What is Item Level Versioning?
Versioning is a new functionality to build the history of an item. Users will have the opportunity to create new version of an existing item any time the will make a change.
Supported in 7.1 or above
Item level versioning was not fully supported in DSpace 7.0 (you were only able to view existing versions). It was restored in DSpace 7.1. See DSpace Release 7.0 Status
Item Level Versioning on Entities configuration
Configurable Entities are supported in Item Level Versioning support starting from version 7.3. More details about the configuration specific to Configurable Entities can be found on that page.
AIP Backup & Restore functionality only works with the Latest Version of Items
If you are using the AIP Backup and Restore functionality to backup / restore / migrate DSpace Content, you must be aware that the "Item Level Versioning" feature is not yet compatible with AIP Backup & Restore. Using them together may result in accidental data loss. Currently the AIPs that DSpace generates only store the latest version of an Item. Therefore, past versions of Items will always be lost when you perform a restore / replace using AIP tools. See https://github.com/DSpace/DSpace/issues/4751.
DSpace 6+ changed the way Handles are created for versioned Items
Starting with 6.0, the way DSpace crates Handles for versioned Items was changed. If you want to keep the old behavior of DSpace 4 and 5 you have to enable the
VersionedHandleIdentifierProviderWithCanonicalHandles in the XML configuration files
[dspace]/config/spring/api/identifier-service.xml. See IdentifierServiceOverride below for details and the comments in the configuration file.
Enabling Item Level Versioning
By default, Item Level Versioning is enabled in DSpace 7.1. You may choose to disable it by updating this configuration in your local.cfg:
The Item Level Versioning implementation builds on following requirements identified by the stakeholders who supported this contribution: Initial Requirements Analysis
- What should be Versionable
- Versioning happens at the level of an Individual Item
- Versioning should preserve the current state of metadata, bitstreams and resource policies attached to the item.
- Access, Search and Discovery
- Only the most recent version of an item is available via the search interface
- Previous versions of Items should continue to be visible, citable and accessible
- The Bitstreams for previous versions are retained. If something was once retrievable, it should always be retrievable.
- Each version of an Item is represented by a separate "versioned" identifier
- A base "versionhistory" Identifier points to the most recent version of the Item.
- A revision identifier also exists that is unique to the specific version.
- When a new version of an Item is deposited, a new revision identifier will be created.
- On the item page, there is a link to view previous/subsequent versions.
- By examining the metadata or identifiers, it is possible to determine whether an item is the most recent version, the original version, or an intermediate version.
- Access Control and Rights
- Certain roles should be able to generate a new version of the item via submission.
- To submitters, collection manager, administrators will be given to option to create new version of an item.
- Rights to access a specific Item should transmute as well to previous versions
- Rights to access a specific Bitstream should also transmute to previous versions.
- Data Integrity
- The relationships between versions should not be brittle and breakable by manipulating Item metadata records.
- The relationships between versions should be preserved and predictable in various Metadata Exports (OAI, Packagers, ItemExport)
- The relationships between versions should be maintained in SWORD and AIP packaging and be maintained in updates and restorations.
General behaviour: Linear Versioning
From the user interface, DSpace offers linear versioning. As opposed to hierarchical versioning, linear version has following properties:
- A new version can be created started from any available version but will be always be put at the end of the version history (it will be the latest)
- Only one in-progress version can exist at any time. When new version has been created and still needs to pass certain steps of the workflow, it is temporarily impossible to create another new version until the workflow steps are finished and the new version has replaced the previous one.
Creating a new version of an item
Administrators, collection/community administrators and eventually the original submitter can create new versions of an item from the Item View page. By default the original submitter is not allowed to create new version but the permission can be granted with the following property
- Click "Create a new version" from the buttons on the right side of the item page.
- Provide the reason for creating a new version that will later on be stored and displayed in the version summary.
- Your new version is now creates as a new Item in your Workspace. It requires you to go through the submission and workflow steps like you would do for a normal, new submission to the collection. The rationale behind this is that if you are adding new files or metadata, you will also need to accept the license for them. In addition to this, the versioning functionality does not bypass any quality control embedded in the workflow steps.
After the submission steps and the execution of subsequent workflow steps, the new version becomes available in the repository.
Versions can be also managed via the edit item page, in the dedicated versions tab
View the history and older versions of an item
An overview of the version history, including links to older versions of an item, is available at the bottom of an Item View page. The repository administrator can decide whether the version history should be available to all users or restricted to administrators. Since DSpace 6 the repository administrator can decide whether all users should be able to see the version submitter/editor or if this information is restricted and can be seen by administrators only. As this may expose data that my be considered personal (name and email address of the submitter), we encourage everyone to leave the default setting and reveal those information to administrators only.
For every new Version a separate DSpace Item will be created that replicates the metadata, bundle and bitstream records. The bitstream records will point to the same file on the disk.
The Cleanup method has been modified to retain the file if another Bitstream record point to it (the dotted lines in the diagram represent a bitstream deleted in the new version), in other words the file will be deleted only if the Bitstream record processed is the only one to point to the file (count(INTERNAL_ID)=1).
