IISG Data Services¶
The International Institute of Social History (IISG) holds archives, library material, serials, posters, photographs and audiovisual collections on the history of work, workers and social movements. This site explains how to get that metadata out in bulk and how to query it as Linked Data.
Beta¶
Beta
This documentation is new. Pages, examples and URLs may still change. Feedback is welcome at data@iisg.nl.
The SPARQL endpoint in the examples is a test endpoint. IISG's
official knowledge graph is at iisg.amsterdam/kg,
with its SPARQL service at https://api.druid.datalegend.net/datasets/IISG/iisg-kg/services/iisg-kg/sparql. For testing purposes,
this documentation uses another endpoint, https://sparql.zijdeman.nl, which
runs a newer version of the graph. The IRIs are the same on both, but
not every example gives the same results on the official endpoint. For
example, names of topics and places are not yet available there.
The knowledge base viewer is experimental too. The viewer runs on the same test endpoint. Its address, look and features may change.
The OAI-PMH endpoint is not affected: it is IISG's production service.
Which service should I use?¶
| I want to… | Use | Status |
|---|---|---|
| Browse records and their links in a web page | Knowledge base viewer | Experimental |
| Build my own web interface or app on top of the data | The SPARQL endpoint. The viewer is an example: its source is a single web page that queries SPARQL straight from the browser | Experimental (test endpoint) |
| Ask questions across collections ("all posters about women's suffrage made in the Netherlands") | SPARQL endpoint | Experimental (test endpoint) |
| Download a whole collection, or keep a local copy in sync | OAI-PMH | Production |
All of these describe the same records. The viewer is a web interface on top of the knowledge graph. It has no server of its own: it sends SPARQL queries from your browser, so anyone can build a similar interface. The SPARQL endpoint lets you query that graph directly. The graph itself is rebuilt every night by harvesting the OAI-PMH endpoint, converting the records to RDF (mainly schema.org and RiC-O) and linking them to persons, organisations, places and topics. OAI-PMH serves the source: the catalogue records as the cataloguers made them (MARC, EAD, Dublin Core). The IRI reference shows how an OAI identifier becomes a knowledge-graph IRI.
Tutorials¶
- OAI-PMH: explore the endpoint, harvest a set, keep it up to date, and follow a record into the knowledge graph.
Contact¶
Questions about the OAI-PMH endpoint or the knowledge graph go to data@iisg.nl. To report a problem with this documentation, open an issue on GitHub.