[DNS caching] Use duration as setting (#185923)

packages/core/elasticsearch/core-elasticsearch-client-server-internal/src/agent_manager.ts

@@ -60,6 +60,9 @@ export class AgentManager implements AgentFactoryProvider, AgentStatsProvider {
     this.agents = new Set();
     // Use DNS caching to avoid too many repetitive (and CPU-blocking) dns.lookup calls
     if (options.dnsCacheTtlInSeconds > 0) {
+      this.logger.info(
+        `Caching ES host DNS resolutions for up to ${options.dnsCacheTtlInSeconds}s. If this causes problems, change the setting "elasticsearch.dnsCacheTtl: ${options.dnsCacheTtlInSeconds}s".`
+      );
       this.cacheableLookup = new CacheableLookup({
         maxTtl: options.dnsCacheTtlInSeconds,
       });

packages/core/elasticsearch/core-elasticsearch-client-server-internal/src/client_config.test.ts

@@ -25,7 +25,7 @@ const createConfig = (
     sniffInterval: false,
     requestHeadersWhitelist: ['authorization'],
     hosts: ['http://localhost:80'],
-    dnsCacheTtlInSeconds: 0,
+    dnsCacheTtl: duration(0, 'seconds'),
     ...parts,
   };
 };

packages/core/elasticsearch/core-elasticsearch-client-server-internal/src/cluster_client.test.ts

@@ -34,7 +34,7 @@ const createConfig = (
     requestHeadersWhitelist: ['authorization'],
     customHeaders: {},
     hosts: ['http://localhost'],
-    dnsCacheTtlInSeconds: 0,
+    dnsCacheTtl: duration(0, 'seconds'),
     ...parts,
   };
 };

packages/core/elasticsearch/core-elasticsearch-server-internal/src/elasticsearch_config.test.ts

@@ -33,7 +33,7 @@ test('set correct defaults', () => {
       "apisToRedactInLogs": Array [],
       "compression": false,
       "customHeaders": Object {},
-      "dnsCacheTtlInSeconds": 0,
+      "dnsCacheTtl": "P0D",
       "healthCheckDelay": "PT2.5S",
       "healthCheckStartupDelay": "PT0.5S",
       "hosts": Array [

packages/core/elasticsearch/core-elasticsearch-server-internal/src/elasticsearch_config.ts

@@ -186,7 +186,7 @@ export const configSchema = schema.object({
     }),
     { defaultValue: [] }
   ),
-  dnsCacheTtlInSeconds: schema.number({ defaultValue: 0, min: 0, max: Infinity }),
+  dnsCacheTtl: schema.duration({ defaultValue: 0, min: 0 }),
 });
 
 const deprecations: ConfigDeprecationProvider = () => [
@@ -429,10 +429,10 @@ export class ElasticsearchConfig implements IElasticsearchConfig {
   public readonly apisToRedactInLogs: ElasticsearchApiToRedactInLogs[];
 
   /**
-   * The maximum number of seconds to retain the DNS lookup resolutions.
+   * The maximum time to retain the DNS lookup resolutions.
    * Set to 0 to disable the cache (default Node.js behavior)
    */
-  public readonly dnsCacheTtlInSeconds: number;
+  public readonly dnsCacheTtl: Duration;
 
   constructor(rawConfig: ElasticsearchConfigType) {
     this.ignoreVersionMismatch = rawConfig.ignoreVersionMismatch;
@@ -459,7 +459,7 @@ export class ElasticsearchConfig implements IElasticsearchConfig {
     this.compression = rawConfig.compression;
     this.skipStartupConnectionCheck = rawConfig.skipStartupConnectionCheck;
     this.apisToRedactInLogs = rawConfig.apisToRedactInLogs;
-    this.dnsCacheTtlInSeconds = rawConfig.dnsCacheTtlInSeconds;
+    this.dnsCacheTtl = rawConfig.dnsCacheTtl;
 
     const { alwaysPresentCertificate, verificationMode } = rawConfig.ssl;
     const { key, keyPassphrase, certificate, certificateAuthorities } = readKeyAndCerts(rawConfig);

packages/core/elasticsearch/core-elasticsearch-server-internal/src/elasticsearch_service.ts

