Large file must be uploaded with multi-phase upload API. Multi-phase API consists of 2 phases. Phase 1 is to initialize a upload session. Phase 2 is to upload the file content.
Multi-phase API is based on existing file upload APIs. When special headers are present with the old API request, server will handle it as multi-phase upload requests.
The request is the same as old API except that request body should be content of file only. Multi-part/form request is not allowed. The request can carry url parameters or custom headers which will override the value set in phase 1 request. However, it is not recommended as meta-data conflict can cause file uploading to fail.