Create file download URL

Creates a presigned download URL and returns file metadata for client-side HTTP download.

Create file download URL creates a short-lived download URL for a file in the current application. The file bytes are downloaded by client over HTTP using the returned presigned_url.

Request

Create file download URL uses packet type = 7.

{
  "type": 7,
  "id": 8,
  "filename": "client.dll",
  "resume_at": 0
}

Prop

Type

Response

{
  "id": 8,
  "presigned_url": "https://cdn.example.net/...",
  "file_size": 1832456,
  "file_checksum": "2f57f0f6f4f8f7df8f4f395f6efc58f3e0681c6cf8f8a53fd2f1f4d76ab4bc9e",
  "status": 1
}

Prop

Type

Client download flow

Send websocket Create file download URL packet and wait for status.

If status = Ok, send HTTP GET request to presigned_url.

If resume_at > 0, include HTTP header Range: bytes=<resume_at>-.

Validate downloaded bytes against checksum policy in your client library.

Checksum notes

file_checksum always represents the full stored file.
If download starts from byte 0, client can compare full-file checksum directly.
If resumed (resume_at > 0), checksum validation strategy depends on your client implementation.
FileChecksumMismatch belongs to client-side download validation and is not returned by this websocket packet.