Introduction to using SpecFlow tool for testing REST API. For beginners that are at least a bit familiar with test automation, and gives some details and hints.

1. REST API testing with
SpecFlow
Aistė Stikliūtė @ Visma Lietuva

2. Agenda
Why SpecFlow REST API How to
Details & tips Live demo
Bonus:
other uses of
SpecFlow

3. Why SpecFlow
• SoapUI?
• Fitnesse?
• Cucumber?

4. 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!

5. Continuous integration

6. BDD / Gherkin language
GIVEN book with ISBN “1-84356-028-3” is in the system
AND it’s available quantity is 9
WHEN I add a book with ISBN “1-84356-028-3”
THEN the book is successfully added to the list
AND available qty. for book with ISBN “1-84356-028-3” is 10

7. 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!

8. Rest API
• What it is
• Examples
• Why test it

9. REST API
 Web architectural style with a set of constraints
 Web service APIs that adhere to the constraints - RESTful
Frontend
REST API
Backend
External
system(s)
External
system(s)

10. Rest API: typically used HTTP methods
Resource GET PUT POST DELETE
Collection URI,
such as
http://example.com/res
ources
List
collection's
members
Replace
collection with
another
collection
Create new
entry in the
collection
Delete the
entire
collection
Element URI,
such as
http://example.com/res
ources/item17
Retrieve
the member
of the
collection
Replace the
member of the
collection
Not generally
used
Delete the
member of the
collection

11. 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"
}

12. 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“
}

13. 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

14. 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

15. How to…
…write tests

16. Step 1: know what your API should do
 Documentation
 Talk to developers
 Browser’s Developer tools
 REST client (e.g. Postman on Chrome)

17. Dev tools + REST client

18. Step 2: write your test scenarios
 ListBooks.feature
Scenario: There are no books in the system
Given there are no books in the system
When I retrieve list of all books
Then I get empty list
Scenario: There are less books than fit into 1 page
Scenario: There are more books than fit into 1 page
Scenario: Sort books
Scenario: Search for a book

19. Step 3: generate scenario steps
[Given(@”there are no books in the list”)]
public void GivenThereAreNoBooksInTheList()
{
ScenarioContext.Current.Pending();
}

20. 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

21. 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

22. A quick look into code: Steps & Actions
Steps
Actions

23. A quick look into code: Model

24. A quick look into code: RestHelper.cs

25. Step 5: run tests

26. Step 6: add to Continuous Integration

27. Details & Tips

28. 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

29. 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));
}

30. Table and multiline step arguments

31. Live Demo

32. Bonus
Other uses of SpecFlow

33. Behaviour /
Business Driven Development
1. PO / QA writes scenarios
2. Developer writes unit/integration tests
3. Developer writes code until tests pass

34. Driving Selenium tests
Scenario: Successful login
Given I am at http://eshop.com/login
When I login with user “John” and password “Password1”
Then I am redirected to http://eshop.com/main
Scenario: Successful login
Given I am in login page
When I login with correct credentials
Then I am redirected to main page

35. SpecFlow & Selenium
using 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");
}

36. 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

37. Thank you!
Time for questions 