Yay! 2009/4/2 Claus Ibsen <claus.ib...@gmail.com>: > Hi > > The default error handler is now changed in Camel 2.0. > > On Wed, Apr 1, 2009 at 11:58 AM, Claus Ibsen <claus.ib...@gmail.com> wrote: >> On Wed, Apr 1, 2009 at 11:51 AM, Roman Kalukiewicz >> <roman.kalukiew...@gmail.com> wrote: >>> I would definitely support #1. >>> >>> #3 is not so good as a default one because it can cause some side effects >>> like when you use in-out JMS endpoint. If nothing listens to the queue, then >>> you will end up with 6 messages in request queue instead of one (assuming >>> you don't use transactions). >>> >>> BTW Last time when I was looking at it there was no easy way to do #3 even >>> if you want it (to have redeliveries, but send an exception in case they >>> fail). >> Yeah #3 should really be let TransactionErrorHandler support onException. >> Allowing you to catch certain exceptions and let it be handled so >> there are no rollback. >> >> >>> >>> Roman >>> >>> 2009/3/31 Claus Ibsen <claus.ib...@gmail.com> >>> >>>> Hi >>>> >>>> As we work on the Camel 2.0 I would suggest that we start a discussion >>>> what should be the preferred error handler defaults in Camel 2.0. >>>> What we currently have is the DLC is default and it does 6 retries >>>> with 1 sec apart and then just log an ERROR and ends the exchange. >>>> >>>> We have 3 different error handler types >>>> - no error handler (= disabled) >>>> - DeadLetterChannel (= default in 1.x) >>>> - TransactionErrorHandler (= using Spring TX) >>>> >>>> As people can use Camel in different runtimes and with different needs >>>> for error handling we cannot have a default that fits all situations. >>>> >>>> We could for instance do >>>> >>>> 1) >>>> Disable error handling by default. >>>> >>>> This would be the least surprises for end users. If there is some >>>> exception then it would be propagated back to the caller. >>>> We could even optimize the logic in Camel to avoid adding the >>>> interceptor that adds the noErrorHandler. >>>> >>>> +1 from me >>>> >>>> >>>> 2) >>>> Keep it as is >>>> big -1 from me. We have the luxury of being able to change defaults >>>> before 2.0 is released. So we should do it!!! >>>> >>>> >>>> 3) >>>> Use DeadLetterChannel but add a feature so it avoids failure handling >>>> it by default. So it will be able to do retries but if it fails all >>>> together >>>> it will propagate the exception back to the caller as if the have been >>>> no error handler at all. >>>> >>>> This feature could also be useable for end users in other situations, >>>> eg retry IOExceptions and in case of a all attempts failed then >>>> propgate the excpetion back to the caller. >>>> >>>> What should the option name be: >>>> - moveToDeadLetterQueue=false >>>> - handled=false (like the handled we have at onException) >>>> >>>> +1 as well. We can even do #1 and #3 >>>> >>>> >>>> 4) >>>> For TX its mostly all the Spring XML garbage that is needed to setup >>>> TX that can be a bit hard to get configure correct. >>>> So the JMS component have a transacted=true option to allow to do this >>>> itself or discover if there is a Spring TX manager already. >>>> >>>> Maybe we can default to use transactionErrorHandler if we can find a >>>> Spring TX manager. But this would only work for certain transports >>>> that support TX, and that is mostly only JMS and JDBC. >>>> >>>> So what should happens for routing not involving those, eg camel-cxf, >>>> over file to a mail etc? >>>> Could be confusing, if Camel uses TX for certain routes and the other >>>> for the other routes. >>>> >>>> So what we have now with the transacted=true option is good as end >>>> users need to explicit declare this option. >>>> We could maybe add this for the JDBC based components as well: JPA, JDBC, >>>> SQL. >>>> >>>> >>>> Any thoughts? >>>> >>>> >>>> >>>> -- >>>> Claus Ibsen >>>> Apache Camel Committer >>>> >>>> Open Source Integration: http://fusesource.com >>>> Blog: http://davsclaus.blogspot.com/ >>>> Twitter: http://twitter.com/davsclaus >>>> >>> >> >> >> >> -- >> Claus Ibsen >> Apache Camel Committer >> >> Open Source Integration: http://fusesource.com >> Blog: http://davsclaus.blogspot.com/ >> Twitter: http://twitter.com/davsclaus >> Apache Camel Reference Card: >> http://refcardz.dzone.com/refcardz/enterprise-integration >> > > > > -- > Claus Ibsen > Apache Camel Committer > > Open Source Integration: http://fusesource.com > Blog: http://davsclaus.blogspot.com/ > Twitter: http://twitter.com/davsclaus > Apache Camel Reference Card: > http://refcardz.dzone.com/refcardz/enterprise-integration >
-- James ------- http://macstrac.blogspot.com/ Open Source Integration http://fusesource.com/