Versioning Service Override
You can override the default behaviour of the Versioning Service using following XML configuration file, deployed under your dspace installation directory:
In this file, you can specify which metadata fields are automatically "reset" (i.e. cleared out) during the creation of a new item version. By default, all metadata values (and bitstreams) are copied over to the newly created version, with the exception of dc.date.accessioned and dc.description.provenance. You may specify additional metadata fields to reset by adding them to the "ignoredMetadataFields" property in the "versioning-service.xml" file:
Identifier Service Override
Persistent Identifiers are used to address Items within DSpace. The handle system is deeply integrated within DSpace, but since version 4 DSpace can also mint DOIs. DSpace 4 and 5 supported one type of versioned handle: The initial version of an Item got a handle, e.g. 10673/100. This handle was called the canonical one. When a newer version was created, the canonical handle was moved to identify the newest version. The previously newest version got a new handle build out of the canonical handle extended by a dot and the version number. In the image below you see a version history of an item using this handle strategy.
The canonical handle will always point to the newest version of an Item. This makes sense if you hide the version history. Normal users won't be able to find older versions and will always see just the newest one. Please keep in mind, that older versions can be accessed by "guessing" the versioned Handle if you do not remove the read policies manually. The downside of this identifier strategy is that there is no permanent handle to cite the currently newest version, as it will get a new Handle when a newer version is created.
With DSpace 6 versioned DOIs (using DataCite as DOI registration agency) were added and the default versioned Handle strategy was changed. Starting with DSpace 6 the
VersionedHandleIdentifierProvider creates a handle for the first version of an item. Every newer version gets the same handle extended by a dot and the version number. To stay by the example from above, the first version of an Item gets the Handle 10673/100, the second version 10673/100.2, the third version 10673.3 and so on. This strategy has the downside that there is no handle pointing always to the newest version. But each version gets an identifier that can be use to cite exactly this version. If page numbers changes in newer editions the old citations stay valid.
In DSpace 4 and 5 only the strategy using canonical handles (one handle that always points to the newest version) were implemented. In DSpace 6 the strategy of creating a new handle for each version was implemented. With DSpace 6 this new strategy become the default. The strategy using canonical handle still exists in DSpace but you have to enable the
VersionedHandleIdentifierWithCanonicalHandles in the file
[dspace]/config/spring/api/identifier-serice.xml. With DSpace 6 versioned DOIs were introduced using the strategy that every new version gets a new DOI (extended by a dot and the version numbers for versions >= 2). To use versioned Handle you have to enable DOIs, you have to use DataCite as registration agency and you have to enable the
VersionedDOIIdentifierProvider in the named configuration file.
You can configure which persistent identifiers should be used by editing following XML configuration file, deployed under your dspace installation directory:
No changes to this file are required to enable Versioning. This file is currently only relevant if you want to keep the identifier strategy from DSpace 4 and 5 or if you want to enable DOIs or even versioned DOIs.
Version History Visibility
By default, all users will be able to see the version history. To ensure that only administrators can see the Version History, enable
versioning.item.history.view.admin in the
[dspace]/config/modules/versioning.cfg OR in your
Allowing submitters to version their items
With DSpace 6.0 it became possible to allow submitters to create new versions of their own items. The new versions are going through the normal workflow process if the collection is configured this way. To allow submitters to create new versions of Item they originally submitted, you have to change the configuration property
versioning.submitterCanCreateNewVersion and set it to
true. It is part of the configuration file
/config/modules/versioning.cfg but can be overridden in your
Identified Challenges & Known Issues
Item Level Versioning has a substantial conceptual impact on many DSpace features. Therefore it has been accepted into DSpace as an optional feature. Following challenges have been identified in the current implementation. As an early adopter of the Item Level Versioning feature, your input is greatly appreciated on any of these.
Conceptual compatibility with Embargo
Lifting an embargo currently does not interact with Item Level Versioning. Additional implementation would be required to ensure that lifting an embargo actually creates a new version of the item.
Conceptual compatibility with Item Level Statistics
Both on the level of pageviews and downloads, different versions of an item are treated as different items. As a result, an end user will have the impression that the stats are being "reset" once a new version is installed, because the previous downloads and pageviews are allocated to the previous version.
One possible solution would be to present an end user with aggregated statistics across all viewers, and give administrators the possibility to view statistics per version.
Exposing version history
The version history is added on the bottom of a versioned item page. A repository administrator can either decide to show this to all users, or restrict it to admins only. If it is shown to admins only, an end user will have no way to find the way to an older version. Since DSpace 6 you can also configure if the submitter's name and email address should be part of the version history or if they should be hidden. To show the submitter might actually be useful if the editor account is always a generic institutional email address, but may conflict with local privacy laws if any personal details are included.
In either the
[dspace]/config/modules/versioning.cfg configuration file or your
local.cfg, you can customize the configuration option
versioning.item.history.include.submitter. By default this is set to false, which means that information about the submitter is only viewable by administrators. If you want to expose the submitters information to everyone (which be useful if all submitters uses generic institutional email addresses, but may conflict with local privacy laws if personal details are included) you can set this configuration property to true.