apickli - REST API integration testing framework with cucumber.js

Apickli is a REST API integration testing framework based on cucumber.js.

It provides a gherkin framework and a collection of utility functions to make API testing easy and less time consuming.

Apickli is also available as an NPM package.

Cucumber.js is JavaScript & Node.js implementation of Behaviour Driven Development test framework - Cucumber. Cucumber.js is using Gherkin language for describing the test scenarios in BDD manner.

How to start - a simple tutorial

Start new project

Below steps will help you start a new test project from scratch.

1. Folder structure

Let's start a new integration testing project for an API called myapi. The folder structure will need to match the structure expected by cucumber.js:

test/
---- features/
--------- step_definitions/
-------------- apickli-gherkin.js
--------- support/
-------------- init.js
--------- myapi.feature
---- package.json

Features directory contains cucumber feature files written in gherkin syntax. step_definitions contains the JavaScript implementation of gherkin test cases. Check out the GitHub repository for example implementations covering most used testing scenarios.

2. Package.json

This can be an example package.json file for our project:

{
	"name": "myapi-test",
	"version": "1.0.0",
	"description": "Integration testing for myapi v1",
	"dependencies": {
		"apickli": "latest"
	}
}

3. Install dependencies

Now we can get the project dependencies installed:

$ npm install

4. Scenario definitions

Let's start with the scenario file called myapi.feature. For more examples of feature and scenario definitions, check out test folder.

Feature:
	Httpbin.org exposes various resources for HTTP request testing
	As Httpbin client I want to verify that all API resources are working as they should

	Scenario: Setting headers in GET request
		Given I set User-Agent header to apickli
		When I GET /get
		Then response body path $.headers.User-Agent should be apickli

5. Get apickli-gherkin steps

We now need the corresponding step definitions that implement the steps in our scenario. Apickli has a collection of steps already implemented - ready to be included in your project - see gherkin expressions.

The simplest way to adopt these expressions is to create a file named apickli-gherkin.js in features/step_definitions and import the apickli/gherkin.js module.

Add the following to test/features/step_definitions/apickli-gherkin.js

module.exports = require('apickli/apickli-gherkin');

6. Support code

Now we need a support code to implement cucumber hooks and initialize apickli. Add the following in features/support/init.js:

'use strict';

const apickli = require('apickli');
const {Before} = require('@cucumber/cucumber');

Before(function() {
    this.apickli = new apickli.Apickli('http', 'httpbin.org');
    this.apickli.addRequestHeader('Cache-Control', 'no-cache');
});

7. Run tests with cucumber.js

The following will run our scenario (in the project directory):

$ cucumber-js features/myapi.feature
....

1 scenario (1 passed)
3 steps (3 passed)

Step timeout

Cucumber.js default step timeout is 5000ms. Add the following to features/support/init.js in order to change it:

setDefaultTimeout(60 * 1000); // this is in ms

Gherkin Expressions

The following gherkin expressions are implemented in apickli source code source/apickli/apickli-gherkin.js:

GIVEN:
	I set (.*) header to (.*)
    	I set cookie to (.*)
	I set body to (.*)
	I pipe contents of file (.*) to body
	I have basic authentication credentials (.*) and (.*)
	I set bearer token
	I have (.+) client TLS configuration
	I set query parameters to (data table with headers |parameter|value|)
	I set headers to (data table with headers |name|value|)
    	I set form parameters to (data table with headers |parameter|value|)

WHEN:
	I GET $resource
	I POST to $resource
	I PUT $resource
	I DELETE $resource
	I PATCH $resource
	I request OPTIONS for $resource

THEN:
	response code should be (\d+)
	response code should not be (\d+)
	response header (.*) should exist
	response header (.*) should not exist
	response header (.*) should be (.*)
	response header (.*) should not be (.*)
	response body should be valid (xml|json)
	response body should contain (.*)
	response body should not contain (.*)
	response body path (.*) should be (.*)
	response body path (.*) should not be (.*)
   	response body path (.*) should be of type array
   	response body path (.*) should be of type array with length (\d+)
   	response body should be valid according to schema file (.*)
   	response body should be valid according to openapi description (.*) in file (.*)
	I store the value of body path (.*) as access token
	I store the value of response header (.*) as (.*) in scenario scope
	I store the value of body path (.*) as (.*) in scenario scope
	value of scenario variable (.*) should be (.*)
	I store the value of response header (.*) as (.*) in global scope
	I store the value of body path (.*) as (.*) in global scope

Setting Proxy Server

apickli uses node.js request module for HTTP communications which supports setting proxy servers via the following environment variables:

• HTTP_PROXY / http_proxy
• HTTPS_PROXY / https_proxy
• NO_PROXY / no_proxy

For more information, see https://github.com/request/request#controlling-proxy-behaviour-using-environment-variables

Variable Injection

It is possible to use Scenario Variables in a Feature file, that will have values injected when the tests are run. Whilst defining values explicitly provides better clarity to those reading a feature file, there are some configuration values such as Client Id which it is easier to externalise.

By default, backticks are use to indicate a variable in a feature file. When instantiating Apickli, a different character can be passed as a parameter. In order to follow BDD best practices, global variables should not be used in the way. Each Scenario should be independent, and as such if you would like to define configurable variables it should be done using the Before hook:

See source/test/features/injecting-variables.feature for examples.

Client Authentication

In order to make a request to a server that is protected by Mutual TLS, you must specify your client TLS configuration. This can be done when initializing Apickli as shown below.

Before(function() {
		this.apickli = new apickli.Apickli('http', 'httpbin.org');
		this.apickli.clientTLSConfig = {
				valid: {
						key: './fixtures/client-key.pem',
						cert: './fixtures/client-crt.pem',
						ca: './fixtures/ca-crt.pem',
				},
		};
});

This configuration can then be referenced using the following step definitions.

Given I have valid client TLS configuration

Contributing

If you have any comments or suggestions, feel free to raise an issue or fork the project and issue a pull request with suggested improvements.