---
sourceDocument: Xanadu API Reference
sourceDocumentLink: https://servicenow-prod.fluidtopics.net/r/xanadu/api-reference

 Release :

    - xanadu

ft:locale :

    - en-US

ft:publication_title :

    - Xanadu API Reference

ft:clusterId :

    - crapiref

bundleId :

    - crapiref

workflow :

    - Creator


---

# Retrieve attachments and attachment metadata

# Retrieve attachments and attachment metadata {#ariaid-title1}

* Release version: Xanadu
* 
* Updated August 1, 2024
* 
* ![](https://www.servicenow.com/docs/portal-asset/ico-clock) 2 minutes to read

The NowAttachmentService API enables you to perform CRUD operations
on attachments and retrieve attachment metadata from your ServiceNow
instance.
Using this API you can:

* Upload attachments to your ServiceNow instance and associated them to a specific record.
* Download one or more attachments.
* Delete attachments.
* Validate an attachment by comparing the computed hash of the attachment to the expected hash.
* Download attachment metadata. This metadata is generated by your ServiceNow instance when an attachment is uploaded.
{#mobsdk-ios-retrieve_attach_metadata__ul_l5y_qjw_3qb}

For additional information on working with attachments, see [Attachment API](https://servicenow-prod.fluidtopics.net/6cG37dgmR1vwJCbI7a6lCg#c_AttachmentAPI "The Attachment API provides endpoints that allow you to upload and query file attachments.").

All [NowAttachmentService](https://servicenow-prod.fluidtopics.net/MsIRssV78dlFdkKVybmzNg#NowAttachmentServiceiOSAPI "The NowAttachmentService class provides functions that enable you to upload and query attachments that are associated with records within a table on a ServiceNow instance.") methods provide three implementations for returning results data. One that calls a completion handler with the return results, one that preforms an
async/await, and another that returns a [Combine](https://developer.apple.com/documentation/combine) publisher (deprecated). For example, each upload() method uploads and associates a specified attachment to a specified record. However, the [NowAttachmentService - upload(data: Data, configuration: NowAttachmentUploadConfiguration, progressUpdate: @escaping ProgressUpdate, completion: @escaping (Result<NowAttachmentMetadata, NowDataError>))](https://servicenow-prod.fluidtopics.net/MsIRssV78dlFdkKVybmzNg#NAttServiOS-upload_O_O_O_O "Uploads the attachment data and attaches it to a record in a table as specified in the upload configuration.") method calls a completion handler with the return results, the [NowAttachmentService - upload(data: Data, configuration: NowAttachmentUploadConfiguration, progressUpdate: @escaping ProgressUpdate) async throws](https://servicenow-prod.fluidtopics.net/MsIRssV78dlFdkKVybmzNg#NAttServiOS-upload-async_O_O_O_O "Uploads the attachment data and attaches it to a record in a table as specified in the upload configuration.") method performs an async/await, and the [NowAttachmentService - upload(data: Data, configuration: NowAttachmentUploadConfiguration, progressUpdate: @escaping ProgressUpdate)](https://servicenow-prod.fluidtopics.net/MsIRssV78dlFdkKVybmzNg#NAttServiOS-upload_O_O_O "Uploads the attachment data and attaches it to a record in a table as specified in the upload configuration.") method returns a Combine publisher.  
Before you are able to use the NowAttachmentService API, you must import NowData and then initialize a NowAttachmentService object.

    // Import the NowData framework
    import NowData

    func makeAttachmentService(instanceUrl: URL, 
      completion: @escaping ((Result<NowAttachmentService, NowServiceErrors>) → Void))

## Attachment metadata pagination {#mobsdk-ios-retrieve_attach_metadata__section_stt_34w_3qb}

You can use the NowAttachmentService methods to download attachment
metadata for one or more attachments. When downloading metadata from multiple attachments,
you may want to use the [NowAttachmentService - attachmentMetadataPaginator(filter: Filter, limit: Int)](https://servicenow-prod.fluidtopics.net/MsIRssV78dlFdkKVybmzNg#NAttServiOS-attachMetadataPag_S_I "Retrieves the metadata for all the attachments that meet the specified criteria and returns a Paginator object for iterating through the pages of the returned metadata.") method, which returns a [Paginator](https://servicenow-prod.fluidtopics.net/2PI_SgczzCsJPmA6W~Hulw#PaginatorIOSAPI "The Paginator class provides methods for iterating through a record set returned by a call to the ServiceNow Table API through the NowTableService. It is the object that is returned by the NowTableService paginator() methods. Do not call this method outside of that environment.") object that enables you to easily iterate over the potentially large
amount of data that is returned. You typically use paginated return results to provide
infinite scroll capabilities for data presented inside a UITableView, a UICollectionView
(UIKit), or a List (SwiftUI), or to simplify page iteration of results in general.  
After obtaining a Paginator object, subscribe to its publisher to start receiving data.

    paginator.publisher
      .subscribe(on: DispatchQueue.global())
      .receive(on: DispatchQueue.main)
      .sink { ... }
      .store(in: &subscriptions)

The returned Paginator object provides the following methods that enable you to page through the returned records:

* first()
* last()
* next()
* previous()
* reset()

{#mobsdk-ios-retrieve_attach_metadata__ul_pyb_2w3_3qb}  
Note:  
Some Paginator methods may throw an exception, such as when there are no more pages to fetch.

In addition, the Paginator object provides properties
that enable you to obtain insights into the paginated data. For additional details on these
properties and the available methods, see [Paginator API - iOS](https://servicenow-prod.fluidtopics.net/2PI_SgczzCsJPmA6W~Hulw#PaginatorIOSAPI "The Paginator class provides methods for iterating through a record set returned by a call to the ServiceNow Table API through the NowTableService. It is the object that is returned by the NowTableService paginator() methods. Do not call this method outside of that environment.").