Attach (Geo)Arrow and/or (Geo)Parquet JavaScript dependencies to a widget.

Pipe-friendly functions to attach (Geo)Arrow and/or (Geo)Parquet JavaScript dependencies to a widget created with createWidget.

Usage

attachGeoarrowDependencies(widget)

attachGeoarrowDependency(widget)

attachArrowDependency(widget)

attachParquetWasmDependencies(widget)

Arguments

widget

A widget created with createWidget.

Value

The widget including Arrow, Geoarrow and/or parquet-wasm JavaScript dependencies.

Details

Attaching the parquet-wasm JavaScript dependency differs from attaching the other dependencies. In order to enable reading .parquet files in the browser we declare an async function parquet2arrow at the window level that can be used to read parquet data into an Arrow memory table in the browser. As such, attachParquetWasmDependencies() will also attach the arrow and geoarrow dependencies.

So, in the browser, we can use this as follows:

  fetch(<(geo)parquet-url>)
    .then(pq => window.parquet2arrow(pq))
    .then(arrow_table => {

     // code to work with arrow table

    });

Examples

library(listviewer)

wgt = jsonedit(
  list("Just some dummy text")
  , elementId = "lv-example"
)
attachGeoarrowDependencies(wgt)


## open the resulting page in the browser and inspect the page source, e.g.
## by pressing <Ctrl + u>. You should see two lines like:

# <script src="lib/apache-arrow-js-19.0.1/Arrow.es2015.min.js"></script>
# <script src="lib/geoarrow-js-0.3.2/geoarrow.umd.min.js"></script>

## !Version numbers of the JavaScript dependencies may differ!