Trouble Updating Session In If block

[Jason Finch]

So, I want to update a session variable if this scala function returns true.  I set it to always return true to debug this
part of the code.  However, when I run and I print out the session variables at the end of the run the session variable "testNewSeg" is

never updated even though i know that it reaches the code inside the 'if' block. If anyone knows the solution to this problem

please let me know. Thanks! 


.exec{session =>
  if (newSegmentTest(session,"activity_server_id","isNewSeg"))
    {exec(session => session
            .set("testNewSeg","true")
    )}
  session
}

[Barry Perez]

Hi Jason,

Ref the session API documentation: http://gatling.io/docs/current/session/session_api/

---

Warning

Session instances are immutable!

Why is that so? Because Sessions are messages that are dealt with in a multi-threaded concurrent way, so immutability is the best way to deal with state without relying on synchronization and blocking.

A very common pitfall is to forget that set and setAll actually return new instances.

---

So, remove the last "session" and you should be good to go.

Cheers,

Barry

[Barry Perez]

Example:

.exec{session =>

  if (newSegmentTest(session,"activity_server_id","isNewSeg")) {

    session.set("testNewSeg","true")

  } else {

  session

[Jason Finch]

When I remove the last session I get a compile errors:

"Missing parameter type {exec(session => session "

"type mismatch;

 found   : Unit

 required: io.gatling.commons.validation.Validation[io.gatling.core.session.Session]

      .exec{session => if(newSegmentTest(session,"activity_server_id","isNewSeg"))"

.exec{session => if(newSegmentTest(session,"activity_server_id","isNewSeg"))

[Barry Perez]

Hi,

Try following the example I posted a few minutes ago - you have to return a session regardless of whether you modify it or not - but since session.set returns an immutable session object then you return either that OR the original session object (use if/else)

Barry

[Jason Finch]

Hey Barry, 

Thank you so much! New to Gatling and Scala. This should open up a lot for me.  

[Barry Perez]

Hi Jason,

No problems - glad it was helpful... Enjoy!

Barry