Demo application for Domino JNA Views to play with
Karsten Lehmann 18 July 2024 17:50:24
Today I attended the "Developer Variety Hour" webinar of OpenNTF and did a demo of the new Virtual View API of Domino JNA.I built a small web application that combines a Sunburst diagram (taken from the D3 website, enhanced by a training session with Anthropics Claude AI chat :-) ) with a categorized view, built on top of a Bootstrap 5 table.
The application looks like this:
and it's available for you to play with here: https://www.mindoo.de/test/jnavirtualviews.nsf/sunburst.xsp
Both components fetch their data from an XAgent style XPage where a Virtual View is used to read document information from two fakenames databases:
public Optional< VirtualView > getViewById(String id) {
VirtualView view = null;
if ("fakenames_bycontinent_categorized".equals(id)) {
view = VirtualViewFactory.INSTANCE.createViewOnce(id,
17, // view version number
10, TimeUnit.MINUTES, // keep in memory for 10 minutes
(viewId) -> {
return VirtualViewFactory.createView(
// use a Java function to compute the "Continent" category:
new VirtualViewColumn("Continent", "$1", Category.YES, Hidden.NO, ColumnSort.ASCENDING, Total.NONE,
new VirtualViewColumnValueFunction< String >(1) {
@Override
public String getValue(String origin, String itemName,
INoteSummary columnValues) {
String companyName = columnValues.getAsString("CompanyName", "");
Map
return lookupMap.getOrDefault(companyName, "Unknown");
}
}),
// use formula language for the remaining columns:
new VirtualViewColumn("Company Name", "$2", Category.YES, Hidden.NO,
ColumnSort.ASCENDING, Total.NONE,
"@Left(CompanyName;1) + \"\\\\\" + CompanyName"),
new VirtualViewColumn("Lastname", "Lastname", Category.NO, Hidden.NO,
ColumnSort.ASCENDING, Total.NONE,
"Lastname"),
new VirtualViewColumn("Firstname", "Firstname", Category.NO, Hidden.NO,
ColumnSort.ASCENDING, Total.NONE,
"Firstname"),
new VirtualViewColumn("CompanyName", "CompanyName", Category.NO,
Hidden.YES, ColumnSort.NONE, Total.NONE,
"CompanyName")
)
// load data from two fakenames databases
.withDbSearch("fakenames1", "", "fakenames.nsf", "Form=\"Person\"")
.withDbSearch("fakenames2", "", "fakenames2.nsf", "Form=\"Person\"")
.build();
});
}
return Optional.ofNullable(view);
}
Initial index generation for about 40.000 fakenames docs takes 5 seconds on our server. The view is set to expire after 10 minutes and will be automatically be rebuilr.
The first column value is computed via Java code and looks up the continent for the company name of a fakenames person (let's call it a JOIN operation).
Since all data access is done in-memory (no legacy Domino view is required), REST API response times are ultra-fast and take 50ms for each request. Part of those 50ms is opening the two fakenames database and checking if anything relevant has been changed/added/deleted. As presented in the webinar, changing DB documents is immediately reflected in the web app.
Building this demo app this week I discovered a few issues in the Virtual View API of Domino JNA 0.9.52 especially when processing NSF changes (the code produced duplicate rows).
I will publish a new Domino JNA version this week with fixes.
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