question about message persistence ?

[xiaoyu1985ban]

Hi,every one.

when using a queue channel, the config is like following

<int:channel id="queueChannel"> 
    <int:queue capacity="50" /> 
</int:channel>

How should I recover the message in the channel from sudden power off ? I mean, there are messages in the channel, and at the power off time, the endpoints connectting to the channel has not received the messages yet.

I wonder if a channel can save the messages receives before it send them to its endpoint.The messages may be saved in a file, or a database and if necessary the channel can reread the messages.

any help will be appriciated~

[oleg.zhurakousky]

By default QueueChannel stores messages in memory, so you're right in the case of a crash, power-off etc., the messages are gonna be lost. However, you can use 'message-store' attribute on the 'queue' element to point to an implementation of the MessageStore strategy. We provide JdbcMessageStore allowing you to use RDBMS as a persistent store to back the QueueChannel. See more info here: http://static.springsource.org/sprin...-configuration

[xiaoyu1985ban]

thank oleg for quick answers.

Here is my config of using jdbcmessagestore:

<int:poller default="true" max-messages-per-poll="1" fixed-rate="2000">
</int:poller>
	
<int:channel id="dbBackedChannel">
<int:queue  capacity="10"  message-store="messageStore" />
</int:channel>
<int-jdbc:message-store id="messageStore" data-source="myDataSource"/>
<bean id="myDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
       <property name="driverClass" value="com.mysql.jdbc.Driver"/>
       <property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/test"/>
       <property name="user" value="ude"/>
       <property name="password" value="ude"/>
       <property name="initialPoolSize"><value>2</value></property>	
       <property name="minPoolSize"><value>1</value></property>
       <property name="maxPoolSize"><value>50</value></property>
       <property name="maxIdleTime"><value>1200</value></property>
       <property name="checkoutTimeout"><value>20000</value></property>
</bean>
<int:service-activator input-channel="dbBackedChannel"ref="messageHandler"></int:service-activator>
<int:inbound-channel-adapter channel="dbBackedChannel"
ref="messageProducer" method="produceMessage">
</int:inbound-channel-adapter>

And I have execute the ddl in database. Now It works fine, the message is stored in the table INT_MESSAGE_GROUP