Assertion returns null when json node has value

[Vivi]

Hi everyone!

I am trying to get and assert the vale of the node first from the following json response but the assertion returns null even when the value is returned :

{"registers":{

           "id": "123",
            "date": "2018-08-01",
            "name": {
                  "first": "George",
                  "last": "Smith"
             }
           }
}

This is my script assertion:

import groovy.json.JsonSlurper
def response=messageExchange.response.responseContent
def json=new JsonSlurper().parseText(response)

if (json.registers.name){

   def first=json.registers.name.first

   assert first!=null

}

The assertion fails as the json.registers.name.first returns null. But this shouldn't happen as there is a value for first in the response. 

When I try log.info json.registers.name I get {first=George, last=Smith}. So why do I get null when I try to get the value of the first?

All help and ideas are appreciated.

[groovyguy]

I copied your response and your groovy script assertion, and I do not get a failure for first being null. When I run it, it passes fine. I even included a statement that would fail if first was anything OTHER than "George", and it ran without issue. 

if (first != "George")
	{
		assert false;
	}

[Vivi · Accepted solution]

Hi!

Thank you for answering so fast! But what I posted was not the real response but only a mock so that I could explain what the problem was (As I cannot publish online the real response) so that didn't work for me.

Today I tried something else and it worked. Here is I used in my script:

import groovy.json.JsonSlurper
def response=messageExchange.response.responseContent
def json=new JsonSlurper().parseText(response)

if (json.registers.name){

def first=context.expand('${testStepName#Response#$[\'registers\'][\'name\'][\'first\']}')

assert first!=null

}

I can't figure out why the first script didn't work and returned null but this solution is working for me and I get the right value from the response.