Update on AG Grid data viewer, and use infinite row model for dynamic data loading

[Fred-Wu]

What problem did you solve?

1. Fixed the issue that multiple data viewer would open by calling View() for the same data. The fix introduced dataview_uuid, and check whether the same window has been opened or not. It will create a window if it has been closed, but refresh the window if it has been opened already.

2. Changed the AG Grid data viewer to infinite row model, which allows dynamic data loading, even for very large data. The changes include

   • implementation of server side data fetching, sorting and filtering by sending requests to an R session. The change was made to showDataView under /src/session.ts;
   • update of dataview_table() in /R/session/vsc.R to manage the request for sorting and filtering based on AG Grid options and data types, such as number (numeric), text (character), date (Date), boolean (logical);
   • setting cache block size at 100 when scrolling down the data viewer;
   • making R's data.table a required package to be installed.;
   • removal of pagination setting in AG Grid, but not yet from vscode-R setting;
   • data viewer UI updates
     - row Id column (row) now shows row number from 1 to N even after sorting and filtering. The header name (row) was replaced by (# filtered rows) / (# total rows)
     - Boolean column initially showed as "true/false" has been changed to "TRUE/FALSE". This is treated as a numeric column, and only Equals option is enabled, with hint to use 1 for TRUE, and 0 for FALSE when apply a filter on this column.
     - filtering pane is now below header name so that one could see what have been filtered with what values.

Would love to hear your feedbacks on this and whether this change would be something you consider to incorporate.

(If you have)Screenshot

demo1.mp4

2. with n = 1e7

demo2_small.mp4

3. with n = 1e8

demo3_small.mp4

[Fred-Wu]

1. Data loading has been improved with a cached version for data fetching, sorting and filtering in the data viewer.
2. A data viewer would be rebuilt if View() is called again. Otherwise, it may not reflect in-memory changes if data is updated using data.table package.
3. Both data name and an expression in View() is allowed, with maximum 500 width cut off.

[Fred-Wu]

• To fix errors in checks
• To allow POSIXct date/time filed as date in the data viewer
• To remove pagination and row limit from extension options.

[Fred-Wu]

I think I have made all the changes I want. Would like someone interested in this to take a look, and provide feedback on errors I missed.