[Uptime] Uptime index config using kibana.yml (#115775)

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>

src/dev/build/tasks/os_packages/docker_generator/resources/base/bin/kibana-docker

@@ -375,6 +375,7 @@ kibana_vars=(
     xpack.task_manager.poll_interval
     xpack.task_manager.request_capacity
     xpack.task_manager.version_conflict_threshold
+    xpack.uptime.index
 )
 
 longopts=''

x-pack/plugins/uptime/server/config.ts

@@ -0,0 +1,19 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { PluginConfigDescriptor } from 'kibana/server';
+import { schema, TypeOf } from '@kbn/config-schema';
+
+export const config: PluginConfigDescriptor = {
+  schema: schema.maybe(
+    schema.object({
+      index: schema.string(),
+    })
+  ),
+};
+
+export type UptimeConfig = TypeOf<typeof config.schema>;

x-pack/plugins/uptime/server/index.ts

@@ -10,3 +10,5 @@ import { Plugin } from './plugin';
 
 export const plugin = (initializerContext: PluginInitializerContext) =>
   new Plugin(initializerContext);
+
+export { config } from './config';

x-pack/plugins/uptime/server/lib/saved_objects.ts

@@ -10,8 +10,10 @@ import { DYNAMIC_SETTINGS_DEFAULTS } from '../../common/constants';
 import { DynamicSettings } from '../../common/runtime_types';
 import { SavedObjectsType, SavedObjectsErrorHelpers } from '../../../../../src/core/server';
 import { UMSavedObjectsQueryFn } from './adapters';
+import { UptimeConfig } from '../config';
 
 export interface UMSavedObjectsAdapter {
+  config: UptimeConfig;
   getUptimeDynamicSettings: UMSavedObjectsQueryFn<DynamicSettings>;
   setUptimeDynamicSettings: UMSavedObjectsQueryFn<void, DynamicSettings>;
 }
@@ -55,12 +57,17 @@ export const umDynamicSettings: SavedObjectsType = {
 };
 
 export const savedObjectsAdapter: UMSavedObjectsAdapter = {
+  config: null,
   getUptimeDynamicSettings: async (client): Promise<DynamicSettings> => {
     try {
       const obj = await client.get<DynamicSettings>(umDynamicSettings.name, settingsObjectId);
       return obj?.attributes ?? DYNAMIC_SETTINGS_DEFAULTS;
     } catch (getErr) {
+      const config = savedObjectsAdapter.config;
       if (SavedObjectsErrorHelpers.isNotFoundError(getErr)) {
+        if (config?.index) {
+          return { ...DYNAMIC_SETTINGS_DEFAULTS, heartbeatIndices: config.index };
+        }
         return DYNAMIC_SETTINGS_DEFAULTS;
       }
       throw getErr;

x-pack/plugins/uptime/server/plugin.ts

@@ -16,9 +16,10 @@ import {
 import { uptimeRuleFieldMap } from '../common/rules/uptime_rule_field_map';
 import { initServerWithKibana } from './kibana.index';
 import { KibanaTelemetryAdapter, UptimeCorePlugins } from './lib/adapters';
-import { umDynamicSettings } from './lib/saved_objects';
+import { savedObjectsAdapter, umDynamicSettings } from './lib/saved_objects';
 import { mappingFromFieldMap } from '../../rule_registry/common/mapping_from_field_map';
 import { Dataset } from '../../rule_registry/server';
+import { UptimeConfig } from './config';
 
 export type UptimeRuleRegistry = ReturnType<Plugin['setup']>['ruleRegistry'];
 
@@ -32,6 +33,10 @@ export class Plugin implements PluginType {
   }
 
   public setup(core: CoreSetup, plugins: UptimeCorePlugins) {
+    const config = this.initContext.config.get<UptimeConfig>();
+
+    savedObjectsAdapter.config = config;
+
     this.logger = this.initContext.logger.get();
     const { ruleDataService } = plugins.ruleRegistry;