Unknown visualization type breaks listing page

[flash1293]

Kibana version: 7.8 - master

Describe the bug: In a space with "visualize:enableLabs" disabled in advanced settings, if there is a visualization saved object which can't be mapped to an existing type in the visualization registry, the visualization listing page does not render.

Steps to reproduce:

1. Disable "visualize:enableLabs" in advanced settings
2. Create visualization
3. Go to saved object management and change "type" in "visState" to something else (like "thisvistypedoesnotexist")
4. Go to Visualize listing page
5. Error is shown

Expected behavior:
Visualizations should still be shown with the corrupted one being un-editable.

Any additional context:
In

kibana/src/plugins/visualize/public/application/components/visualize_listing.tsx

Lines 100 to 111 in 19bda1f

	const fetchItems = useCallback(
	(filter) => {
	const isLabsEnabled = uiSettings.get(VISUALIZE_ENABLE_LABS_SETTING);
	return savedVisualizations
	.findListItems(filter, listingLimit)
	.then(({ total, hits }: { total: number; hits: object[] }) => ({
	total,
	hits: hits.filter((result: any) => isLabsEnabled || result.type.stage !== 'experimental'),
	}));
	},
	[listingLimit, savedVisualizations, uiSettings]
	);

, the type is accessed without type guard.

The code mapping results from saved object client however leaves it as undefined if the type can't be found in the registry:

kibana/src/plugins/visualizations/public/saved_visualizations/saved_visualizations.ts

Line 47 in bb174fd

source.error = 'Unknown visualization type';

An easy solution would be to declare type as optional and check for existence before accessing it.

A workaround is to enable "visualize:enableLabs"

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[stratoula]

@flash1293 I also get this

when I have at least one Lens visualization. It has to do with the fact that we search for result.type.stage while on Lens is on the upper level result.stage.

[flash1293]

@stratoula Welp, great point, I didn't realize. This definitely raises priority 🙂