title: Using Blobstore from JUnit
body: <p>I am trying to test some code that uses the Blobstore API, but I don't really get how I am expected to get some files into the blobstore. The following is not working:</p>
  
  <pre><code>private BlobKey createBlob(String path) throws Exception {
      FileService fileService = FileServiceFactory.getFileService();
      AppEngineFile file = fileService.createNewBlobFile("foobar");
      FileWriteChannel writeChannel = fileService.openWriteChannel(file, true);
      OutputStream output = Channels.newOutputStream(writeChannel);
  
      // copy files, guava-style
      InputStream input = new FileInputStream(path);
      assertNotNull(input);
      ByteStreams.copy(input, output); 
      input.close();
  
      // just in case...
      output.flush();
      output.close();
      writeChannel.close();
  
      // U NO WORK!!!
      BlobKey blobKey = fileService.getBlobKey(file);
      assertNotNull(blobKey);
      return blobKey;
  }
  </code></pre>
  
  <p>My config:</p>
  
  <pre><code>new LocalServiceTestHelper(
      new LocalBlobstoreServiceTestConfig()
          //.setNoStorage(true)
          .setBackingStoreLocation("war/WEB-INF/appengine-generated"),
      new LocalFileServiceTestConfig()
  ).setUp();
  </code></pre>
  
  <p>Any ideas?</p>