CreateUploadHandler

# CreateUploadHandler API

Creates a server-side temporary upload handler that enables large file uploads to be sent in smaller chunks. Returns a handler GUID and the negotiated chunk size to use for subsequent UploadFileChunk calls.

This is the first step in the chunked upload workflow. The handler acts as a staging area on the server until the upload is finalized by UploadDocumentWithHandler.

Endpoint¶

/srv.asmx/CreateUploadHandler

Methods¶

GET /srv.asmx/CreateUploadHandler?authenticationTicket=...&PreferedChunkSize=...
POST /srv.asmx/CreateUploadHandler (form data)
SOAP Action: http://tempuri.org/CreateUploadHandler

Parameters¶

Parameter	Type	Required	Description
`authenticationTicket`	string	Yes	Authentication ticket obtained from `AuthenticateUser`.
`PreferedChunkSize`	int	Yes	Preferred chunk size in bytes for subsequent `UploadFileChunk` calls. Pass `0` to use the system default. The server enforces a minimum of 262,144 bytes (256 KB) and a maximum of 33,554,432 bytes (32 MB); values outside this range are silently clamped to the nearest limit.

Response¶

Success Response¶

<response success="true" error="" UploadHandler="a1b2c3d4-e5f6-7890-abcd-ef1234567890" ChunkSize="1048576" />

Attribute	Description
`success`	`true` if the handler was created successfully.
`UploadHandler`	GUID string identifying the upload handler. Pass this value to every subsequent `UploadFileChunk` and `UploadDocumentWithHandler` call.
`ChunkSize`	The actual chunk size in bytes the server has accepted (after clamping). Split the file into chunks of exactly this size (the last chunk may be smaller) when calling `UploadFileChunk`.

Error Response¶

<response success="false" error="Error message" />

Required Permissions¶

Any authenticated user may call this API.

Chunked Upload Workflow¶

Use the following sequence to upload a large file in chunks:

CreateUploadHandler -" Allocate a handler and obtain the UploadHandler GUID and ChunkSize.
UploadFileChunk -" Send the file in sequential chunks of ChunkSize bytes, passing LastChunk=true on the final chunk.
UploadDocumentWithHandler (or UploadDocumentWithHandler1 / UploadNewDocumentWidthHandler) -" Finalize the upload: move the staged file into the document library and create the document or new version.
DeleteUploadHandler -" Clean up the handler if the upload is cancelled or if an error occurs before step 3 completes.

Example¶

GET Request¶

GET /srv.asmx/CreateUploadHandler

  ?authenticationTicket=3f2504e0-4f89-11d3-9a0c-0305e82c3301

  &PreferedChunkSize=1048576

HTTP/1.1

POST Request¶

POST /srv.asmx/CreateUploadHandler HTTP/1.1

Content-Type: application/x-www-form-urlencoded



authenticationTicket=3f2504e0-4f89-11d3-9a0c-0305e82c3301

&PreferedChunkSize=1048576

SOAP Request¶

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"

               xmlns:tns="http://tempuri.org/">

  <soap:Body>

    <tns:CreateUploadHandler>

      <tns:authenticationTicket>3f2504e0-4f89-11d3-9a0c-0305e82c3301</tns:authenticationTicket>

      <tns:PreferedChunkSize>1048576</tns:PreferedChunkSize>

    </tns:CreateUploadHandler>

  </soap:Body>

</soap:Envelope>

Notes¶

Pass PreferedChunkSize=0 to let the server select the default chunk size configured in the application settings.
The server silently clamps the chunk size: values below 256 KB (262,144 bytes) are raised to 256 KB; values above 32 MB (33,554,432 bytes) are reduced to 32 MB.
Always use the ChunkSize value returned in the response -" not the value you requested -" when splitting the file into chunks for UploadFileChunk.
The handler exists only for the duration of the upload session. If the upload is not completed, call DeleteUploadHandler to free the temporary storage.
Upload handlers are tied to the authenticated user's session. A handler created with one ticket cannot be used with a different user's ticket.

UploadFileChunk - Upload a single chunk of a file to an open handler
UploadDocumentWithHandler - Finalize the upload and create or update a document
DeleteUploadHandler - Delete an upload handler and discard its staged data
UploadDocument - Upload a complete document in a single call (no handler required)

Error Codes¶

Error	Description
`[900] Authentication failed`	Invalid or missing authentication ticket.
`[901] Session expired or Invalid ticket`	The ticket has expired or does not exist.