Question

I’m trying to learn Mule ESB but get problems with example projects. Why are these lines
underlined red and not represented in the Message flow?

<expression-transformer name="returnAttachments">
        <return-argument evaluator="attachments-list" expression="*.txt,*.ozb,*.xml" optional="false"/>
    </expression-transformer>

I’ve cut and pasted these lines from mulesoft.org as part of a sample project.

Answer 1

@genjosanzo is right, the MEL equivalent would be:

<expression-transformer
        expression="#[($.value in message.inboundAttachments.entrySet() if $.key ~= '(.*\\.txt|.*\\.ozb|.*\\.xml)')]" />