Upload Attachments

This document contains details for the /api/v1/envelope/attachment endpoint, including headers, request body, response fields, and status codes.

Endpoint

Method	Endpoint
POST	/api/v1/envelope/attachment

Headers

Header	Required	Description
Authorization	Yes	Bearer authorization token
Content-Type	Yes	multipart/form-data
Mailbox	No	UUID of the current mailbox context

Query parameters

Parameter	Type	Required	Description
type	string	No	File category: all, document, file, image, or archive

Request

Send the file as multipart/form-data in the required file field.

Field	Type	Required	Description
file	binary	Yes	File to upload

Request example

curl --request POST \
  "https://{baseUrl}/api/v1/envelope/attachment?type=document" \
  --header "Authorization: Bearer {token}" \
  --header "Mailbox: {mailboxUuid}" \
  --form "file=@contract.pdf"

Let the HTTP client generate the multipart boundary automatically.

Response

The endpoint returns 201 Created with the uploaded attachment details.

{
  "filename": "contract.pdf",
  "attachmentId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "filesize": 204800,
  "contentType": "application/pdf",
  "updatedPdf": "string"
}

Field	Type	Description
filename	string	Name of the uploaded file
attachmentId	UUID	Identifier of the uploaded attachment
filesize	integer	Uploaded file size in bytes
contentType	string	MIME type of the uploaded file
updatedPdf	byte string	Updated PDF data when included in the response

Attachment references

Set attachmentUuid to the returned attachmentId.

External document

Use the attachment as an external envelope document:

<document
  id="{documentId}"
  attachmentUuid="{attachmentId}"
/>

File field

Use the attachment as a file field value:

<document id="{documentId}">
  <field
    name="File"
    attachmentUuid="{attachmentId}"
  >contract.pdf</field>
</document>

Status codes

Code	Description
201	Attachment uploaded successfully
400	Invalid request body, query parameter, or headers
401	Missing, invalid, or expired authorization token
403	No access to the specified mailbox
413	Uploaded file exceeds the allowed size

Related topics

• XML payloads

• Templates and reusable IDs

• Envelope fields

• Send your first envelope

• Send Envelope

• Fill Envelope