Load Testing APIs with Artillery

October 4, 2020 • APIs, Testing • Published By Josh • 3 minute read

Artillery is a modern, powerful & easy-to-use load testing and functional testing toolkit. It can be used to ship scalable backends, APIs & services that stay performant and resilient under high load. Let’s learn how to use Artillery!

System Requirements
Installation
Key Concepts
Environments
Test Definition Examples
Run A Test

System Requirements

Artillery should run on any system that uses Node.js version 12 or above.

Installation

Run the following command to install Artillery globally:

npm install -g artillery

Key Concepts

Write a test definition and Artillery will run it. It’s as simple as that! Test definitions are written as YAML files and they have two main parts:

Configuration
- Define the apis you’re going to call
- Define how many users to generate over a period of time
- Define data to use in the test
- Define plugins to use
Scenarios
- Define one or more actions the user will take during the test

Environments

As part of your configuration, you can define different environments. For example, a DEV environment may have different example data to use or a different api to call compared to a production environment. This helps you customize the test per environment.

config:
  environments:
    dev:
      DEV_CONFIGURATION_HERE
    prod:
      PROD_CONFIGURATION_HERE

Test Definition Examples

Create 1 virtual user (arrivalRate) every second for 5 seconds (duration) making requests to https://pokeapi.co/api/v2/pokemon/pikachu.

config:
  target: 'https://pokeapi.co/api/v2'
  phases:
    - duration: 5
      arrivalRate: 1
scenarios:
  - flow:
    - get:
        url: '/pokemon/pikachu'

Create 1 virtual user (arrivalRate) every second for 5 seconds (duration) in a loop based on the pokemon variable.

config:
  target: 'https://pokeapi.co/api/v2'
  phases:
    - duration: 5
      arrivalRate: 1
  variables:
    pokemon:
      - ['pikachu', 'mewtwo', 'charizard']
scenarios:
  - flow:
    - loop:
      - get:
          url: '/pokemon/{{ $loopElement }}'
      over: pokemon

Create 1 virtual user (arrivalRate) every second for 5 seconds (duration) making requests to https://pokeapi.co/api/v2/pokemon/pikachu. Using the result of the first request, get a value to make the next request.

config:
  target: 'https://pokeapi.co/api/v2'
  phases:
    - duration: 5
      arrivalRate: 1
scenarios:
  - flow:
    - get:
        url: '/pokemon/pikachu'
        capture:
          json: '$.species.url'
          as: 'species'
    - get:
        url: '/{{ species }}'

Run A Test

Let’s say you saved your test definition as get-pikachu.yml. To run a test, run the following:

artillery run get-pikachu.yml

If you have environments set up and want to run the test for a specific environment, include the environment flag along with the environment name. For example, if I wanted to run the test for an environment called dev, I would run:

artillery run -e dev get-pikachu.yml

About the Author

Josh

Front End Developer

https://nightwolf.dev