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From Mark Payne <marka...@hotmail.com>
Subject Re: Expression language support in EvaluateXPath
Date Fri, 14 Jul 2017 12:45:35 GMT
Hello,

In glancing at the processor I believe the reason that the Expression Language is not supported
is due to efficiency purposes.
The processor grabs up to 50 FlowFiles, then compiles the XPath Expressions and runs them
over all 50 FlowFiles. If we
did support Expression Language and EL were used, we would have to re-compile the XPath Expression
for every FlowFile.
That said, there's no reason we can't do that. However, in order to avoid hurting performance
when not necessary it would need
to contain a bit of logic to pre-compile the expressions that aren't configured with Expression
Language, so it's not a trivial change.
If you're interested in updating the Processor, though, I'd be happy to review it.

Thanks
-Mark



> On Jul 14, 2017, at 6:51 AM, claudiu-stanciu <claudiu.a.stanciu@gmail.com> wrote:
> 
> Hello,
> 
> I saw that  EvaluateXPath declares that expression language is not supported
> <https://github.com/apache/nifi/blob/master/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/EvaluateXPath.java#L209>
 
> 
> My question is: can we have support for expression language with XPath ?
> (I'm not an expression language or xpath expert :) ).
> 
> This would be nice when you want to pass the xpath from a content or an
> attribute.
> 
> Thank you
> 
> 
> 
> --
> View this message in context: http://apache-nifi-developer-list.39713.n7.nabble.com/Expression-language-support-in-EvaluateXPath-tp16441.html
> Sent from the Apache NiFi Developer List mailing list archive at Nabble.com.


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