Using S3

This section explains how to work with Amazon Simple Storage Service (S3) to store digital files in the cloud and attach them to items in the Digital Archive. The examples are from the Southwest Harbor Public Library (SWHPL) Digital Archive.

To use S3, you must enable the AvantS3 plugin which integrates S3 with the Digital Archive.

While S3 is not as straightforward or as easy to use as other cloud storage services like Google Drive or Dropbox, it is a fast, safe, economical, and powerful alternative. Most importantly, it is integrated with the Digital Archive thanks to the AvantS3 plugin.

For organizations that have two or more archivists, S3 is more economical than services like Dropbox which require that you pay extra for additional users. With S3, you can create additional users for no additional cost and assign each user either full or read-only access to your files.

S3 advantages

These are the primary advantages that S3 offers for a Digital Archive site:

  • Safe storage of archival digital assets such as original scans and other types of files.
  • Online access to digital assets by archivists working remotely.
  • Easy access to digital assets with a single click from the Digital Archive.
  • Easy one-click attachment of files to Digital Archive items.
  • Automatic downsizing of JPEG files when attached to an item.

Logging into S3

Follow the steps below to log in to the Amazon Web Services (AWS) Management Console for S3, subsequently referred to as simply the S3 console.

  • First log in to the Digital Archive and go to the Dashboard.
  • Then click the S3 Management Console link to get to the AWS login page.
  • You can also access the S3 console by going directly to


If you are already logged into S3, the link will take you to the S3 console.

On the AWS sign-in page, enter your credentials and click the Sign in button.


After you click the Sign in button, the S3 console appears as shown below.


In the screenshot above, the bottom of the S3 console shows the two kinds of storage used for the Digital Archive as will be explained in the following sections.

  • Clicking on Accessions gets you to Accessions Storage
  • Clicking on Database gets you to Items Storage

Storage for Items and Accessions

S3 is not a traditional folder-oriented hierarchical file system like you are familiar with on a PC or a Mac. S3 storage is implemented using things called buckets, objects, and prefixes, but fortunately, these can be thought of and viewed using familiar terms like folders, subfolders, and files. You do however have to be very careful when working with S3 as explained in the S3 limitations and cautions section.

SWHPL's S3 storage for the Digital Archive is in a bucket named swhpl-digital-archive. It is divided into two top-level storage folders:

  • Items Storage
  • Accessions Storage

Items Storage is used to store the files for individual Digital Archive items whereas Accessions Storage is used to store all of the files for an accession and its sub-accessions.

Items Storage folder

The Items Storage folder swhpl-digital-archive > Database stores files that are associated with individual items in the Digital Archive database, but only for items that are not part of an accession. All files for a single item are kept together in a subfolder that has the same name as the item's identifier number. For example, the files for item 12139 are stored in a folder named 12139.

Grouping folders

At the top level of the Items Storage folder are 16 grouping subfolders named 1000, 2000, up to 16000. Each of these folders can contain up to 1,000 subfolders for individual items. For example, folder 12000 contains folders for items 12000, 12001, 12002 and so on. The grouping folders make it easy to find an item's folder. If you are looking for the files for item 12139 you first go to the 12000 grouping folder and then look for 12139.

Image item example

The screenshot below shows the files for item 12139 which is a photograph.


The four files associated with item 12139 are as follows:

  • 12139.jpg is a web-sized copy of the photograph downsized from SWHPL-12139-CFS.jpg.
  • access-12139.txt contains information about the item from the Microsoft Access database.
  • SWHPL-12139-CFS.jpg is a high-resolution, post-processed copy of SWHPL-12139-SCAN.tif.
    CFS (Cleaned For Study) is a SWHPL term which means that the images may have been cropped, straightened, retouched, or had adjustments such as contrast improvement.
  • SWHPL-12139-SCAN.tif is the large scanner file, 30.8 MB, whereas the other files are smaller.

Other items may have more or fewer files, but this example is typical. Each file serves a purpose:

  • Use 12139.jpg as the web-size image for the Digital Archive.
  • To see the original scan (archival image), view SWHPL-12139-SCAN.tif.
  • To make a print or provide someone with a high-resolution file, use SWHPL-12139-CFS.jpg.
  • The original metadata for the item is preserved in access-12139.txt.

