[SOLVED] How to run a k6 script with multiple payloads using fs module?

How to run a k6 script with multiple payloads using fs module?

I'm trying to run a k6 script that uses multiple payloads stored in JSON files. I want to read these files using the fs module and send them as part of my HTTP requests. However, it seems that the fs module is not supported in k6.

I understand that k6 does not support the fs module. How can I achieve the same functionality in k6? Is there an alternative way to load multiple payloads from JSON files in k6?

Solution

You can use the open function in the init context. It's recommended to use open in combination with SharedArray to reduce memory consumption.

import { SharedArray } from 'k6/data';

const data = new SharedArray('users', function () {
  // this function *MUST* return an array:
  return JSON.parse(open('./users.json'));
});

export default function() {
  doSomething(data[0]);
}

The SharedArray can only handle arrays, as the name suggests. If your JSON file does not contain a top-level array, but something else, you have to wrap it in a singleton array (an array with a single item): return [JSON.parse(open(…))];.

There's also an expiremental fs module