Visualizing uploaded (but not-yet-linked) datasets

[mdeagen]

The SPARQL+Vega charts we currently have (interactive charts with embedded queries of linked data) are the gold standard for contextualized charts.

However, given the (soon) ability to upload structured datasets (csv), it makes sense to support having these datasets as inputs to our viz capabilities as well. I can imagine use cases where charts may be helpful in communicating how the data can be semantically linked to the rest of the database.

The SPARQL+Vega Editor currently handles the "data": {"values": [ ... ] } field with JS, using this.data from the query output.

Vega-Lite also supports "data": {"url": "..." }, which would make sense to use if these datasets have a public-facing url in a preferred format (.csv, .json, .tsv, ...).

We likely need a subclass of sio:Chart to differentiate these different types of charts, embedded query vs. embedded dataURL.

See Vega-Lite Data Documentation for more details.