Introduction

A file session object is a named binary or text file: an envelope holding metadata, with the bytes stored separately. It can only be created by upload_session_file — upload_session_object refuses a value.type of "file".

Envelope

upload_session_file writes the bytes and the envelope together in one call. The stored value looks like:

{
  "type": "file",
  "file": {
    "name": "report.pdf",
    "content_type": "application/pdf",
    "size": 154829,
    "sha256": "bc3863f758932818eedbdaa783c4f7b62e5119c87cbd94725e2ce483c5623fe7"
  }
}

Field	Type	Description
`name`	string	File name, 1–256 characters.
`content_type`	string	Normalized MIME type (parameters dropped, lower-cased).
`size`	integer	Size of the stored bytes.
`sha256`	string	SHA-256 digest of the stored bytes, as lowercase hex.

The bytes themselves live at a side storage prefix next to the object store, not inside it — they are never listed as a second object by List Session Objects, and only download_session_file reads them back. Deleting the object with delete_session_object cascades and removes the bytes with it; deleting the session purges every file’s bytes along with everything else in it.

Limits

Limit	Value
Max file size	4 MiB per file.
Allowed content types	`image/png`, `image/jpeg`, `image/gif`, `image/webp`, `application/pdf`, `application/json`, `text/`, `audio/`, `video/`, `application/vnd.openxmlformats-officedocument.` — a trailing `*` matches its whole family by prefix.

upload_session_object refuses a value.type of "file" — a file object can only be created with upload_session_file, so a file envelope never exists without bytes behind it.

Operations

Operation	Description
Upload Session File	Upload bytes, creating or replacing the file object.
Download Session File	Download the bytes and the envelope together.

Overview

Workflow

Scheduler

ONNX

Envelope

Limits

Operations

See also

​Envelope

​Limits

​Operations

​See also

Envelope

Limits

Operations

See also