anchor.diff:  
   validate_onbill(Context,?CARRIERS, Id, AttachmentId, ?HTTP_GET) ->
       load_carrier_attachment(Context, build_carrier_doc_id(Id, Context), <<Id/binary, "_", AttachmentId/binary, ".tpl">>);
  +validate_onbill(Context,?CARRIERS, Id, AttachmentId, ?HTTP_POST) ->
  +    save_carrier_attachment(Context, build_carrier_doc_id(Id, Context), <<Id/binary, "_", AttachmentId/binary, ".tpl">>);
   validate_onbill(Context,?MODB, Id, ?ATTACHMENT, ?HTTP_GET) ->
       load_modb_attachment(Context, Id).
   
  
positive.code: content_types_provided(Context,?MODB,_,?ATTACHMENT) ->
      CTP = [{'to_binary', [{<<"application">>, <<"pdf">>}]}],
      cb_context:set_content_types_provided(Context, CTP).
  
  -spec validate(cb_context:context()) -> cb_context:context().
  -spec validate(cb_context:context(), path_token()) -> cb_context:context().
  
negative.code:          ,allowed_methods/0, allowed_methods/1, allowed_methods/2, allowed_methods/3
           ,resource_exists/0, resource_exists/1, resource_exists/2, resource_exists/3
           ,content_types_provided/1, content_types_provided/3, content_types_provided/4
           ,content_types_accepted/4
           ,validate/1, validate/2, validate/3, validate/4
          ]).
  
  