software.amazon.jdbc.plugin.failover

Class FailoverConnectionPlugin

java.lang.Object

software.amazon.jdbc.plugin.AbstractConnectionPlugin

software.amazon.jdbc.plugin.failover.FailoverConnectionPlugin

All Implemented Interfaces:

ConnectionPlugin, StateSnapshotProvider

public class FailoverConnectionPlugin
extends AbstractConnectionPlugin
implements StateSnapshotProvider

This plugin provides cluster-aware failover features. The plugin switches connections upon detecting communication related exceptions and/or cluster topology changes.

Field Summary

Fields

Modifier and Type	Field and Description
protected @Nullable java.lang.String	closedReason
static AwsWrapperProperty	ENABLE_CLUSTER_AWARE_FAILOVER
static AwsWrapperProperty	ENABLE_CONNECT_FAILOVER
protected boolean	enableConnectFailover
protected boolean	enableFailoverSetting
static AwsWrapperProperty	FAILOVER_CLUSTER_TOPOLOGY_REFRESH_RATE_MS
static AwsWrapperProperty	FAILOVER_MODE
static AwsWrapperProperty	FAILOVER_READER_CONNECT_TIMEOUT_MS
static AwsWrapperProperty	FAILOVER_TIMEOUT_MS
static AwsWrapperProperty	FAILOVER_WRITER_RECONNECT_INTERVAL_MS
protected int	failoverClusterTopologyRefreshRateMsSetting
protected @Nullable FailoverMode	failoverMode
protected int	failoverReaderConnectTimeoutMsSetting
protected int	failoverTimeoutMsSetting
protected int	failoverWriterReconnectIntervalMsSetting
protected java.util.Properties	properties
protected @Nullable ReaderFailoverHandler	readerFailoverHandler
static AwsWrapperProperty	SKIP_FAILOVER_ON_INTERRUPTED_THREAD
static AwsWrapperProperty	TELEMETRY_FAILOVER_ADDITIONAL_TOP_TRACE
protected @Nullable WriterFailoverHandler	writerFailoverHandler

Constructor Summary

Constructors

Constructor and Description
FailoverConnectionPlugin(FullServicesContainer servicesContainer, java.util.Properties properties)

Method Summary

Modifier and Type	Method and Description
java.sql.Connection	connect(java.lang.String driverProtocol, HostSpec hostSpec, java.util.Properties props, boolean isInitialConnection, JdbcCallable<java.sql.Connection,java.sql.SQLException> connectFunc) Establishes a connection to the given host using the given driver protocol and properties.
protected java.sql.Connection	createConnectionForHost(HostSpec baseHostSpec) Creates a new physical connection for the given HostSpec.
protected <E extends java.lang.Exception> void	dealWithIllegalStateException(java.lang.IllegalStateException e, java.lang.Class<E> exceptionClass)
<T,E extends java.lang.Exception> T	execute(java.lang.Class<T> resultClass, java.lang.Class<E> exceptionClass, java.lang.Object methodInvokeOn, java.lang.String methodName, JdbcCallable<T,E> jdbcMethodFunc, @Nullable java.lang.Object[] jdbcMethodArgs)
protected void	failover(@Nullable HostSpec failedHost, boolean isInitialConnection) Initiates the failover procedure.
protected void	failoverReader(@Nullable HostSpec failedHostSpec)
protected void	failoverWriter(boolean isInitialConnection)
java.util.List<Pair<java.lang.String,java.lang.Object>>	getSnapshotState()
java.util.Set<java.lang.String>	getSubscribedMethods()
protected void	initFailoverMode()
void	initHostProvider(java.lang.String driverProtocol, java.lang.String initialUrl, java.util.Properties properties, HostListProviderService hostListProviderService, JdbcCallable<java.lang.Void,java.sql.SQLException> initHostProviderFunc)
protected void	invalidateCurrentConnection()
boolean	isFailoverEnabled()
void	notifyNodeListChanged(java.util.Map<java.lang.String,java.util.EnumSet<NodeChangeOptions>> changes)
protected void	pickNewConnection()
protected boolean	shouldExceptionTriggerConnectionSwitch(java.lang.Throwable t)
protected void	throwFailoverSuccessException()
protected void	updateTopology(boolean forceUpdate)

