writing_k6_api_tests.md

Writing K6 API Tests

Quickstart

1. Start a Grafana instance to test against:

   docker run -d --name=grafana -p 3000:3000 grafana/grafana

2. Create a K6 test:

   We're going to make a basic request to the Grafana instance and make sure it's running. K6 has support for TypeScript, so create a file called check_grafana_instance.ts with the following:

import { check } from 'k6';
import { http } from 'k6/http'

export const options = {
    scenarios: {
        api: {
          executor: 'shared-iterations',
        },
    },
};

export default function () {
    const res = http.request('GET', '<http://localhost:3000>');
    check(res, { 'status ok': res.status === 200 });
}

3. Run the tests:

   grafana-bench test \
     --service my-service \
     --service-version 1.0.0 \
     --service-url http://localhost:3000 \
     --test-runner k6 \
     --suite-name my-repo/k6 \
     --suite-path check_grafana_instance.ts

You should see output which looks like:

CI/api_test.ts ... passed

Tests executed 1
Tests passed 1
Tests failed 0
Tests error 0

Tests suite passed

Introduction

K6 tests are written in JavaScript and run in the Goja runtime. This is a small but important detail. While it looks like standard JavaScript, we don't have all of the capabilities of Node and K6 has added a few of its own.

For instance, we do not have access to writing or reading files, but we do have a super fast implementation for generating random data. Additionally K6 handles concurrency for us during load testing.