Reactive reading xlsx files

Is it possible to plot a chart on Shiny using data from XLSX file? It should be reactive, in the sense that, if the XLSX is updated, the chart should be updated.

How can I do it?

Use shiny::fileInput in the UI. You can look at the docs for a simple example of how to do this with a csv - you can just use an Excel file instead.

It's important to note that each time you change the Excel file, you need to reupload it using widget.

This can be realized via reactiveFileReader. Just pass your favorite xlsx-reading function as readFunc and specify an interval. reactiveFileReader will return a reactive expression that provides you with the contents of the file, and automatically invalidates when the file changes on disk.