code: @GET
      @Produces(MediaType.APPLICATION_JSON)
      public Response getBatches(@Context HttpServletRequest req) {
          PrincipalUser owner = validateAndGetOwner(req, null);
          SystemAssert.requireArgument(owner != null, "Owner cannot be null");
  
          Map<String,String> batches = batchService.findBatchesByOwnerName(owner.getUserName());
          return Response.ok(batches, MediaType.APPLICATION_JSON).build();
      }
docs: Returns all batches filtered by owner
  
  @param   req          HTTPServlet request. Cannot be null.
  
  @return  Filtered batches in the form of a map from UUID to status