Remove legacy plugin discovery

[joshdover]

Related to #56205

Once all 1st party legacy plugins have been removed or migrated, we should disable legacy plugin discovery altogether, even for 3rd party plugins.

When we make this change, we also need to add a note to the "breaking changes" doc for 7.10

Blockers by team

@elastic/stack-monitoring-ui

• Migrate /api/settings route to Kibana platform #76416

@elastic/kibana-app-arch

• Replace usage of /elasticsearch/_msearch endpoint in Index Pattern Management UI #73993

@elastic/kibana-core-ui

• Replace usage of /elasticsearch/_msearch endpoint in tutorials #73992

@elastic/es-ui

• [Console] Legacy Config Deprecations in 7.10 #68497

@elastic/logs-metrics-ui

• [Logs App] Use new getActiveSpace function, abandon getInjectedVar() #68142

@elastic/kibana-gis

• Migrate legacy map UI settings #74562

@elastic/kibana-security

• remove legacy security plugin #75648 (blocked by Migrate status service and status page to New Platform #41983)
• Remove legacy spaces plugin #74532 (blocked by Migrate status service and status page to New Platform #41983)

@elastic/kibana-platform

• Migrate uiSettings defintions to NP #59755
• Beats Management plugin: migrate server-side code #70930
• Migrate ui/styles to New Platform #58369
• Migrate status service and status page to New Platform #41983
• Migrate CSP usage collector to New Platform #50511
• Migrate data folder creation to core #73002

[elasticmachine]

Pinging @elastic/kibana-platform (Team:Platform)

[pgayvallet]

We are very close to being able to remove the legacy optimizer, however we still got some work to do before we will be able to totally drop legacy plugin discovery, as there are some remaining.

oss

apm-oss

Done in #73016

console_legacy

This is used to expose elasticsearchUrl to the ui

kibana/src/legacy/core_plugins/console_legacy/index.ts

Lines 35 to 46 in 6c62c68

	async init(server: any) {
	_legacyEsConfig = await server.newPlatform.__internals.elasticsearch.legacy.config$
	.pipe(first())
	.toPromise();
	},
	uiExports: {
	injectDefaultVars: () => ({
	elasticsearchUrl: url.format(
	Object.assign(url.parse(head(_legacyEsConfig.hosts) as any), { auth: false })
	),
	}),

I thought it could be done by exposing an endpoint that would access elasticsearch.legacy.config$, but I was wrong, as this property is only exposed on the internal / legacy contract. I moved #68497 back to 7.10, this removal is blocked by it.

cc @elastic/es-ui

elasticsearch

It's exposing things like createCluster and getCluster, which may be removed if no more legacy plugins are using them (did not check usages in the legacy server code itself), but it's also exposing waitUntilReady which is tightly coupled with the legacy server itself. I guess this plugin will have to stay until the end of legacy.

EDIT: it seems it is also registering proxy routes to ES

kibana/src/legacy/core_plugins/elasticsearch/server/lib/create_proxy.js

Lines 26 to 33 in bf04235

	server.route({
	method: 'POST',
	path: '/elasticsearch/_msearch',
	config: {
	payload: {
	parse: 'gunzip',
	},
	},

Not sure who is consuming these, does anyone have an idea?

kibana

Still doing a few things:

• Exporting the src/legacy/core_plugins/kibana/public/index.scss as styleSheetPaths. This seems closely related to Migrate ui/styles to New Platform #58369

• Exporting some uiSettingDefaults

kibana/src/legacy/core_plugins/kibana/index.js

Lines 42 to 45 in d1a6fa2

	uiExports: {
	styleSheetPaths: resolve(__dirname, 'public/index.scss'),
	uiSettingDefaults: getUiSettingDefaults(),
	},

Not sure if related to #22779 or #59755

• Registering the csp usage collector

kibana/src/legacy/core_plugins/kibana/index.js

Lines 59 to 62 in d1a6fa2

	init: async function (server) {
	const { usageCollection } = server.newPlatform.setup.plugins;
	registerCspCollector(usageCollection, server);
	},

Not sure I saw this one listed anywhere. csp config is now in core, so I guess this should probably be moved there, but we need a way to access usageCollection plugin from within core. Seems related to #56762 (comment)

• create the data folder

created #73002

status_page

Done in #72017.

