> ## Documentation Index
> Fetch the complete documentation index at: https://docs.iinkedsign.com/llms.txt
> Use this file to discover all available pages before exploring further.

# External data

> Learn how to attach external data to your signing packages to streamline integration.

## Overview

You can attach external data to signing packages and documents to help integrate with your existing systems. This allows you to associate your internal identifiers or metadata with the packages and documents managed through our API.

## Attaching external data to packages

When creating a signing package, you can attach external data to it using the `externalData` field in the add package request.
This data can be any set of JSON-serializable key-value pairs and will be stored with the package.

```http Request highlight={18-21} theme={null}
POST /packages/add
{
    "name": "New Package",
    "type": "concurrent",
    "signers": [
        {
            "firstName": "Signer",
            "lastName": "One",
            "email": "signer.one@example.com"
        }
    ],
    "documents": [
        {
            "fileName": "document.pdf",
            "fileId": "51400d7a-4f34-4844-9138-46a365130f97"
        }
    ],
    "externalData": {
        "internalId": "12345",
        "customerId": "67890"
    },
    "returnPackage": false
}
```

When you call future package-related endpoints, such as retrieving package details or checking the package status, the `externalData` field will be included in the response.

```http Request  theme={null}
GET /packages/{packageId}/status
```

```json Response highlight={4-7} theme={null}
{
    "packageId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
    ...
    "externalData": {
        "internalId": "12345",
        "customerId": "67890"
    }
}
```

Package related webhooks will also include the `externalData` field in their payloads, allowing you to access this information during webhook processing.

```json Payload highlight={3-6} theme={null}
{
	"packageId": "24428e41-8b96-40cc-96e6-b74c7c539fcb",
    "externalData": {
        "internalId": "12345",
        "customerId": "67890"
    },
	"action": "package_add",
	"eventId": "e9b8fe63-4a19-4446-bd6e-cb34b72b411e",
	"eventOwnerOrganizationId": "24261ee6-5f66-4692-ba49-533c9b58999b",
	"eventOwnerMemberId": "3e09a4ce-577c-492c-ba7c-c1ebf825f9b5",
	"eventTime": "2022-02-23T20:19:28.9357901Z"
}
```

## Attaching external ID to documents

You can also attach an external ID to individual documents within a package using the `externalId` query parameter when uploading files.

```http Request highlight={1} theme={null}
POST /files/upload?externalId=doc12345
Content-Type: multipart/form-data
Content-Disposition: form-data; filename="document.pdf"
<FILE_CONTENTS>
```

```json Response highlight={5} theme={null}
{
  "files": [
    {
      "fileId": "5997903d-2975-4c71-84d4-536255529b66",
      "externalId": "doc12345",
      "name": "document.pdf",
      "fileName": "document.pdf",
      "type": "temporary"
    }
  ]
}
```

When you later retrieve package details, the `externalId` will be included in the response.

```http Request theme={null}
GET /packages/{packageId}/status
```

```json Response highlight={7} theme={null}
{
    "packageId": "24428e41-8b96-40cc-96e6-b74c7c539fcb",
    ...
    "documents": [
        {
            "documentId": "ad8eac67-94e9-481b-a799-7396b447b8eb",
            "externalId": "doc12345",
            "fileName": "document.pdf",
            ...
        }
    ]
}

```