Use case: Read the download url for a file attachment of an annotation

Before you start

Before you retrieve a download URL for a file attachment, ensure you have completed the following prerequisites:

  1. Verify Permissions: Confirm that you have the necessary rights to access the attachment. This typically requires having read access to the annotation containing the attachment.
  2. Identify the Attachment: Have the unique identifier of the specific attachment you need to download. You'll need this to request the correct download URL.
  3. Understand URL Expiration: Be aware that download URLs provided by the Collaboration system are typically temporary and expire after a certain period (usually 24 hours or less). They should be used promptly rather than stored long-term.
  4. Storage Considerations: Ensure you have sufficient local storage if you plan to download large files, especially when implementing batch download functionality.
  5. Set Up SDK Environment: Ensure your Unity environment is properly configured with the Collaboration SDK to interact with the annotation system.

How do I...?

Get a download URL for a specific attachment

To retrieve a download URL for an identified attachment:

  1. Obtain the Project Identifier: Ensure you have the correct project identifier (GUID) for the project.
  2. Obtain the Asset Identifier: Ensure you have the correct and complete asset identifier (GUID) for the asset.
  3. Obtain the Attachment ID: Ensure you have the unique identifier for the specific attachment you want to get the download url for.
  4. Request the Download URL: Use the SDK to request a temporary download URL for the attachment.
  5. Use the URL Promptly: Remember that the download URL has a limited validity period.

Example:

var response = await annotationManagement.ReadAnnotationFileAttachmentDownloadUrlAsync(
  projectId: projectId,
  annotationId: annotationId,
  attachmentId: attachmentId,
  cancellationToken: cancellationToken);

var downloadUrl = response.Url;

For more information on working with attachments, see the documentation on creating attachments and updating attachments.