software.amazon.jdbc.plugin.customendpoint

Class CustomEndpointMonitorImpl

java.lang.Object

software.amazon.jdbc.util.monitoring.AbstractMonitor

software.amazon.jdbc.plugin.customendpoint.CustomEndpointMonitorImpl

All Implemented Interfaces:

java.lang.Runnable, CustomEndpointMonitor, Monitor, StateSnapshotProvider

public class CustomEndpointMonitorImpl
extends AbstractMonitor
implements CustomEndpointMonitor, StateSnapshotProvider

The default custom endpoint monitor implementation. This class uses a background thread to monitor a given custom endpoint for custom endpoint information and future changes to the custom endpoint.

Field Summary

Fields

Modifier and Type	Field and Description
protected static long	CUSTOM_ENDPOINT_INFO_EXPIRATION_NANO
protected HostSpec	customEndpointHostSpec
protected static CacheMap<java.lang.String,CustomEndpointInfo>	customEndpointInfoCache
protected java.lang.String	endpointIdentifier
protected java.util.concurrent.atomic.AtomicBoolean	hasConnectionIssue
protected long	maxRefreshRateNano
protected long	minRefreshRateNano
protected static long	MONITOR_TERMINATION_TIMEOUT_SEC
protected software.amazon.awssdk.services.rds.RdsClient	rdsClient
protected int	refreshRateBackoffFactor
protected long	refreshRateNano
protected java.util.concurrent.atomic.AtomicBoolean	refreshRequired
protected software.amazon.awssdk.regions.Region	region
protected StorageService	storageService
protected static long	UNAUTHORIZED_SLEEP_NANO

Fields inherited from class software.amazon.jdbc.util.monitoring.AbstractMonitor

lastActivityTimestampNanos, monitorExecutor, state, stop, terminationTimeoutSec

Constructor Summary

Constructors

Constructor and Description

CustomEndpointMonitorImpl(StorageService storageService, TelemetryFactory telemetryFactory, HostSpec customEndpointHostSpec, java.lang.String endpointIdentifier, software.amazon.awssdk.regions.Region region, long refreshRateNano, int refreshRateBackoffFactor, long maxRefreshRateNano, java.util.function.BiFunction<HostSpec,software.amazon.awssdk.regions.Region,software.amazon.awssdk.services.rds.RdsClient> rdsClientFunc) Constructs a CustomEndpointMonitorImpl instance for the host specified by customEndpointHostSpec.

Method Summary

Modifier and Type	Method and Description
static void	clearCache() Clears the shared custom endpoint information cache.
void	close() Closes all resources used by this monitor.
java.util.List<Pair<java.lang.String,java.lang.Object>>	getSnapshotState()
boolean	hasCustomEndpointInfo() Indicates whether the monitor has info about the custom endpoint or not.
void	monitor() Analyzes a given custom endpoint for changes to custom endpoint information.
void	requestCustomEndpointInfoUpdate()
protected void	sleep(long durationNano)
protected void	sleepIgnoringRefreshRequests(long durationNano) Sleeps for the given duration without being woken early by connection-driven refresh requests (see refreshRequired).
protected void	slowdownRefreshRate()
protected void	speedupRefreshRate()

Methods inherited from class software.amazon.jdbc.util.monitoring.AbstractMonitor

canDispose, getLastActivityTimestampNanos, getState, run, start, stop

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface software.amazon.jdbc.util.monitoring.Monitor

canDispose, getLastActivityTimestampNanos, getState, start, stop

Field Detail

customEndpointInfoCache

protected static final CacheMap<java.lang.String,CustomEndpointInfo> customEndpointInfoCache

CUSTOM_ENDPOINT_INFO_EXPIRATION_NANO

protected static final long CUSTOM_ENDPOINT_INFO_EXPIRATION_NANO

UNAUTHORIZED_SLEEP_NANO

protected static final long UNAUTHORIZED_SLEEP_NANO

MONITOR_TERMINATION_TIMEOUT_SEC

protected static final long MONITOR_TERMINATION_TIMEOUT_SEC

See Also:

