Jmeter : How to extract first element from json array

debugcn 投稿 Dev

Sachetan

I am trying to extract first element from a json array. Below mentioned is json array

   [
    {
        "cohortDefinition": {
            "Key": 1151,
            "id": 1798,
            "srcId": "3526",
            "pcKey": -1,
            "userName": "CHROME_USER",
            "name": "JMeter2017-01-06-1483749546167",
            "Type": "SUBJECT",
            "tool": "CB",
            "count": 32757,
            "extractionStatus": "",
            "dateCreated": "2017-05-10T17:48:45Z"
        },
        "datasource": {
            "id": 2,
            "name": "health",
            "subjectCount": 116352
        },
        "project": {
            "id": 747,
            "name": "Jmeter Project"
        }
    },
    {
        "cohortDefinition": {
            "Key": 1150,
            "id": 1796,
            "srcId": "3525",
            "pcKey": -1,
            "userName": "CHROME_USER",
            "name": "JMeter2016-10-27-1477620919644",
            "Type": "SUBJECT",
            "tool": "CB",
            "count": 32757,
            "extractionStatus": "",
            "dateCreated": "2017-05-10T16:57:11Z"
        },
        "datasource": {
            "id": 2,
            "name": "health",
            "subjectCount": 116352
        },
        "project": {
            "id": 747,
            "name": "Jmeter Project"
        }
    }
]

From above json i would like to extract first value ie. srcId": "3526". I tried doing following expression in Jmeter extractor

$..cohortDefinition.srcId[1]

However it is not working. If anyone know how to do this please do let me know.

NaveenKumar Namachivayam

After JMeter 3.0, you can use JSON Extractor, see:

https://stackoverflow.com/a/47043204/460802

Before JMeter 3.0:

Please follow the below steps to retrieve srcId.

Add a JSON Path Extractor to your request and configure below values.

Destination Variable Name - myVar

JSON Path Expression - $..cohortDefinition.srcId - this will extract all the srcIDs from the JSON.

Default Value - Not Found or Err