com.zaxxer.hikari.metrics.dropwizard.CodahaleHealthChecker Maven / Gradle / Ivy
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/*
* Copyright (C) 2014 Brett Wooldridge
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.zaxxer.hikari.metrics.dropwizard;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;
import java.util.SortedMap;
import java.util.concurrent.TimeUnit;
import com.codahale.metrics.Metric;
import com.codahale.metrics.MetricFilter;
import com.codahale.metrics.MetricRegistry;
import com.codahale.metrics.Timer;
import com.codahale.metrics.health.HealthCheck;
import com.codahale.metrics.health.HealthCheckRegistry;
import com.zaxxer.hikari.HikariConfig;
import com.zaxxer.hikari.pool.HikariPool;
/**
* Provides Dropwizard HealthChecks. Two health checks are provided:
*
* - ConnectivityCheck
* - Connection99Percent
*
* The ConnectivityCheck will use the connectionTimeout
, unless the health check property
* connectivityCheckTimeoutMs
is defined. However, if either the connectionTimeout
* or the connectivityCheckTimeoutMs
is 0 (infinite), a timeout of 10 seconds will be used.
*
* The Connection99Percent health check will only be registered if the health check property
* expected99thPercentileMs
is defined and greater than 0.
*
* @author Brett Wooldridge
*/
public final class CodahaleHealthChecker
{
/**
* Register Dropwizard health checks.
*
* @param pool the pool to register health checks for
* @param hikariConfig the pool configuration
* @param registry the HealthCheckRegistry into which checks will be registered
*/
public static void registerHealthChecks(final HikariPool pool, final HikariConfig hikariConfig, final HealthCheckRegistry registry)
{
final Properties healthCheckProperties = hikariConfig.getHealthCheckProperties();
final MetricRegistry metricRegistry = (MetricRegistry) hikariConfig.getMetricRegistry();
final long checkTimeoutMs = Long.parseLong(healthCheckProperties.getProperty("connectivityCheckTimeoutMs", String.valueOf(hikariConfig.getConnectionTimeout())));
registry.register(MetricRegistry.name(hikariConfig.getPoolName(), "pool", "ConnectivityCheck"), new ConnectivityHealthCheck(pool, checkTimeoutMs));
final long expected99thPercentile = Long.parseLong(healthCheckProperties.getProperty("expected99thPercentileMs", "0"));
if (metricRegistry != null && expected99thPercentile > 0) {
SortedMap timers = metricRegistry.getTimers(new MetricFilter() {
@Override
public boolean matches(String name, Metric metric)
{
return name.equals(MetricRegistry.name(hikariConfig.getPoolName(), "pool", "Wait"));
}
});
if (!timers.isEmpty()) {
final Timer timer = timers.entrySet().iterator().next().getValue();
registry.register(MetricRegistry.name(hikariConfig.getPoolName(), "pool", "Connection99Percent"), new Connection99Percent(timer, expected99thPercentile));
}
}
}
private CodahaleHealthChecker()
{
// private constructor
}
private static class ConnectivityHealthCheck extends HealthCheck
{
private final HikariPool pool;
private final long checkTimeoutMs;
ConnectivityHealthCheck(final HikariPool pool, final long checkTimeoutMs)
{
this.pool = pool;
this.checkTimeoutMs = (checkTimeoutMs > 0 && checkTimeoutMs != Integer.MAX_VALUE ? checkTimeoutMs : TimeUnit.SECONDS.toMillis(10));
}
/** {@inheritDoc} */
@Override
protected Result check() throws Exception
{
try (Connection connection = pool.getConnection(checkTimeoutMs)) {
return Result.healthy();
}
catch (SQLException e) {
return Result.unhealthy(e);
}
}
}
private static class Connection99Percent extends HealthCheck
{
private final Timer waitTimer;
private final long expected99thPercentile;
Connection99Percent(final Timer waitTimer, final long expected99thPercentile)
{
this.waitTimer = waitTimer;
this.expected99thPercentile = expected99thPercentile;
}
/** {@inheritDoc} */
@Override
protected Result check() throws Exception
{
final long the99thPercentile = TimeUnit.NANOSECONDS.toMillis(Math.round(waitTimer.getSnapshot().get99thPercentile()));
return the99thPercentile <= expected99thPercentile ? Result.healthy() : Result.unhealthy("99th percentile connection wait time of %dms exceeds the threshold %dms", the99thPercentile, expected99thPercentile);
}
}
}