[Fleet] Add fleet server telemetry

x-pack/plugins/fleet/server/collectors/agent_collectors.ts

@@ -5,8 +5,7 @@
  * 2.0.
  */
 
-import type { SavedObjectsClient } from 'kibana/server';
-import type { ElasticsearchClient } from 'kibana/server';
+import type { SavedObjectsClient, ElasticsearchClient } from 'kibana/server';
 
 import type { FleetConfigType } from '../../common/types';
 import * as AgentService from '../services/agents';

x-pack/plugins/fleet/server/collectors/fleet_server_collector.ts

@@ -0,0 +1,73 @@
+/*
+ * 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 type { SavedObjectsClient, ElasticsearchClient } from 'kibana/server';
+
+import { packagePolicyService, settingsService } from '../services';
+import { getAgentStatusForAgentPolicy } from '../services/agents';
+import { isFleetServerSetup } from '../services/fleet_server';
+
+const DEFAULT_USAGE = {
+  total_all_statuses: 0,
+  healthy: 0,
+  num_host_urls: 0,
+};
+
+export interface FleetServerUsage {
+  healthy: number;
+  total_all_statuses: number;
+  num_host_urls: number;
+}
+
+export const getFleetServerUsage = async (
+  soClient?: SavedObjectsClient,
+  esClient?: ElasticsearchClient
+): Promise<any> => {
+  if (!soClient || !esClient || !(await isFleetServerSetup())) {
+    return DEFAULT_USAGE;
+  }
+
+  const numHostsUrls =
+    (await settingsService.getSettings(soClient)).fleet_server_hosts?.length ?? 0;
+
+  // Find all policies with Fleet server than query agent status
+
+  let hasMore = true;
+  const policyIds = new Set<string>();
+  let page = 1;
+  while (hasMore) {
+    const res = await packagePolicyService.list(soClient, {
+      page: page++,
+      perPage: 20,
+      kuery: 'ingest-package-policies.package.name:fleet-server',
+    });
+
+    for (const item of res.items) {
+      policyIds.add(item.policy_id);
+    }
+
+    if (res.items.length === 0) {
+      hasMore = false;
+    }
+  }
+
+  if (policyIds.size === 0) {
+    return DEFAULT_USAGE;
+  }
+
+  const { total, inactive, online } = await getAgentStatusForAgentPolicy(
+    soClient,
+    esClient,
+    undefined,
+    [...policyIds].map((policyId) => `(policy_id:"${policyId}")`).join(' or ')
+  );
+
+  return {
+    total_all_statuses: total + inactive,
+    healthy: online,
+    num_host_urls: numHostsUrls,
+  };
+};

x-pack/plugins/fleet/server/collectors/register.ts

@@ -16,11 +16,14 @@ import type { AgentUsage } from './agent_collectors';
 import { getInternalClients } from './helpers';
 import { getPackageUsage } from './package_collectors';
 import type { PackageUsage } from './package_collectors';
+import { getFleetServerUsage } from './fleet_server_collector';
+import type { FleetServerUsage } from './fleet_server_collector';
 
 interface Usage {
   agents_enabled: boolean;
   agents: AgentUsage;
   packages: PackageUsage[];
+  fleet_server: FleetServerUsage;
 }
 
 export function registerFleetUsageCollector(
@@ -43,6 +46,7 @@ export function registerFleetUsageCollector(
       return {
         agents_enabled: getIsAgentsEnabled(config),
         agents: await getAgentUsage(config, soClient, esClient),
+        fleet_server: await getFleetServerUsage(soClient, esClient),
         packages: await getPackageUsage(soClient),
       };
     },
@@ -80,6 +84,27 @@ export function registerFleetUsageCollector(
           },
         },
       },
+      fleet_server: {
+        total_all_statuses: {
+          type: 'long',
+          _meta: {
+            description:
+              'The total number of Fleet Server agents in any state, both enrolled and inactive.',
+          },
+        },
+        healthy: {
+          type: 'long',
+          _meta: {
+            description: 'The total number of enrolled Fleet Server agents in a healthy state.',
+          },
+        },
+        num_host_urls: {
+          type: 'long',
+          _meta: {
+            description: 'The number of Fleet Server hosts configured in Fleet settings.',
+          },
+        },
+      },
       packages: {
         type: 'array',
         items: {