CODEWITHSUNDEEP
apache-camelspring-camel
Raju Parashar
Raju Parashar

Reputation: 322

Persisting JMS Message Headers during Message Redelivery

We have a camel route where we read a message from an input queue, process it, set some JMS Header( using Exchange.getIn().setHeader(...) ) and then route the message to some output queue. During MQ Failover scenario, the message is redelivered. However, while the message is redelivered the JMS Headers which I put earlier are lost. Is there any way to preserve the JMS Headers even after redelivery ?

Upvotes: 0

Views: 721

Answers (2)

Mahdi Karami
Mahdi Karami

Reputation: 94

I have this problem, too. i'm forced to convert my objects to json and save in headers of jms. and after i convert again to object. it's worked for me!

Upvotes: -1

burki
burki

Reputation: 7005

JMS redelivery

No, not if the message is redelivered from the input queue. Simply because it is the same original message you received before. The JMS broker does not know anything about the modifications you did in the Camel route.

However, this is normally not a problem. Because on a redelivery, the same consumer consumes the message again and does the same modifications again on the message.

As soon as you reach a "transaction boundary" in your route (that means, something has done that cannot be repeated or would yield a different result), you should put the modified message on another queue to "save" its current state.

From there you can continue with another consumer and so forth. If you build a processing chain like this, your system is a Pipes and Filter EIP.

Camel redelivery

Another possibility is to use the Camel ErrorHandler. It handles errors on a single route-step level. It can also do retries, but then you have to make sure the message is correctly handled if all Camel retries fail (for example send the message to an error queue).

As long as the broker redelivery is the last resort for your message, you should build your system with potential redelivery in mind.

Upvotes: 1

Related Questions