You can use ECS extensions to the EMC Atmos protocol to append data to an object.
There may be cases where you need to append to an object, but determining the exact byte offset is not efficient or useful. For this scenario, ECS provides the ability to atomically append data to the object without specifying an offset (the correct offset is returned to you in the response).
A Range header with the special value bytes=-1- is used to append data to an object. In this way, the object can be extended without knowing the existing object size. The format is:
Range: bytes=-1-
A sample request showing appending to an existing object using a Range value of
bytes=-1- is shown in the following example. Here the value
and cat is sent in the request.