pub const HEADER_SESSION: &'static str;Expand description
HTTP header carrying a per-upload session id.
When present, the upload uses the concurrent “session” protocol: each
chunk carries its ABSOLUTE x-libfw-offset and is written into a shared
per-session temp file (positional writes), and the final
x-libfw-final request commits it. This lets a client pipeline many
chunks in flight (hiding round-trip latency) instead of serializing one
request per chunk. Absent → legacy per-request sequential upload.
A session id should be stable for a given file version (derived from
the ETag) so an interrupted upload can be found again on resume: the
shared temp file is keyed by this id, and the server persists which byte
ranges have already been received (see HEADER_SESSION_STATUS).