code: @SuppressWarnings("unchecked")
      @Scope(DocScope.IO)
      public String write(final Object projection) throws IOException {
          return IOHelper.inputStreamToString(IOHelper.httpPost(url, projection.toString(), requestProperties));
      }
docs: Post the projected document to a HTTP URL. The response is provided as a raw string.
  
  @param projection
  @return response as String
  @throws IOException