Methods inherited from class software.amazon.jdbc.plugin.AbstractConnectionPlugin

acceptsStrategy, forceConnect, getHostSpecByStrategy, getHostSpecByStrategy, notifyConnectionChanged

Methods inherited from class java.lang.Object

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

Field Detail

properties

protected final java.util.Properties properties

enableFailoverSetting

protected boolean enableFailoverSetting

enableConnectFailover

protected boolean enableConnectFailover

failoverTimeoutMsSetting

protected int failoverTimeoutMsSetting

failoverClusterTopologyRefreshRateMsSetting

protected int failoverClusterTopologyRefreshRateMsSetting

failoverWriterReconnectIntervalMsSetting

protected int failoverWriterReconnectIntervalMsSetting

failoverReaderConnectTimeoutMsSetting

protected int failoverReaderConnectTimeoutMsSetting

failoverMode

protected @Nullable FailoverMode failoverMode

closedReason

protected @Nullable java.lang.String closedReason

writerFailoverHandler

protected @Nullable WriterFailoverHandler writerFailoverHandler

readerFailoverHandler

protected @Nullable ReaderFailoverHandler readerFailoverHandler

FAILOVER_CLUSTER_TOPOLOGY_REFRESH_RATE_MS

public static final AwsWrapperProperty FAILOVER_CLUSTER_TOPOLOGY_REFRESH_RATE_MS

FAILOVER_TIMEOUT_MS

public static final AwsWrapperProperty FAILOVER_TIMEOUT_MS

FAILOVER_WRITER_RECONNECT_INTERVAL_MS

public static final AwsWrapperProperty FAILOVER_WRITER_RECONNECT_INTERVAL_MS

FAILOVER_READER_CONNECT_TIMEOUT_MS

public static final AwsWrapperProperty FAILOVER_READER_CONNECT_TIMEOUT_MS

ENABLE_CLUSTER_AWARE_FAILOVER

public static final AwsWrapperProperty ENABLE_CLUSTER_AWARE_FAILOVER

ENABLE_CONNECT_FAILOVER

public static final AwsWrapperProperty ENABLE_CONNECT_FAILOVER

FAILOVER_MODE

public static final AwsWrapperProperty FAILOVER_MODE

TELEMETRY_FAILOVER_ADDITIONAL_TOP_TRACE

public static final AwsWrapperProperty TELEMETRY_FAILOVER_ADDITIONAL_TOP_TRACE

SKIP_FAILOVER_ON_INTERRUPTED_THREAD

public static final AwsWrapperProperty SKIP_FAILOVER_ON_INTERRUPTED_THREAD

Constructor Detail

FailoverConnectionPlugin

public FailoverConnectionPlugin(FullServicesContainer servicesContainer,
                                java.util.Properties properties)

Method Detail

getSubscribedMethods

public java.util.Set<java.lang.String> getSubscribedMethods()

Specified by:

getSubscribedMethods in interface ConnectionPlugin

Specified by:

getSubscribedMethods in class AbstractConnectionPlugin

execute

public <T,E extends java.lang.Exception> T execute(java.lang.Class<T> resultClass,
                                                   java.lang.Class<E> exceptionClass,
                                                   java.lang.Object methodInvokeOn,
                                                   java.lang.String methodName,
                                                   JdbcCallable<T,E> jdbcMethodFunc,
                                                   @Nullable java.lang.Object[] jdbcMethodArgs)
                                            throws E extends java.lang.Exception

Specified by:

execute in interface ConnectionPlugin

Overrides:

execute in class AbstractConnectionPlugin

Throws:

E extends java.lang.Exception

initHostProvider

public void initHostProvider(java.lang.String driverProtocol,
                             java.lang.String initialUrl,
                             java.util.Properties properties,
                             HostListProviderService hostListProviderService,
                             JdbcCallable<java.lang.Void,java.sql.SQLException> initHostProviderFunc)
                      throws java.sql.SQLException

