Langium-Sprotty exemples on the git?

[Olivier-D09]

hi, I'm looking for examples of Langium representation using sprotty, I've searched on the git and haven't found any, does anyone know where I can find some, if any on github?

[spoenemann]

The sprotty-vscode integration has such an example: https://github.com/eclipse-sprotty/sprotty-vscode/tree/master/examples

[jdeantoni]

Hi, thanks for the link. Having the same question I had a look at the sprotty example and I saw that the sprotty code is "rebundling" the LSP.

Is there a way to add a sprotty representation to a langium language without modifying/rebundling the orginal LSP ?

[spoenemann]

No, because the LSP doesn't have any representation of AST contents. You need some way to transform the AST into a diagram model. The easiest way is to do it within the language server, but an alternative could be to transfer the AST to the client using JsonSerializer.

[jdeantoni]

I see. I'll give a try to both !
Thanks for the answer !

[spoenemann]

Here's an example of how that can work:

langium/examples/statemachine/src/language-server/main-browser.ts

Lines 25 to 38 in f6889f2

	// Send a notification with the serialized AST after every document change
	type DocumentChange = { uri: string, content: string, diagnostics: Diagnostic[] };
	const documentChangeNotification = new NotificationType<DocumentChange>('browser/DocumentChange');
	const jsonSerializer = statemachine.serializer.JsonSerializer;
	shared.workspace.DocumentBuilder.onBuildPhase(DocumentState.Validated, documents => {
	for (const document of documents) {
	const json = jsonSerializer.serialize(document.parseResult.value);
	connection.sendNotification(documentChangeNotification, {
	uri: document.uri.toString(),
	content: json,
	diagnostics: document.diagnostics ?? []
	});
	}
	});

[jdeantoni]

Thanks ! That surely helps !