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Latest version

Create upload session for existing file

post
https://upload.box.com/api/2.0
/files/:file_id/upload_sessions

This endpoint is in the version 2024.0. No changes are required to continue using it. For more details, see Box API versioning.

Creates an upload session for an existing file.

Related Guides

Request

bearer [ACCESS_TOKEN]
application/json

Path Parameters

stringin pathrequired
12345

The unique identifier that represents a file.

The ID for any file can be determined by visiting a file in the web application and copying the ID from the URL. For example, for the URL https://*.app.box.com/files/123 the file_id is 123.

Request Body

stringin bodyoptional
"Project.mov"

The optional new name of new file.

integer (int64)in bodyrequired
104857600

The total number of bytes of the file to be uploaded.

Response

application/jsonUpload session

Returns a new upload session.

application/jsonClient error

Returns an error if the file already exists, or if the account has run out of disk space.

application/jsonClient error

An unexpected client error.

post
Create upload session for existing file
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Request Example

Learn more about Box SDK versioning strategy.


cURL
curl -i -X POST "https://upload.box.com/api/2.0/files/12345/upload_sessions" \
     -H "authorization: Bearer <ACCESS_TOKEN>" \
     -H "content-type: application/json" \
     -d '{
       "file_size": 104857600
     }'
Python v4
file_size = 26000000
upload_session = client.file('11111').create_upload_session(file_size)
print(f'Created upload session {upload_session.id} with chunk size of {upload_session.part_size} bytes')

Response Example

{
  "id": "F971964745A5CD0C001BBE4E58196BFD",
  "type": "upload_session",
  "num_parts_processed": 455,
  "part_size": 1024,
  "session_endpoints": {
    "abort": "https://{box-upload-server}/api/2.0/files/upload_sessions/F971964745A5CD0C001BBE4E58196BFD",
    "commit": "https://{box-upload-server}/api/2.0/files/upload_sessions/F971964745A5CD0C001BBE4E58196BFD/commit",
    "list_parts": "https://{box-upload-server}/api/2.0/files/upload_sessions/F971964745A5CD0C001BBE4E58196BFD/parts",
    "log_event": "https://{box-upload-server}/api/2.0/files/upload_sessions/F971964745A5CD0C001BBE4E58196BFD/log",
    "status": "https://{box-upload-server}/api/2.0/files/upload_sessions/F971964745A5CD0C001BBE4E58196BFD",
    "upload_part": "https://{box-upload-server}/api/2.0/files/upload_sessions/F971964745A5CD0C001BBE4E58196BFD"
  },
  "session_expires_at": "2012-12-12T10:53:43-08:00",
  "total_parts": 1000
}