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https://issues.apache.org/jira/browse/CAMEL-13077?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16746446#comment-16746446
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Paul Richardson commented on CAMEL-13077:
-----------------------------------------

*PR* -> [2719|https://github.com/apache/camel/pull/2719]

> Olingo4 Consumer appears to not work with backoffIdleThreshold
> --------------------------------------------------------------
>
>                 Key: CAMEL-13077
>                 URL: https://issues.apache.org/jira/browse/CAMEL-13077
>             Project: Camel
>          Issue Type: Bug
>          Components: camel-olingo4
>    Affects Versions: 2.21.0, 2.22.0, 2.23.0
>            Reporter: Paul Richardson
>            Priority: Major
>             Fix For: 2.22.3, 3.0.0, 2.23.2, 2.24.0
>
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> Looking into using {{backoffIdleThreshold}} for reducing the amount of 
> polling of OData consuming. So far I cannot see how it would work for the 
> [Olingo4Consumer|https://github.com/apache/camel/blob/master/components/camel-olingo4/camel-olingo4-component/src/main/java/org/apache/camel/component/olingo4/Olingo4Consumer.java].
>  Bear with me, this may get a little deep to follow!
> Hierarchy: ScheduledPollConsumer > AbstractApiConsumer > Olingo4Consumer
> SchedulePollConsumer maintains an 
> [idleCounter|https://github.com/apache/camel/blob/master/camel-core/src/main/java/org/apache/camel/support/ScheduledPollConsumer.java#L61],
>  which is incremented each time no messages are returned from polling. Once 
> the {{idleCounter}} starts to increment then this in turn starts to increment 
> the backoffCounter taking into account properties such as 
> {{backoffIdleThreshold}}, resulting in delaying polling etc.
> However, in order for {{idleCounter}} to increment, {{poll()}} methods must 
> return 0 messages. Since {{Olingo4Consumer}} defers its {{result[0]}} to 
> [ApiConsumer.getResultsProcessed()|https://github.com/apache/camel/blob/master/camel-core/src/main/java/org/apache/camel/support/component/ApiConsumerHelper.java#L85],
>  the results must be in a form that can be handled by this static method, 
> namely a List, an Iterable or an Array. Otherwise, the result is merely added 
> to the Exchange and the constant '1' is returned.
> Now here is the crux. OData services like to return a {{ClientEntitySet}} 
> hence when the result is passed to {{ApiConsumerHelper}}, it is none of the 
> expected types and 
> ['1'|https://github.com/apache/camel/blob/master/camel-core/src/main/java/org/apache/camel/support/component/ApiConsumerHelper.java#L128]
>  is therefore always returned. Consequently, the return value of {{poll()}} 
> is 1 hence {{idleCounter}} is never incremented.
> I hope that makes sense and if I have made a mistake then please let me know. 
> I think the way to handle this would be to put the entities of the 
> {{ClientEntitySet}} into the result rather than the set itself. That way 
> ApiConsumerHelper would understand a {{Collection}} as an {{Iterable}} and 
> return a proper value based on the size of the collection. Alternatively, if 
> the {{ClientEntitySet}} is desired as the result then maybe 
> {{ApiConsumerHelper}} needs to be extended in some way so as to correctly 
> handle a return value for {{poll()}}.
> Not sure which way to go on this so anxious to start a discussion.



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