Specified by:

initHostProvider in interface ConnectionPlugin

Overrides:

initHostProvider in class AbstractConnectionPlugin

Throws:

java.sql.SQLException

notifyNodeListChanged

public void notifyNodeListChanged(java.util.Map<java.lang.String,java.util.EnumSet<NodeChangeOptions>> changes)

Specified by:

notifyNodeListChanged in interface ConnectionPlugin

Overrides:

notifyNodeListChanged in class AbstractConnectionPlugin

isFailoverEnabled

public boolean isFailoverEnabled()

initFailoverMode

protected void initFailoverMode()

updateTopology

protected void updateTopology(boolean forceUpdate)
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

createConnectionForHost

protected java.sql.Connection createConnectionForHost(HostSpec baseHostSpec)
                                               throws java.sql.SQLException

Creates a new physical connection for the given HostSpec.

Parameters:

baseHostSpec - The host info instance to base the connection off of.

Returns:

The new Connection instance.

Throws:

java.sql.SQLException - if an error occurs

dealWithIllegalStateException

protected <E extends java.lang.Exception> void dealWithIllegalStateException(java.lang.IllegalStateException e,
                                                                             java.lang.Class<E> exceptionClass)
                                                                      throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

failover

protected void failover(@Nullable HostSpec failedHost,
                        boolean isInitialConnection)
                 throws java.sql.SQLException

Initiates the failover procedure. This process tries to establish a new connection to an instance in the topology.

Parameters:

failedHost - The host with network errors.

isInitialConnection - The flag that indicates whether it is an initial connection

Throws:

java.sql.SQLException - if an error occurs

failoverReader

protected void failoverReader(@Nullable HostSpec failedHostSpec)
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

throwFailoverSuccessException

protected void throwFailoverSuccessException()
                                      throws java.sql.SQLException

Throws:

java.sql.SQLException

failoverWriter

protected void failoverWriter(boolean isInitialConnection)
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

invalidateCurrentConnection

protected void invalidateCurrentConnection()

pickNewConnection

protected void pickNewConnection()
                          throws java.sql.SQLException

Throws:

java.sql.SQLException

shouldExceptionTriggerConnectionSwitch

protected boolean shouldExceptionTriggerConnectionSwitch(java.lang.Throwable t)

connect

public java.sql.Connection connect(java.lang.String driverProtocol,
                                   HostSpec hostSpec,
                                   java.util.Properties props,
                                   boolean isInitialConnection,
                                   JdbcCallable<java.sql.Connection,java.sql.SQLException> connectFunc)
                            throws java.sql.SQLException

Description copied from interface: ConnectionPlugin

Establishes a connection to the given host using the given driver protocol and properties. If a non-default ConnectionProvider has been set with Driver.setCustomConnectionProvider(ConnectionProvider) and ConnectionProvider.acceptsUrl(String, HostSpec, Properties) returns true for the given protocol, host, and properties, the connection will be created by the non-default ConnectionProvider. Otherwise, the connection will be created by the default ConnectionProvider. The default ConnectionProvider will be DriverConnectionProvider for connections requested via the DriverManager and DataSourceConnectionProvider for connections requested via an AwsWrapperDataSource.

Specified by:

connect in interface ConnectionPlugin

Overrides:

connect in class AbstractConnectionPlugin

Parameters:

driverProtocol - the driver protocol that should be used to establish the connection

hostSpec - the host details for the desired connection

props - the connection properties

isInitialConnection - a boolean indicating whether the current Connection is establishing an initial physical connection to the database or has already established a physical connection in the past

connectFunc - the function to call to continue the connect request down the connect pipeline

Returns:

a Connection to the requested host

Throws:

java.sql.SQLException - if there was an error establishing a Connection to the requested host

getSnapshotState

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

Specified by:

getSnapshotState in interface StateSnapshotProvider

Overrides:

getSnapshotState in class AbstractConnectionPlugin