DIR + pdfName;
         if (OfficeFilePreviewImpl.OFFICE_PREVIEW_TYPE_IMAGE.equals(officePreviewType) || OfficeFilePreviewImpl.OFFICE_PREVIEW_TYPE_ALL_IMAGES.equals(officePreviewType)) {
             //当文件不存在时，就去下载
-            ReturnResponse<String> response = downloadUtils.downLoad(fileAttribute, fileName);
-            if (0 != response.getCode()) {
-                model.addAttribute("fileType", suffix);
-                model.addAttribute("msg", response.getMsg());
-                return "fileNotSupported";
+            if (!fileUtils.listConvertedFiles().containsKey(pdfName) || !ConfigConstants.isCacheEnabled()) {
+                ReturnResponse<String> response = downloadUtils.downLoad(fileAttribute, fileName);
+                if (0 != response.getCode()) {
+                    model.addAttribute("fileType", suffix);
+                    model.addAttribute("msg", response.getMsg());
+                    return "fileNotSupported";
+                }
+                outFilePath = response.getContent();
+                if (ConfigConstants.isCacheEnabled()) {
+                    // 加入缓存
+                    fileUtils.addConvertedFile(pdfName, fileUtils.getRelativePath(outFilePath));
+                }
             }
-            outFilePath = response.getContent();
             List<String> imageUrls = pdfUtils.pdf2jpg(outFilePath, pdfName, baseUrl);
             if (imageUrls == null || imageUrls.size() < 1) {
                 model.addAttribute("msg", "pdf转图片异常，请联系管理员");
@@ -67,13 +75,20 @@ public class PdfFilePreviewImpl implements FilePreview {
         } else {
             // 不是http开头，浏览器不能直接访问，需下载到本地
             if (url != null && !url.toLowerCase().startsWith("http")) {
-                ReturnResponse<String> response = downloadUtils.downLoad(fileAttribute, pdfName);
-                if (0 != response.getCode()) {
-                    model.addAttribute("fileType", suffix);
-                    model.addAttribute("msg", response.getMsg());
-                    return "fileNotSupported";
-                } else {
+                if (!fileUtils.listConvertedFiles().containsKey(pdfName) || !ConfigConstants.isCacheEnabled()) {
+                    ReturnResponse<String> response = downloadUtils.downLoad(fileAttribute, pdfName);
+                    if (0 != response.getCode()) {
+                        model.addAttribute("fileType", suffix);
+                        model.addAttribute("msg", response.getMsg());
+                        return "fileNotSupported";
+                    }
                     model.addAttribute("pdfUrl", fileUtils.getRelativePath(response.getContent()));
+                    if (ConfigConstants.isCacheEnabled()) {
+                        // 加入缓存
+                        fileUtils.addConvertedFile(pdfName, fileUtils.getRelativePath(outFilePath));
+                    }
+                } else {
+                    model.addAttribute("pdfUrl", pdfName);
                 }
             } else {
                 model.addAttribute("pdfUrl", url);

jodconverter-web/src/main/resources/web/index.ftl

@@ -195,7 +195,7 @@ window.open('http://127.0.0.1:8012/picturesPreview?urls='+encodeURIComponent(fil
         }).on('pre-body.bs.table', function (e,data) {
             // 每个data添加一列用来操作
             $(data).each(function (index, item) {
-                item.action = "<a class='btn btn-default' target='_blank' href='${baseUrl}onlinePreview?url="+ encodeURIComponent('${baseUrl}' + encodeURI(item.fileName)) +"'>预览</a>" +
+                item.action = "<a class='btn btn-default' target='_blank' href='${baseUrl}onlinePreview?url="+ encodeURIComponent('${baseUrl}' + item.fileName) +"'>预览</a>" +
                     "<a class='btn btn-default' href='javascript:void(0);' onclick='deleteFile(\""+item.fileName+"\")'>删除</a>";
             });
             return data;