JAVA-2331: Use minimum eviction time if set too low

Author: olim7t

core/src/main/java/com/datastax/oss/driver/internal/core/metrics/DropwizardMetricsFactory.java

@@ -48,7 +48,6 @@ public class DropwizardMetricsFactory implements MetricsFactory {
 
   private static final Logger LOG = LoggerFactory.getLogger(DropwizardMetricsFactory.class);
   static final Duration LOWEST_ACCEPTABLE_EXPIRE_AFTER = Duration.ofMinutes(5);
-  static final Duration DEFAULT_EXPIRE_AFTER = Duration.ofHours(1);
 
   private final String logPrefix;
   private final InternalDriverContext context;
@@ -105,12 +104,11 @@ static Duration getAndValidateEvictionTime(DriverExecutionProfile config, String
 
     if (evictionTime.compareTo(LOWEST_ACCEPTABLE_EXPIRE_AFTER) < 0) {
       LOG.warn(
-          "[{}] Value too low for {}: {} (It should be higher than {}). Forcing to {} instead.",
+          "[{}] Value too low for {}: {}. Forcing to {} instead.",
           logPrefix,
           DefaultDriverOption.METRICS_NODE_EXPIRE_AFTER.getPath(),
           evictionTime,
-          LOWEST_ACCEPTABLE_EXPIRE_AFTER,
-          DEFAULT_EXPIRE_AFTER);
+          LOWEST_ACCEPTABLE_EXPIRE_AFTER);
     }
 
     return evictionTime;

core/src/main/resources/reference.conf

@@ -1613,12 +1613,16 @@ datastax-java-driver {
       }
 
       # The time after which the node level metrics will be evicted.
-      # The eviction will happen only if none of the enabled node-level
-      # metrics is updated for a given node for a given time.
-      # When this interval elapses, all metrics for the idle node are removed.
-      # If you set it to a value lower than 5 minutes, it will be forced to a default 1 hour.
       #
-      # Required: no (defaults to 1 hour)
+      # This is used to unregister stale metrics if a node leaves the cluster or gets a new address.
+      # The eviction will happen only if none of the enabled node-level metrics is updated for a
+      # given node for a given time. When this interval elapses, all metrics for the idle node are
+      # removed.
+      #
+      # The lowest allowed value is 5 minutes. If you try to set it lower, the driver will log a
+      # warning and use 5 minutes.
+      #
+      # Required: yes
       # Modifiable at runtime: no
       # Overridable in a profile: no
       expire-after = 1 hour

core/src/test/java/com/datastax/oss/driver/internal/core/metrics/DropwizardMetricsFactoryTest.java

@@ -15,7 +15,6 @@
  */
 package com.datastax.oss.driver.internal.core.metrics;
 
-import static com.datastax.oss.driver.internal.core.metrics.DropwizardMetricsFactory.DEFAULT_EXPIRE_AFTER;
 import static com.datastax.oss.driver.internal.core.metrics.DropwizardMetricsFactory.LOWEST_ACCEPTABLE_EXPIRE_AFTER;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.Mockito.mock;
@@ -58,12 +57,11 @@ public void should_log_warning_when_provided_eviction_time_setting_is_too_low()
     assertThat(logger.loggingEventCaptor.getValue().getFormattedMessage())
         .contains(
             String.format(
-                "[%s] Value too low for %s: %s (It should be higher than %s). Forcing to %s instead.",
+                "[%s] Value too low for %s: %s. Forcing to %s instead.",
                 LOG_PREFIX,
                 DefaultDriverOption.METRICS_NODE_EXPIRE_AFTER.getPath(),
                 expireAfter,
-                LOWEST_ACCEPTABLE_EXPIRE_AFTER,
-                DEFAULT_EXPIRE_AFTER));
+                LOWEST_ACCEPTABLE_EXPIRE_AFTER));
   }
 
   @Test