java - 我如何使用GAE上传谷歌云存储中的文件

Question

在GAE中上传文件时，我可以使用如下代码，

 //here creating a blob store service
    BlobstoreService blobstoreService = BlobstoreServiceFactory.getBlobstoreService();
//here declaring the datastore service
   DatastoreService datastore = DatastoreServiceFactory.getDatastoreService();
//creating entity
   Entity emp = new Entity("Employee");
//set the property
   emp.setProperty("First Name", fname);
   emp.setProperty("Last Name", lname);
//storing the data in GAE
   datastore.put(Employee);

现在，如果我需要在 Google 云存储中执行相同的文件上传操作，我可以设置存储桶并打开 channel ，如下所示，

//Creating file service
FileService fileService = FileServiceFactory.getFileService();

//setting bucket name,object name & type
GSFileOptionsBuilder optionsBuilder = new GSFileOptionsBuilder()
       .setBucket(BUCKETNAME)
       .setKey(FILENAME)
       .setMimeType("text/html")
       .setAcl("public_read")
       .addUserMetadata("myfield1", "my field value");

//creating the new writable file 
 AppEngineFile writableFile =fileService.createNewGSFile(optionsBuilder.build());
//opening the lock and writing channel
boolean lock = false;
FileWriteChannel writeChannel = fileService.openWriteChannel(writableFile, lock);

此后我不知道如何将文件存储在 Google 云存储中。我引用了这个开发者页面Google Cloud Storage Java API Overview但它仅显示对对象的读取和写入而不上传文件。

请向我提出一个将文件上传到 Google 云存储的想法。

感谢您的帮助。

Answer 1

类似这样的事情:

UploadOptions uploadOptions = UploadOptions.Builder.withGoogleStorageBucketName("bucket");
String uploadUrl = blobstoreService.createUploadUrl("/on_upload_success", uploadOptions));

然后 POST 到该 url。但是，然后在 '/on_upload_success' 处理程序中，您将从 GS 获取文件的 BlobKey，而不是文件名(由于此错误 http://code.google.com/p/googleappengine/issues/detail?id=8337 )。因此，您只能使用 blobkey 从 GAE 读取该数据。