IIIF Change Discovery API

Introduction

The IIIF Change Discovery API provides a mechanism to discover changes to resources. The Activity Streams 2.0 specification is used to describe these changes, through an OrderedCollection (an interlinked set of pages) in which each OrderedCollectionPage contains a certain number of change events.

The OrderedCollection serves as a navigational starting point for discovery, and provides a reference to the last OrderedCollectionPage within the collection. The last OrderedCollectionPage describes the most recent event(s), while the pages before that describe older event(s). Additionally, each page may contain a reference to the previous and/or the next page in a collection. Note that the API specification recommends to begin processing with the last page and that providing a reference to the first page is optional.

The client should keep track of the pages or events that have already been processed before. The client is also expected to interpret the types of change to a resource and infer what the current state of the resource is, and it should make intelligent decisions whether an event is still relevant or applicable to a resource.

Implementation

Rijksmuseum uses a IIIF Change Discovery API to facilitate the discovery of any changes to the metadata of e.g. its collection objects and bibliographic resources.

The API serves pages that contain a maximum of one hundred ordered events. Each event with a timestamp, the type of change and the persistent identifier of the resource that underwent the change. The actual metadata of the resource is not included; the content can be obtained by resolving the persistent identifier of the resource.

Datasets

The implementation also includes support for datasets, which scopes an OrderedCollection to events about an opiniated selection of resources. Each dataset is assigned a unique dataset number. Rijksmuseum registers certain datasets (e.g. as DCAT entries in the NDE Dataset Register) or communicates relevant dataset numbers to interested parties directly. However, discovery of datasets is currently not available.

Access

There are two endpoints available, a UAT and a production endpoint.

Intented Use	Resource Scope	Root Location
Acceptance Test	All	https://acc.data.rijksmuseum.nl/cd/collection.json
Acceptance Test	Dataset	https​://acc.data.rijksmuseum.nl/cd/dataset number/collection.json
Production	All	https://data.rijksmuseum.nl/cd/collection.json
Production	Dataset	https​://data.rijksmuseum.nl/cd/dataset number/collection.json

Examples

OrderedCollection

note

The following example does not represent an actual API response.

{
    "@context": "http://iiif.io/api/discovery/1/context.json",
    "@type": "OrderedCollection",
    "first": {
        "id": "http://data.rijksmuseum.nl/cd/pages/collection/forward/1.json",
        "type": "OrderedCollectionPage"
    },
    "id": "http://data.rijksmuseum.nl/cd/collection.json",
    "last": {
        "id": "http://data.rijksmuseum.nl/cd/pages/collection/backward/500.json",
        "type": "OrderedCollectionPage"
    }
}

OrderedCollectionPage

note

The list of events was reduced to keep the example small and does not represent an actual API response.

{
    "@context": "http://iiif.io/api/discovery/1/context.json",
    "id": "http://data.rijksmuseum.nl/cd/pages/collection/backward/500.json",
    "orderedItems": [
        {
            "endTime": "2024-12-10T16:00:00.723333",
            "object": {
                "id": "http://data.rijksmuseum.nl/2987654"
            },
            "type": "Create"
        },
        {
            "endTime": "2024-12-10T16:00:00.656666",
            "object": {
                "id": "http://data.rijksmuseum.nl/2765432"
            },
            "type": "Create"
        }
    ],
    "partOf": {
        "id": "http://data.rijksmuseum.nl/cd/collection.json",
        "type": "OrderedCollection"
    },
    "prev": {
        "id": "http://data.rijksmuseum.nl/cd/pages/500/backward/400.json",
        "type": "OrderedCollectionPage"
    },
    "type": "OrderedCollectionPage"
}