Reference item example

The next example is for Reference Item 16023. The files for a Reference Item usually include a Word document (called a reference sheet) used to record and format the information, and a PDF version of the Word document for use in the Digital Archive. There may be other files as well such as related research materials like the notes-to-work-from document in the example below.


Keeping the original Word document together with the PDF makes it easy for an archivist to update the Reference Item if necessary. They update the Word document, create a new PDF, upload both files to S3, and then attach the PDF to the item to replace the old PDF.

Accessions Storage folder

The Accessions Storage folder swhpl-digital-archive > Accessions stores files that belong to an accession or sub-accession. At the top level of the Accessions Storage folder are subfolders having a four-digit number that matches an accession number for a primary accession in the Accessions table. If an accession has sub-accessions, folders for the sub-accessions are stored in the primary accession's folder. Learn about accessioning.

For example, primary accession 2026 has a top-level folder in the Accessions Storage folder and each of its sub-accessions has its own subfolder: 2026_01, 2026_02, 2026_03, and 2026_04. The S3 folder for the primary accession 2026 looks like this:


If you click on sub-accession 2026_04, you'll see its files as shown in the screenshot below.


An accession folder can contain any number of files of different types. The example above was used for clarity because it only has seven files, but typically there can be a lot more. Keeping all the files for an accession together makes it easy for an archivist to learn what files are in the accession and to find a file of particular interest.

Which kind of storage to use

Whether you store files in Items Storage versus Accessions Storage depends on whether the files are for an accession or for an item that does not belong to an accession. Here are the rules.

When to use Items Storage

You create a subfolder in the Items Storage folder only when both of these conditions are true:

  • You are adding a new item to the Digital Archive.
  • The item's files do not belong to an accession.

Here are examples of when you need to create a new subfolder in the Items Storage folder:

  • Adding a new item from files in the digital backlog.
  • Adding a new item from digital files that came from your camera.
  • Adding a new Reference Item that has a PDF file created from a Word document.

In the three examples above, the item files are not part of an accession and thus are not in Accessions Storage. Therefore, they must be put into Items Storage.

When to use Accessions Storage

You create a subfolder in the Accessions Storage folder only when adding a new accession.

If after you have created an accession, you add an individual item to the Digital Archive, and that items files are part of the accession, the files you attach to the item come from the accession's folder. You don't create a folder for the item in Items Storage. If you need to create additional files while curating the item, for example, a JPEG version of a TIFF file, you add those files to the accession's folder.

Special cases

By following the rules above, an item's files will either be in Accessions Storage or in Items Storage, but not in both places. However, there are some cases where a file could be stored in both places.

The first case is when you find a file in an accession that should be added to an existing item, but that item is not part of the accession. In that case, you need to make a copy of the file and store it in the item's folder in Items Storage. If the file is a large TIFF, you only need to copy a small JPEG version of the file to the item's folder.

The second case has to do with items that are part of an accession, but were added to the Digital Archive before the Avant S3 plugin had support for accessions. Some of the files for those items might be in both Accessions Storage and in Items Storage. You can detect an item like this because when you view it, you'll see an S3 link next to both the item's identifier and its accession number whereas for other items, the link only appears next to one or the other.

Uploading files to S3

The discussion so far has been about using files that are already in S3. This section explains how you upload files to S3. The discussion assumes that you are already logged into S3.

Create a new S3 folder

If the folder that you want to upload files to does not yet exist, create it following the steps below.

  • Determine the name of the new folder:
    • For an item, the folder name is the item's identifier number. As such, you need to first add the item to the Digital Archive so that you know its identifier before you can create an S3 folder for the item.
    • For an accession, the folder name is the accession number or sub-accession number.
  • Go to the S3 folder that will contain the new folder.
    • For an item, the containing folder is swhpl-digital-archive > Database > ##### where ##### is the item's grouping folder.
    • For a primary accession, the containing folder is swhpl-digital-archive > Accessions.
    • For a sub-accession, the containing folder is swhpl-digital-archive > Accessions > #### where #### is the number of the primary accession.
  • Click the S3 console's Create folder button to get to the page shown below.


