JMeter - Extract value from JSON response and update variable

Question

My goal is to create a Google Drive CRUD with JMeter. I was able to upload files with proper OAuth configuration.

However, I am struggling in extracting the response data to be used in further HTTP Requests.

The response of the upload is this simple JSON:

{
 "kind": "drive#file",
 "id": "blablabla",
 "name": "Untitled",
 "mimeType": "text/plain"
}

I would need to fetch this id in a PostProcessor component and update a JMeter variable with this value. This way I could reference to this value in the Read, Update and Delete requests.

I've tried to use the JSON Extractor and BeanShell, but I was unsucessful.

Answer 1

If you want to extract this id value into a JMeter Variable the relevant Json Path query would be as simple as:

$.id

You can verify this yourself using JSON Path Tester mode of the View Results Tree listener

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So if you add a JSON Extractor as a child of the request which returns the above JSON and configure it like:

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JMeter will store it into id variable as it evidenced by the Debug Sampler:

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Going forward you should be able to access this value as ${id} where required:

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More information: API Testing With JMeter and the JSON Extractor