Question

i am trying to store data from the app engine app to google cloud storage.

if i do it locally code runs fine but i dont see any data being stored.

if i upload the app to the app engine then i get a null pointer exception on running the code at:
AppEngineFile writableFile = fileService.createNewGSFile(optionsBuilder.build());

the complete code i m using is

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

        /**
         * Set up properties of your new object
         * After finalizing objects, they are accessible
         * through Cloud Storage with the URL:
         * http://commondatastorage.googleapis.com/my_bucket/my_object
         */
        GSFileOptionsBuilder optionsBuilder = new GSFileOptionsBuilder()
          .setBucket("blood")
          .setKey("1234567")
          .setAcl("public-read")
          .setMimeType("text/html");//.setUserMetadata("date-created", "092011", "owner", "Jon");


        // Create your object
        AppEngineFile writableFile = fileService.createNewGSFile(optionsBuilder.build());

        // Open a channel for writing
        boolean lockForWrite = true; // Do you want to exclusively lock this object?
        FileWriteChannel writeChannel = fileService.openWriteChannel(writableFile, lockForWrite);
        // For this example, we write to the object using the PrintWriter
        PrintWriter out = new PrintWriter(Channels.newWriter(writeChannel, "UTF8"));
        out.println("The woods are lovely and deep.");
        out.println("But I have promises too keep.");

        // Close the object without finalizing.
        out.close();

        // Finalize the object
        writeChannel.closeFinally();
        System.out.println("Completed writing to google storage");

Answer 1

So the problem was that app engine was not authorized to read/write to the bucket created in the cloud store.