Accessing properties set at runtime using property ${} notation in Mule flow

In a Mule flow, I have a property set in my flow as follows:

    <set-property propertyName="certPath" value="/tmp/#[aVariable]/certificate.pem" doc:name="Property"/>

I'm now trying to use it inside my sftp outbound-endpoint identityFile attribute, as follows: identityFile="${certPath}"

This does not work and takes in the placeholder as a string (as is.)

Am I missing something in the way properties should be set and then accessed?

I have also tried to add a message property in the session scope, but then when trying ${session.certPath} nothing gets evaled either.

Solution

In order to access property set during a flow you need to use the Mule Expression language.

Try using the following to access your property.

#[message.outboundProperties['certPath']]

Note: This works only when the property is accessed in the same flow.

The ant style access ${session.certPath} is for loading properties from properties file.

Refer the following link for more details on MEL.

Hope this helps.