org.apache.flume.api

Class FailoverRpcClient

java.lang.Object

org.apache.flume.api.AbstractRpcClient

org.apache.flume.api.FailoverRpcClient

All Implemented Interfaces:

RpcClient

public class FailoverRpcClient
extends AbstractRpcClient
implements RpcClient

Avro/Netty implementation of RpcClient which supports failover. This takes a list of hostname port combinations and connects to the next available (looping back to the first) host, from a given list of agents in the order provided. The properties used to build a FailoverRpcClient must have:

hosts = alias_for_host1 alias_for_host2

...

hosts.alias_for_host1 = hostname1:port1.

hosts.alias_for_host2 = hostname2:port2.

etc

Optionally it can also have a

batch-size = batchSize max-attempts = maxAttempts Given a failure, this client will attempt to append to maxAttempts clients in the hosts list immediately following the failed host (looping back to the beginning of the hosts list.

Field Summary

Fields inherited from class org.apache.flume.api.AbstractRpcClient

batchSize, connectTimeout, requestTimeout

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FailoverRpcClient()

Method Summary

Modifier and Type	Method and Description
void	append(Event event) Tries to append an event to the currently connected client.
void	appendBatch(List<Event> events) Tries to append a list of events to the currently connected client.
void	close() Close the connection.
void	configure(Properties properties) Configure the client using the given properties object.
protected InetSocketAddress	getLastConnectedServerAddress() Get the last socket address this client connected to.
protected Integer	getMaxTries() Get the maximum number of "failed" hosts the client will try to establish connection to before throwing an exception.
boolean	isActive() Returns true if this object appears to be in a usable state, and it returns false if this object is permanently disabled.

Methods inherited from class org.apache.flume.api.AbstractRpcClient

getBatchSize, parseBatchSize

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flume.api.RpcClient

getBatchSize

Constructor Detail

FailoverRpcClient

protected FailoverRpcClient()

Method Detail

getMaxTries

protected Integer getMaxTries()

Get the maximum number of "failed" hosts the client will try to establish connection to before throwing an exception. Failed = was able to set up a connection, but failed / returned error when the client tried to send data,

Returns:

The maximum number of failed retries

append

public void append(Event event)
            throws EventDeliveryException

Tries to append an event to the currently connected client. If it cannot send the event, it tries to send to next available host

Specified by:

append in interface RpcClient

Specified by:

append in class AbstractRpcClient

Parameters:

event - The event to be appended.

Throws:

EventDeliveryException

appendBatch

public void appendBatch(List<Event> events)
                 throws EventDeliveryException

Tries to append a list of events to the currently connected client. If it cannot send the event, it tries to send to next available host

Specified by:

appendBatch in interface RpcClient

Specified by:

appendBatch in class AbstractRpcClient

Parameters:

events - The events to be appended.

Throws:

EventDeliveryException

isActive

public boolean isActive()

Description copied from interface: RpcClient

Returns true if this object appears to be in a usable state, and it returns false if this object is permanently disabled.

If this method returns false, an application must call RpcClient.close() on this object to clean up system resources.

Specified by:

isActive in interface RpcClient

Specified by:

isActive in class AbstractRpcClient

close

public void close()
           throws FlumeException

Close the connection. This function is safe to call over and over.

Specified by:

close in interface RpcClient

Specified by:

close in class AbstractRpcClient

Throws:

FlumeException

getLastConnectedServerAddress

protected InetSocketAddress getLastConnectedServerAddress()

Get the last socket address this client connected to. No guarantee this will be the next it will connect to. If this host is down, it will connect to another host. To be used only from the unit tests!

Returns:

The last socket address this client connected to

configure

public void configure(Properties properties)
               throws FlumeException

Description copied from class: AbstractRpcClient

Configure the client using the given properties object.

Specified by:

configure in class AbstractRpcClient

Throws:

FlumeException - if the client can not be configured using this method, or if the client was already configured once.