Gatling JSON Generator

Update (9th July 2021) - I have recently created a better approach using Java projects, you can find and read about this here: https://bestofthetest.blogspot.com/2021/07/gatling-and-test-data-generator-pattern.html?m=1 https://github.com/matthewbretten/gatling-example-datamodel-pattern

This suite is an example to dynamically generate large amounts of JSON documents and still utilising Gatling's scenario features to control different volumes of certain data.

Prerequisites

• Maven
• Scala 2.12

Running simulations

Either run by using

mvn gatling:test

Or specify a test (if there are multiple) by using

mvn gatling:test -Dgatling.simulationClass=TestSimulation

Features

• Dynamic JSON document generation from Scala objects and classes
• Generating complex JSON with nested objects, lists and relational data (e.g. a total based on nested values from a list)
• Generating random date times
• Generating random ISO country codes
• Loading random values from a file
• Picking a random number between two values (this is default functionality in Scala 2.13 but Gatling currently only supports 2.12 so had to back port this)

Behaviour

When this code is run, it will attempt to perform POST HTTP requests to http://localhost:5000 (as I was running a local Python Flask application to test receiving the requests). As part of the POST request, it will include the generated JSON as part of the request body.

Sample data

This code will generate JSON data that looks like this as part of each request:

{
  "customer" : {
    "name" : "FkdUbOnVJLslId6RhojEaZPtDbuUTi",
    "age" : 43,
    "countryCode" : "ZM"
  },
  "totalPrice" : 219,
  "items" : [
    {
      "basketItemId" : 1,
      "description" : "Table",
      "price" : 79
    },
    {
      "basketItemId" : 2,
      "description" : "Chair",
      "price" : 99
    },
    {
      "basketItemId" : 3,
      "description" : "Knitting needles",
      "price" : 41
    }
  ],
  "dateCreated" : "2019-12-04 21:05:45"
}