@@ -224,9 +224,11 @@ export class ElasticsearchService
     });
   }
 
-  private getAgentManager({ dnsCacheTtlInSeconds }: ElasticsearchClientConfig): AgentManager {
+  private getAgentManager({ dnsCacheTtl }: ElasticsearchClientConfig): AgentManager {
     if (!this.agentManager) {
-      this.agentManager = new AgentManager(this.log.get('agent-manager'), { dnsCacheTtlInSeconds });
+      this.agentManager = new AgentManager(this.log.get('agent-manager'), {
+        dnsCacheTtlInSeconds: dnsCacheTtl?.asSeconds() ?? 0, // it should always exists, but some test shortcuts and mocks break this assumption
+      });
     }
     return this.agentManager;
   }

packages/core/elasticsearch/core-elasticsearch-server/src/client/client_config.ts

@@ -50,7 +50,7 @@ export interface ElasticsearchClientConfig {
   caFingerprint?: string;
   ssl?: ElasticsearchClientSslConfig;
   apisToRedactInLogs?: ElasticsearchApiToRedactInLogs[];
-  dnsCacheTtlInSeconds: number;
+  dnsCacheTtl: Duration;
 }
 
 /**

packages/core/elasticsearch/core-elasticsearch-server/src/elasticsearch_config.ts

@@ -151,10 +151,10 @@ export interface IElasticsearchConfig {
   readonly apisToRedactInLogs: ElasticsearchApiToRedactInLogs[];
 
   /**
-   * The maximum number of seconds to retain the DNS lookup resolutions.
+   * The maximum time to retain the DNS lookup resolutions.
    * Set to 0 to disable the cache (default Node.js behavior)
    */
-  readonly dnsCacheTtlInSeconds: number;
+  readonly dnsCacheTtl: Duration;
 }
 
 /**

packages/core/test-helpers/core-test-helpers-model-versions/src/test_bed/test_kit.ts

@@ -203,7 +203,7 @@ const getElasticsearchClient = async (
     type: 'data',
     agentFactoryProvider: new AgentManager(
       loggerFactory.get('elasticsearch-service', 'agent-manager'),
-      { dnsCacheTtlInSeconds: 0 }
+      { dnsCacheTtlInSeconds: esClientConfig.dnsCacheTtl?.asSeconds() ?? 0 }
     ),
     kibanaVersion,
   });

src/cli_setup/utils.ts

@@ -50,7 +50,7 @@ export const elasticsearch = new ElasticsearchService(logger, kibanaPackageJson.
         type,
         // we use an independent AgentManager for cli_setup, no need to track performance of this one
         agentFactoryProvider: new AgentManager(logger.get('agent-manager'), {
-          dnsCacheTtlInSeconds: 0,
+          dnsCacheTtlInSeconds: config?.dnsCacheTtl?.asSeconds() ?? 0,
         }),
         kibanaVersion: kibanaPackageJson.version,
       });

src/core/server/integration_tests/saved_objects/migrations/kibana_migrator_test_kit.ts

@@ -267,7 +267,7 @@ const getElasticsearchClient = async (
     type: 'data',
     agentFactoryProvider: new AgentManager(
       loggerFactory.get('elasticsearch-service', 'agent-manager'),
-      { dnsCacheTtlInSeconds: 0 }
+      { dnsCacheTtlInSeconds: esClientConfig.dnsCacheTtl?.asSeconds() ?? 0 }
     ),
     kibanaVersion,
   });

x-pack/plugins/monitoring/server/config.test.ts

@@ -59,7 +59,7 @@ describe('config schema', () => {
             "apisToRedactInLogs": Array [],
             "compression": false,
             "customHeaders": Object {},
-            "dnsCacheTtlInSeconds": 0,
+            "dnsCacheTtl": "P0D",
             "healthCheck": Object {
               "delay": "PT2.5S",
               "startupDelay": "PT0.5S",