On the Create folder page, type the new folder name in the Folder name field and click the
Create folder button. After the folder has been created, you can go to it by clicking the folder name link in the upper-left where it says "Successfully created folder." Or you can navigate to the new folder in the usual way.


Upload files to an S3 folder

Follow these steps to get files from your computer into an S3 folder:

  • In the S3 console, go to the S3 folder. If the folder does not exist, create the folder.
  • On your computer, open the folder that contains the files to be uploaded.
  • Drag files from your computer folder onto the S3 page.

The entire screen becomes a drop target as shown in the screenshot below.


As an alternative to dragging files to upload, you can click the S3 Upload button to go to an S3 page that will let you browse for files or a folder on your computer.

After you drag the files, an upload confirmation page appears as shown below. Verify that the files it shows are the ones you want to upload and then click the Upload button.


During the upload, a progress bar appears at the top of the page as shown below. When the upload completes, a status page will appear to let you know that the upload succeeded, or if there were any errors, to explain what went wrong.


Attaching S3 files to items

You can attach S3 files to an item using the Digital Archive as shown in the next screenshot.

To attach S3 files to an item:

  • Edit the item
  • Choose the Files tab
  • Check the box next to each file you want to upload
  • Click the Save Changes button


When you click the Save Changes button, the AvantS3 plugin will:

  • Download the checked files from Amazon S3 to your Digital Archive server.
  • Downsize JPEG images to be 1200px on the long edge.
  • Attach the files to the item.

After the save, when you edit the item again, the Files tab will appear as shown below.


In the screenshot above, note that the Action column says Replace existing file whereas in the previous screenshot it said Add to item. That's because the Digital Archive knows which S3 files can be used as new attachments and which are already attached. This makes it easy to tell if you inadvertently forgot to attach an S3 file to the item.

Which files appear in the Files tab

The files that appear in the Files tab come from:

In the previous example, the files came from Items Storage. The screenshot below shows files that come from Accessions Storage.


For both Items and Accessions storage, files that can be attached to the item have a checkbox next to them. Files without a checkbox are ones the Digital Archive, and browsers in general, do not support such as TIFF files and Word documents.

The latest version of AvantS3 supports TIFF files. When you choose a TIFF file from the list, AvantS3 downloads the file from S3, converts it to JPEG, and resizes it. It then attaches the resized JPEG file to the item. This saves you from having to perform all those steps manually.

Reorder or delete attachments

The steps for reordering and deleting S3 attachments are the same as explained for uploading files to the Digital Archive when not using S3. However, when you delete an attachment, the file itself remains in S3 and continues to show up in the S3 files list. That's because the list is only a reflection of what's stored on S3.

Replace an attached file with an updated version

To replace an attached file with a newer version having the same file name:

  • Upload the newer file to S3.
  • Edit the item and go to the Files tab.
  • Check the box for the file that got updated.
  • Click the Save Changes button.

The Digital Archive will replace the older file with the newer one using the same file name. You don't need to first delete the older file as you do when not using S3.

Accessing S3 files

The previous sections have been about uploading files to S3 and attaching S3 files to Digital Archive items. It is often the case, however, that you simply want to see the S3 files for an item or an accession.

For example, suppose a patron is viewing item 16693 and requests a high-resolution copy of the photograph. To immediately access the high-resolution image, all you have to do is view the item and click the S3 link as shown by the red arrow in the screenshot below.


Clicking the link takes you to the S3 folder where the file is stored as shown below. You can then download the file to make it available to the person who requested it.


When an item's files are in Items Storage instead of in Accessions Storage, the S3 link appears next to the identifier number, as shown below, instead of the accession number. The S3 links only appear when you are logged-in to the Digital Archive as an administrator.


S3 limitations and cautions


There are some things to be aware of when using the S3 console.

  • When you delete a file, a hidden version of the file remains.
  • When you delete a folder, a hidden version of the folder and all of its file remains.
  • When you rename a folder, a hidden version of the original folder remains.

