REST API testing with SpecFlowAistė Stikliūtė @ Visma Lietuva

Agenda

Why SpecFlow REST API How to

Details & tips Live demo

Bonus:other uses

of SpecFlow

Why SpecFlow• SoapUI?

• Fitnesse?

• Cucumber?

Why not…

SoapUI

Free version issues

Tests less easy to read

Thought there was no CI

Fitnesse

Works poorly with .NET

Wiki markup and tables interface is tiring

Cucumber

Yes – SpecFlow is Cucumber for .NET!

Continuous integration

BDD / Gherkin language

GIVEN book with ISBN “1-84356-028-3” is in the systemAND it’s available quantity is 9WHEN I add a book with ISBN “1-84356-028-3”THEN the book is successfully added to the listAND available qty. for book with ISBN “1-84356-028-3” is 10

The environment

Same tool as for GUI

tests (Visual Studio, C#)

Same solution as GUI tests and even the whole

system

Convenient!

Developers are

integrated!

Rest API• What it is

• Examples

• Why test it

REST API

Web architectural style with a set of constraints

Web service APIs that adhere to the constraints - RESTful

Frontend

Backend

REST APIExternal

system(s)External system(s)

Rest API: typically used HTTP methods

Resource GET PUT POST DELETE

Collection URI,such as http

://example.com/resources

Listcollection's members

Replacecollection with another collection

Create new entry in the collection

Delete the entire collection

Element URI,such as http

://example.com/resources/item17

Retrievethe member of the collection

Replace the member of the collection

Not generally used

Delete the member of the collection

Example 1

Request

GET https://eshop.com/books/14765

Response

Status: 200 OK

{ "id": “14765", “title": “Game of Thrones", “author": “George R. R. Martin", “isbn": "1-84356-028-3", “availableQty": “4"}

Example 2

Request

POST https://eshop.com/books

{ “title": “501 Spanish Verbs", “author": “C. Kendris", “isbn": "1-84750-018-7", “availableQty": “10"}

Response

Status: 200 OK

{ “id": “78953“}

Example 3

Requests

DELETE https://eshop.com/book/84523

GET https://eshop.com/admin

PUT https://eshop.com/book/24552

{ [some wrong data] }

Responses

Status: 200 OK

Status: 401 Unauthorized

Status: 500 Internal Server Error

Why test Rest API?

If used by external applications: this is your UI!

As your system layer: Can help find / isolate problems:

Security

Performance

Robustness

Functionality

May be more simple to test / automate than GUI tests

How to……write tests

Step 1: know what your API should do

Documentation

Talk to developers

Browser’s Developer tools

REST client (e.g. Postman on Chrome)

Dev tools + REST client

Step 2: write your test scenarios

ListBooks.feature

Scenario: There are no books in the systemGiven there are no books in the systemWhen I retrieve list of all booksThen I get empty list

Scenario: There are less books than fit into 1 pageScenario: There are more books than fit into 1 pageScenario: Sort booksScenario: Search for a book

Step 3: generate scenario steps

[Given(@”there are no books in the list”)]public void GivenThereAreNoBooksInTheList(){

ScenarioContext.Current.Pending();}

Step 4: implement scenario steps

Here‘s where the Rest API calls go!

Plain C# can be used or libraries // I use RestSharp

Structure your project

Project structure

Features: all features, can have subfolders

Steps: bindings of features to actions

Actions: where things happen

Helpers: among others, RestHelper.cs

Model: classes matching our API data format

App.config: holds base URI

A quick look into code: Steps & ActionsSteps

Actions

A quick look into code: Model

A quick look into code: RestHelper.cs

Step 5: run tests

Step 6: add to Continuous Integration

Details & Tips

Hooks (event bindings)

Before / after test run static

Before / after feature static

Before / after scenario

Before / after scenario block (given / when / then)

Before / after step

Step scope and reusing

Steps are global! Naming: “when I update it” “when I update the book”

Scoped bindings:

[Scope(Tag="my tag", Feature=“my feature", Scenario=“my scenario")]

Reusing step in other steps

[Given(@"(.*) is logged in")]public void GivenIsLoggedIn(string name) { Given(string.Format("the user {0} exists", name)); Given(string.Format("I log in as {0}", name));}

Table and multiline step arguments

Live Demo

BonusOther uses of SpecFlow

Behaviour /Business Driven Development

1. PO / QA writes scenarios

2. Developer writes unit/integration tests

3. Developer writes code until tests pass

BDD

Driving Selenium tests

Scenario: Successful loginGiven I am in login pageWhen I login with correct

credentialsThen I am redirected to main page

Scenario: Successful loginGiven I am at http://eshop.com/loginWhen I login with user “John” and password

“Password1”Then I am redirected to http://eshop.com/main

SpecFlow & Seleniumusing scoped bindings

[When(@"I perform a simple search on '(.*)'", Scope(Tag = “api"))]public void WhenIPerformASimpleSearchOn(string searchTerm) {

var api = new CatalogApi();actionResult = api.Search(searchTerm);

}

[When(@"I perform a simple search on '(.*)'"), Scope(Tag = "web")]public void PerformSimpleSearch(string title) {

selenium.GoToThePage("Home"); selenium.Type("searchTerm", title);

selenium.Click("searchButton");}

Test case management / Test reporting

One functional test suite? Manual

Automated API

Automated GUI

One report with test list that can be read by POs and manual QAs

management

customer

Thank you!Time for questions