[Infra] Remove additional indexFields related functions (#189706)

Relates to #180690

## Summary

This PR is a follow-up to #189541
and removes additional functions related to the `indexFields` that are
no longer needed

## Testing

Check `metricIndicesExist` and `remoteClustersExist` in the request by
changing the settings (in the first video I use metricbeat and no oblt
cluster and in the second one I am connected to oblt cluster)



https://github.com/user-attachments/assets/59920479-5a42-4a6a-a66a-307ddfc48fd8



https://github.com/user-attachments/assets/ef04120c-6873-4b0c-813c-388147c2b741

x-pack/plugins/observability_solution/infra/common/source_configuration/source_configuration.ts

@@ -130,15 +130,6 @@ export interface InfraSourceConfiguration
 /**
  * Source status
  */
-const SourceStatusFieldRuntimeType = rt.type({
-  name: rt.string,
-  type: rt.string,
-  searchable: rt.boolean,
-  aggregatable: rt.boolean,
-  displayable: rt.boolean,
-});
-
-export type InfraSourceIndexField = rt.TypeOf<typeof SourceStatusFieldRuntimeType>;
 
 export const SourceStatusRuntimeType = rt.type({
   logIndicesExist: rt.boolean,

x-pack/plugins/observability_solution/infra/server/lib/infra_types.ts

@@ -18,13 +18,11 @@ import { SavedObjectsClientContract } from '@kbn/core-saved-objects-api-server';
 import { RulesServiceSetup } from '../services/rules';
 import { InfraConfig, InfraPluginStartServicesAccessor } from '../types';
 import { KibanaFramework } from './adapters/framework/kibana_framework_adapter';
-import { InfraFieldsDomain } from './domains/fields_domain';
 import { InfraMetricsDomain } from './domains/metrics_domain';
 import { InfraSources } from './sources';
 import { InfraSourceStatus } from './source_status';
 
 export interface InfraDomainLibs {
-  fields: InfraFieldsDomain;
   logEntries: ILogsSharedLogEntriesDomain;
   metrics: InfraMetricsDomain;
 }

x-pack/plugins/observability_solution/infra/server/plugin.ts

@@ -23,7 +23,6 @@ import { LOGS_FEATURE_ID, METRICS_FEATURE_ID } from '../common/constants';
 import { publicConfigKeys } from '../common/plugin_config_types';
 import { LOGS_FEATURE, METRICS_FEATURE } from './features';
 import { initInfraServer } from './infra_server';
-import { FrameworkFieldsAdapter } from './lib/adapters/fields/framework_fields_adapter';
 import { InfraServerPluginSetupDeps, InfraServerPluginStartDeps } from './lib/adapters/framework';
 import { KibanaFramework } from './lib/adapters/framework/kibana_framework_adapter';
 import { KibanaMetricsAdapter } from './lib/adapters/metrics/kibana_metrics_adapter';
@@ -33,7 +32,6 @@ import {
   LOGS_RULES_ALERT_CONTEXT,
   METRICS_RULES_ALERT_CONTEXT,
 } from './lib/alerting/register_rule_types';
-import { InfraFieldsDomain } from './lib/domains/fields_domain';
 import { InfraMetricsDomain } from './lib/domains/metrics_domain';
 import { InfraBackendLibs, InfraDomainLibs } from './lib/infra_types';
 import { infraSourceConfigurationSavedObjectType, InfraSources } from './lib/sources';
@@ -210,9 +208,6 @@ export class InfraServerPlugin
     // and make them available via the request context so we can do away with
     // the wrapper classes
     const domainLibs: InfraDomainLibs = {
-      fields: new InfraFieldsDomain(new FrameworkFieldsAdapter(framework), {
-        sources,
-      }),
       logEntries: plugins.logsShared.logEntries,
       metrics: new InfraMetricsDomain(new KibanaMetricsAdapter(framework)),
     };

x-pack/plugins/observability_solution/infra/server/routes/metrics_sources/index.ts

@@ -24,7 +24,7 @@ import {
   MetricsSourceStatus,
   partialMetricsSourceConfigurationReqPayloadRT,
 } from '../../../common/metrics_sources';
-import { InfraSource, InfraSourceIndexField } from '../../lib/sources';
+import { InfraSource } from '../../lib/sources';
 import { InfraPluginRequestHandlerContext } from '../../types';
 import { getInfraMetricsClient } from '../../lib/helpers/get_infra_metrics_client';
 
@@ -42,36 +42,24 @@ export const initMetricsSourceConfigurationRoutes = (libs: InfraBackendLibs) =>
     requestContext: InfraPluginRequestHandlerContext,
     sourceId: string
   ): Promise<MetricsSourceStatus> => {
-    const [metricIndicesExistSettled, indexFieldsSettled] = await Promise.allSettled([
-      libs.sourceStatus.hasMetricIndices(requestContext, sourceId),
-      libs.fields.getFields(requestContext, sourceId, 'METRICS'),
-    ]);
-
-    /**
-     * Extract values from promises settlements
-     */
-    const metricIndicesExist = isFulfilled<boolean>(metricIndicesExistSettled)
-      ? metricIndicesExistSettled.value
-      : defaultStatus.metricIndicesExist;
-    const remoteClustersExist = hasRemoteCluster<boolean | InfraSourceIndexField[]>(
-      indexFieldsSettled,
-      metricIndicesExistSettled
-    );
-
-    /**
-     * Report gracefully handled rejections
-     */
-    if (!isFulfilled<InfraSourceIndexField[]>(indexFieldsSettled)) {
-      logger.error(indexFieldsSettled.reason);
-    }
-    if (!isFulfilled<boolean>(metricIndicesExistSettled)) {
-      logger.error(metricIndicesExistSettled.reason);
-    }
+    try {
+      const hasMetricIndices = await libs.sourceStatus.hasMetricIndices(requestContext, sourceId);
+      return {
+        metricIndicesExist: hasMetricIndices,
+        remoteClustersExist: true,
+      };
+    } catch (err) {
+      logger.error(err);
+
+      if (err instanceof NoSuchRemoteClusterError) {
+        return defaultStatus;
+      }
 
-    return {
-      metricIndicesExist,
-      remoteClustersExist,
-    };
+      return {
+        metricIndicesExist: false,
+        remoteClustersExist: true,
+      };
+    }
   };
 
   framework.registerRoute(
@@ -283,12 +271,3 @@ export const initMetricsSourceConfigurationRoutes = (libs: InfraBackendLibs) =>
 const isFulfilled = <Type>(
   promiseSettlement: PromiseSettledResult<Type>
 ): promiseSettlement is PromiseFulfilledResult<Type> => promiseSettlement.status === 'fulfilled';
-
-const hasRemoteCluster = <Type>(...promiseSettlements: Array<PromiseSettledResult<Type>>) => {
-  const isRemoteMissing = promiseSettlements.some(
-    (settlement) =>
-      !isFulfilled<Type>(settlement) && settlement.reason instanceof NoSuchRemoteClusterError
-  );
-
-  return !isRemoteMissing;
-};