How to find json array length in json extractor

Question

Im using the following JSON and query to calculate the array length in the JMeter json extractor.

{ "data": { "modal": "HJ", "technicalid": "e492fc62-a886-67a461b76de8", "viewModel": { "series": [ { "name": "H_0_G_0_R_0", "UID": "J_0_G_0_R_0", "description": "Test1", "type": "series", "groups": [ { "name": "H_0_G_0", "UID": "G_0_G_0", "description": "Group 1", "type": "group" } ], "postProcessing": null } ] }, "status": "success" }, "success": true, "statusCode": 200, "errorMessage": "" }

Here is the query.

data.Model.series[0].groups.length

This is working fine in the online jsonquerytool. When I use this query in the JMeter json extractor, it is returning null. I assume this is because it is returning an integer because other similar queries which are returning strings are working fine with json extractor . How to find the array length in JMeter json extractor?

Answer 1

With JSON Extractor you can provide "Match No." as -1:

and the number of matches will be available as foo_matchNr JMeter Variable:

---

Alternative option is going for JSON JMESPath Extractor which provides length() function so you can get the size of the array as:

length(data.viewModel.series[0].groups)

or if you prefer pipe expressions

data.viewModel.series[0].groups | length(@)

Answer 2

Why JSON extractor to calculate the length? You could use a post processer. Like JSR223 post processer using groovy script.

import groovy.json.*

def response = prev.responseDataAsString ;
def json = new JsonSlurper().parseText(response) ;
def sizeResultPractitioners = json.data.viewModel.series[0].groups.size();

log.info("---------->"+sizeResultPractitioners);

I tried with your JSON response payload and also tried with modified response payload,

With modified response payload,