The empty app plugin left should safely be removed once the legacy optimizer is no more.

tests_bundle

I have no idea what this is for. I see some karma references, is this only used for karma testing @elastic/kibana-operations?

x-pack

beats_management

Covered by #70930

Monitoring

Used to bridge the legacy status API to the KP plugin

kibana/x-pack/legacy/plugins/monitoring/index.ts

Lines 21 to 34 in 06b1820

	init(server: Hapi.Server) {
	const npMonitoring = server.newPlatform.setup.plugins.monitoring as object & {
	registerLegacyAPI: (api: unknown) => void;
	};
	if (npMonitoring) {
	const kbnServerStatus = this.kbnServer.status;
	npMonitoring.registerLegacyAPI({
	getServerStatus: () => {
	const status = kbnServerStatus.toJSON();
	return status?.overall?.state;
	},
	});
	}
	},

Depends on #41983

security

Only here to expose some hacks (x-pack/legacy/plugins/security/public/hacks/legacy.ts) for the legacy apps. Should be good to remove as we no longer have any legacy apps? Or is this still used for management tabs @elastic/kibana-security

spaces

• Used to register some redirection routes

kibana/x-pack/legacy/plugins/spaces/public/legacy.ts

Lines 8 to 18 in 7ab38ff

	import routes from 'ui/routes';
	import { SpacesPluginSetup } from '../../../../plugins/spaces/public';
	const spaces = (npSetup.plugins as any).spaces as SpacesPluginSetup;
	if (spaces) {
	routes.when('/management/spaces/list', { redirectTo: '/management/kibana/spaces' });
	routes.when('/management/spaces/create', { redirectTo: '/management/kibana/spaces/create' });
	routes.when('/management/spaces/edit/:spaceId', {
	redirectTo: '/management/kibana/spaces/edit/:spaceId',
	});
	}

Not sure if these are still really used now that we don't have any app running in legacy mode? @elastic/kibana-security

• expose the replaceInjectedVars in uiExports.

Seems to be used to add the activeSpace var. Not sure if this is still relevant @elastic/kibana-security?

• expose things such as getSpaceId and getActiveSpace on the server

This seems fine to remove once we no longer have any other xpack server-side legacy plugin.

xpack_main

This one is doing quite a few things. I guess this will be the last xpack plugin to be removed.

[sorenlouv]

@elastic/apm-ui Is this still used anywhere, or can the legacy apm_oss plugin be removed?

apm_oss is a dependency of xpack.apm so cannot be removed now or in the future. However, looking closer I see there are two apm_oss plugins:

• https://github.com/elastic/kibana/tree/master/src/plugins/apm_oss
• https://github.com/elastic/kibana/tree/master/src/legacy/core_plugins/apm_oss

I think that legacy/core_plugins/apm_oss can be merged into plugins/apm_oss.

From what I see, the remains are only used to expose indexPatterns to the server

I'm not sure if server.expose is still used for anything. it was added by @tylersmalley in #29845 so maybe he knows.

[pgayvallet]

apm_oss is a dependency of xpack.apm so cannot be removed now or in the future. However, looking closer I see there are two apm_oss plugins:

Yea, we are only talking about legacy removal here (src/legacy/core_plugins/apm_oss)

[mshustov]

Exporting some uiSettingDefaults

That's #59755 and #63459 not sure it's a real blocker. we can register them manually

[azasypkin]

Security
Only here to expose some hacks (x-pack/legacy/plugins/security/public/hacks/legacy.ts) for the legacy apps. Should be good to remove as we no longer have any legacy apps? Or is this still used for management tabs @elastic/kibana-security

Once we don't have any Angular based plugins then we can get rid of this completely. Maintaining /account ---> /security/account redirect isn't critical.

Spaces
Used to register some redirection routes
Not sure if these are still really used now that we don't have any app running in legacy mode? @elastic/kibana-security

Since these redirects don't seem to work right now anyway (likely because Management plugin migrated away from ui/routes, I think it's reasonable to drop legacy links (@legrego can keep me honest here).

expose the replaceInjectedVars in uiExports.
Seems to be used to add the activeSpace var. Not sure if this is still relevant @elastic/kibana-security?

It seems Infra is still using this. I believe they can switch to the contract Spaces KP plugins exposes now.

expose things such as getSpaceId and getActiveSpace on the server
This seems fine to remove once we no longer have any other xpack server-side legacy plugin.

Sounds good to me.

[pgayvallet]

It seems Infra is still using this. I believe they can switch to the contract Spaces KP plugins exposes now.

@elastic/logs-metrics-ui do you have an issue to replace these space injectedVars with the spaces plugin API?

[tylersmalley]

tests_bundle

I have no idea what this is for. I see some karma references, is this only used for karma testing @elastic/kibana-operations?

That's my understanding. @spalger is there anything else this is used for? Can we remove once all Karma test are removed (related: #71002)?

[spalger]

Yeah, this will go along with karma and the legacy optimizer

[cjcenizal]

elasticsearch

@pgayvallet It looks like https://github.com/elastic/kibana/blob/master/src/plugins/home/public/application/components/tutorial/tutorial.js#L206 makes a request to /elasticsearch/_msearch.

[weltenwort]

@elastic/logs-metrics-ui do you have an issue to replace these space injectedVars with the spaces plugin API?

Yes, we track it in #68142