It's like this for safety reasons, so that you can undo a mistake. However, if you rename, or move a folder that contains a lots of files, you are actually doubling the amount of storage required for those files. If you delete a file or folder, you are not actually freeing up any space.


The S3 console:

  • Does not provide a way to preview an image (you have to download the image to view it).
  • Will only let you download one file at a time.
  • Makes it difficult to permanently delete a file or folder.

To work around these limitations, use the S3 Browser utility described below.

Deleting files and folders with the S3 console

This section explains how to delete, or permanently delete, a file using the S3 console. As you will see, deleting a file only marks it deleted and hides the file, but keeps the old version of the file. Permanently deleting a file removes it from S3, after which, the file cannot be recovered.

Delete a file, but keep a copy of the deleted version

  • Disable the Show versions option.
  • Select the file by checking its box.
  • Click the Delete button.
  • On the Delete object page type delete in the Delete objects? field.
  • Click the Delete objects button.


After the deletion, the deleted file will no longer display as shown below.


If you enable the Show versions option, you'll see the deleted file along with its delete marker.


To restore the file, delete its delete marker.

Permanently delete a file

  • Enable the Show versions option.
  • Select the file by checking its box.
  • Click the Delete button.
  • On the Delete object page type permanently delete in the Delete objects? field.
  • Click the Delete objects button.


Notice the difference between the screenshot above, and the first screenshot in the previous section where the Show versions option was disabled. When the option is enabled, you see the file's version ID. Because you have checked the box for a specific version of the file, the file will be permanently deleted. In the previous section, since no version ID was showing, the file was only marked as deleted.

Permanently delete a folder

  • Go into the folder to view its files (don't delete the folder itself).
  • Enable the Show versions option.
  • Select all the files by checking the box that is to the left of the Name column header.
  • Click the Delete button.
  • On the Delete object page type permanently delete in the Delete objects? field.
  • Click the Delete objects button.

If the folder contains subfolders, you'll need to first permanently delete each subfolder. If a folder contains more than 300 files, you'll have to delete the files in groups of 300 until the folder is empty. For a folder with lots of files and subfolders, it's much faster and easier to use the
S3 Browser utility.

Deleting all of the files in a folder deletes the folder itself if the folder was uploaded to S3. The folder won't be deleted if you created it using the Create folder button or the S3 Browser utility. If you explicitly delete the folder, it won't appear in the S3 console when the Show versions option is disabled, but you'll still see it when the option is enabled. To permanently delete the folder, you'll need to use the S3 Browser utility.

S3 Browser utility

S3 Browser is a 3rd-party Windows utility that lets you perform tasks that are difficult or not possible using the AWS Management Console for S3.

Preview an image

To preview and image:

  • Select the file
  • Choose the Preview tab in the lower panel


Download multiple files

To download multiple files:

  • Select the files
  • Click the Download button
  • On the Select Folder dialog, choose where to put the files


Permanently delete a folder

This feature requires S3 Browser Pro configured with admin credentials.

To permanently delete a folder:

  • Select the folder.
  • Click the Delete button located below the file/folder window of the upper panel.
  • Click the Yes button on the confirmation dialog.
  • Choose the deleted folder's parent folder.
  • Choose the Versions tab in the lower panel.
  • Wait for the version information to load.
  • Choose Show only deleted files from the Filters dropdown at lower right.
  • Wait for the filtered version information to load.
  • Each key in the list should show (deleted) as shown in the screenshot below.
  • Select all of the keys by using Ctrl-A.
  • Delete the keys using the Delete button in the lower panel.
  • Click the Yes button on the confirmation dialog.


This solution works even if the folder contains more than 300 files and/or if it contains subfolders.

Permanently delete an empty deleted folder

This feature requires S3 Browser Pro configured with admin credentials.

Deleting all of the files in a folder normally deletes the folder itself if the folder was uploaded to S3. The folder won't be deleted if you created it using the S3 console of the S3 Browser utility.

To permanently delete the folder:

  • Follow the steps above for permanently deleting a folder but the only keys you'll need to select will be for the folder itself.