Constant Field Values

refreshRequired

protected final java.util.concurrent.atomic.AtomicBoolean refreshRequired

hasConnectionIssue

protected final java.util.concurrent.atomic.AtomicBoolean hasConnectionIssue

rdsClient

protected final software.amazon.awssdk.services.rds.RdsClient rdsClient

customEndpointHostSpec

protected final HostSpec customEndpointHostSpec

endpointIdentifier

protected final java.lang.String endpointIdentifier

region

protected final software.amazon.awssdk.regions.Region region

minRefreshRateNano

protected long minRefreshRateNano

maxRefreshRateNano

protected long maxRefreshRateNano

refreshRateNano

protected long refreshRateNano

refreshRateBackoffFactor

protected int refreshRateBackoffFactor

storageService

protected final StorageService storageService

Constructor Detail

CustomEndpointMonitorImpl

public CustomEndpointMonitorImpl(StorageService storageService,
                                 TelemetryFactory telemetryFactory,
                                 HostSpec customEndpointHostSpec,
                                 java.lang.String endpointIdentifier,
                                 software.amazon.awssdk.regions.Region region,
                                 long refreshRateNano,
                                 int refreshRateBackoffFactor,
                                 long maxRefreshRateNano,
                                 java.util.function.BiFunction<HostSpec,software.amazon.awssdk.regions.Region,software.amazon.awssdk.services.rds.RdsClient> rdsClientFunc)

Constructs a CustomEndpointMonitorImpl instance for the host specified by customEndpointHostSpec.

Parameters:

storageService - The storage service used to store the set of allowed/blocked hosts according to the custom endpoint info.

telemetryFactory - The telemetry factory used to create telemetry data.

customEndpointHostSpec - The host information for the custom endpoint to be monitored.

endpointIdentifier - An endpoint identifier.

region - The region of the custom endpoint to be monitored.

refreshRateNano - Controls how often the custom endpoint information should be fetched and analyzed for changes. The value specified should be in nanoseconds.

maxRefreshRateNano - The maximum refresh rate allowed for the custom endpoint monitor.

refreshRateBackoffFactor - The backoff factor to use when slowing down the refresh rate.

rdsClientFunc - The function to call to create the RDS client that will fetch custom endpoint information.

Method Detail

monitor

public void monitor()

Analyzes a given custom endpoint for changes to custom endpoint information.

Specified by:

monitor in interface Monitor

speedupRefreshRate

protected void speedupRefreshRate()

slowdownRefreshRate

protected void slowdownRefreshRate()

sleep

protected void sleep(long durationNano)
              throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

sleepIgnoringRefreshRequests

protected void sleepIgnoringRefreshRequests(long durationNano)
                                     throws java.lang.InterruptedException

Sleeps for the given duration without being woken early by connection-driven refresh requests (see refreshRequired). This is used on the error/backoff paths so that the throttling backoff, and other error delays, cannot be bypassed by incoming connections. If it could, the monitor would keep issuing RDS API calls as fast as connections arrive, defeating the built-in rate limiting and sustaining the throttling. The sleep still returns promptly when the monitor is stopped or the thread is interrupted.

Parameters:

durationNano - the time to sleep, in nanoseconds.

Throws:

java.lang.InterruptedException - if the thread is interrupted while sleeping.

hasCustomEndpointInfo

public boolean hasCustomEndpointInfo()

Description copied from interface: CustomEndpointMonitor

Indicates whether the monitor has info about the custom endpoint or not. This will be false if the monitor is new and has not yet had enough time to fetch the info.

Specified by:

hasCustomEndpointInfo in interface CustomEndpointMonitor

Returns:

true if the monitor has info about the custom endpoint, otherwise returns false.

requestCustomEndpointInfoUpdate

public void requestCustomEndpointInfoUpdate()

Specified by:

requestCustomEndpointInfoUpdate in interface CustomEndpointMonitor

close

public void close()

Description copied from interface: Monitor

Closes all resources used by this monitor. This method will be called as part of Monitor.stop().

Specified by:

close in interface Monitor

Overrides:

close in class AbstractMonitor

clearCache

public static void clearCache()

Clears the shared custom endpoint information cache.

getSnapshotState

public java.util.List<Pair<java.lang.String,java.lang.Object>> getSnapshotState()

Specified by:

getSnapshotState in interface StateSnapshotProvider