Question

我的blob存储在blobstore中，并希望将这些文件推送到Google云端硬盘。当我使用Google App Engine UrlFetchService

时

URLFetchService fetcher = URLFetchServiceFactory.getURLFetchService();
URL url = new URL("https://www.googleapis.com/upload/drive/v1/files");
HTTPRequest httpRequest = new HTTPRequest(url, HTTPMethod.POST);
httpRequest.addHeader(new HTTPHeader("Content-Type", contentType));
httpRequest.addHeader(new HTTPHeader("Authorization", "OAuth " + accessToken));
httpRequest.setPayload(buffer.array());
Future<HTTPResponse> future = fetcher.fetchAsync(httpRequest);
try {
  HTTPResponse response = (HTTPResponse) future.get();
} catch (Exception e) {
  log.warning(e.getMessage());
}

问题：当文件超过5 mb时，它超出了UrlFetchService请求大小的限制（链接：https://developers.google.com/appengine/docs/java/urlfetch/overview#Quotas_and_Limits）

替代方案：使用Google Drive API，我有以下代码：

File body = new File();
body.setTitle(title);
body.setDescription(description);
body.setMimeType(mimeType);

// File's content.
java.io.File fileContent = new java.io.File(filename);
FileContent mediaContent = new FileContent(mimeType, fileContent);

File file = service.files().insert(body, mediaContent).execute();

此解决方案存在问题： Google App Engine不支持FileOutputStream来管理从Blobstore读取的byte []。

有什么想法吗？

Answer 1

要执行此操作，请使用小于5兆字节块的可恢复上载。这在Google API Java Client for Drive中很容易实现。以下是根据您提供的云端代码改编的代码示例。

File body = new File();
body.setTitle(title);
body.setDescription(description);
body.setMimeType(mimeType);

java.io.File fileContent = new java.io.File(filename);
FileContent mediaContent = new FileContent(mimeType, fileContent);

Drive.Files.Insert insert = drive.files().insert(body, mediaContent);
insert.getMediaHttpUploader().setChunkSize(1024 * 1024);
File file = insert.execute();

有关更多信息，请参阅相关类的javadoc：

如何将大型文件（> 5 MB）从Blobstore发布到Google云端硬盘？

1 个答案: