ru.kiryam.storm.rabbitmq

Class TupleToMessage

java.lang.Object

ru.kiryam.storm.rabbitmq.TupleToMessage

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

TupleToMessageNonDynamic

public abstract class TupleToMessage
extends Object
implements Serializable

This interface describes an object that will perform the work of mapping incoming Tuples to Message objects for posting on a RabbitMQ exchange.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
TupleToMessage()

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract String	determineExchangeName(backtype.storm.tuple.Tuple input) Determine the exchange where the message is published to.
protected String	determineRoutingKey(backtype.storm.tuple.Tuple input) Determine the routing key used for this message.
protected abstract byte[]	extractBody(backtype.storm.tuple.Tuple input) Extract message body as a byte array from the incoming tuple.
protected void	prepare(Map stormConfig)
protected Message	produceMessage(backtype.storm.tuple.Tuple input) Convert the incoming Tuple on the Storm stream to a Message for posting to RabbitMQ.
protected String	specifyContentEncoding(backtype.storm.tuple.Tuple input) Specify message body content encoding.
protected String	specifyContentType(backtype.storm.tuple.Tuple input) Specify message body content type.
protected Map<String,Object>	specifyHeaders(backtype.storm.tuple.Tuple input) Specify the headers to be sent along with this message.
protected boolean	specifyMessagePersistence(backtype.storm.tuple.Tuple input) Specify whether each individual message should make use of message persistence when it's on a rabbitmq queue.

Methods inherited from class java.lang.Object

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

Constructor Detail

TupleToMessage

public TupleToMessage()

Method Detail

prepare

protected void prepare(Map stormConfig)

produceMessage

protected Message produceMessage(backtype.storm.tuple.Tuple input)

Convert the incoming Tuple on the Storm stream to a Message for posting to RabbitMQ.

Parameters:

input - The incoming Tuple from Storm

Returns:

The Message for the RabbitMQProducer to publish. If transformation fails this should return Message.NONE.

extractBody

protected abstract byte[] extractBody(backtype.storm.tuple.Tuple input)

Extract message body as a byte array from the incoming tuple. This is required. This implementation must handle errors and should return null upon on unresolvable errors.

Parameters:

input - the incoming tuple

Returns:

message body as a byte array or null if extraction cannot be performed

determineExchangeName

protected abstract String determineExchangeName(backtype.storm.tuple.Tuple input)

Determine the exchange where the message is published to. This can be derived based on the incoming tuple or a fixed value.

Parameters:

input - the incoming tuple

Returns:

the exchange where the message is published to.

determineRoutingKey

protected String determineRoutingKey(backtype.storm.tuple.Tuple input)

Determine the routing key used for this message. This can be derived based on the incoming tuple or a fixed value. Default implementation provides no routing key.

Parameters:

input - the incoming tuple

Returns:

the routing key for this message

specifyHeaders

protected Map<String,Object> specifyHeaders(backtype.storm.tuple.Tuple input)

Specify the headers to be sent along with this message. The default implementation return an empty map.

Parameters:

input - the incoming tuple

Returns:

the headers as a map

specifyContentType

protected String specifyContentType(backtype.storm.tuple.Tuple input)

Specify message body content type. Default implementation skips the provision of this detail.

Parameters:

input - the incoming tuple

Returns:

content type

specifyContentEncoding

protected String specifyContentEncoding(backtype.storm.tuple.Tuple input)

Specify message body content encoding. Default implementation skips the provision of this detail.

Parameters:

input - the incoming tuple

Returns:

content encoding

specifyMessagePersistence

protected boolean specifyMessagePersistence(backtype.storm.tuple.Tuple input)

Specify whether each individual message should make use of message persistence when it's on a rabbitmq queue. This does imply queue durability or high availability or just avoidance of message loss. To accomplish that please read rabbitmq docs on High Availability, Publisher Confirms and Queue Durability in addition to having this return true. By default, message persistence returns false.

Parameters:

input - the incoming tuple

Returns:

whether the message should be persistent to disk or not. Defaults to not.