1. Building .NET
Applications with BDD
NDC 2011
GASPAR NAGY
gn@techtalk.at
Twitter: @gasparnagy
JONAS BANDI
jonas.bandi@techtalk.ch
Twitter: @jbandi
Oslo, 8. June 2011
COPYRIGHT 2011, TECHTALK - WWW.TECHTALK.CH

2. TechTalk at a glance
• Established: 1993
• Branches: Austria, Hungary, Switzerland
• 3 Managing partners: no external owners
• Employees: ~ 60 employees
• Turnover 2010: ~ 7 Mio CHF
• Risk rating: very low risk
• Self-financing, healthy growth
TechTalk office, Vienna/Austria
COPYRIGHT 2011, TECHTALK - WWW.TECHTALK.CH

3. Background
• At TechTalk we are trying to live a BDD
process for several years
• We started SpecFlow in 2009 out of a
need to implement BDD
• We have implemented and improved
our BDD process and knowledge in
many projects
• … we are still learning The research is partially supported by the
project of Eötvös Loránd University:
TÁMOP-4.2.1.B-09/1/KMR-2010-0003
3

4. BDD – A definition from Dan North
BDD is a second-generation,
outside-in, pull-based, multiple-
stakeholder, multiple-scale, high-
automation, agile methodology.
It describes a cycle of
interactions with well-defined
outputs, resulting in the delivery
of working, tested software that
matters. Dan North, Agile Testing, Specifications and BDD Exchange 2009
4

5. The BDD Development Process
… how we live it
Requirements Analysis
Executable & Automated
Specifications
Improving Feedback with a
Transparent Development Process
Living Documentation
5

6. Requirements Analysis & Colaboration
We want to encourage new users to place an order.
Therefore we are going to offer 10% discount on
every initial order.
Register as “bart_bookworm”
Go to “/catalog/search”
Enter “ISBN-0955683610”
Click “Search”
Click “Add to Cart”
Click “View Cart”
Verify “Subtotal” is “$33.75”
public void CalculateDiscount(Order order)
{
if (order.Customer.IsNew)
order.FinalAmount = Math.Round(order.Total * 9/10);
}
6

7. Capturing and Organizing
Requirements
DEMO
Your Product Backlog is more than just a list!
www.speclog.org
7

8. Outcome of Requirements Analysis
• Sprint Planning
•User Stories
•Acceptance Criterias
•… illustrated by Examples
8

9. Executable & Automated
Specifications
Requirements Analysis
Executable & Automated
Specifications
Improving Feedback with a
Transparent Development Process
Living Documentation
9

10. Automation
• Why?
• iterative & incremental
development demand a
continuous feedback
• Challenges
• Abstraction vs. Reliability
• Trust
• Shared Understanding
• Effort
10

11. Scenarios: Automating Examples
• Some Formality is needed
•But: Keep it „business readable“
• Gherkin
11

12. 40 Spoken Languages
12

13. Writing Maintainable Scenarios
Specification by Example
by Gojko Adzic
13

14. Scripts vs. Declarative Scenarios
Given a clear database
And the database is loaded from "sample-data.sql"
And the webserver is running
When I go to URL: http://localhost:8080/myapp
And I click the "Login" link
And I enter username: john
And I enter password: john99
And I click the "Login" button
Then the page contains text: Hello John!
Background:
Given the following users:
| First Name | Last Name |
| John | Smith |
When John logs in
Then a greeting "Hello John!" is displayed.
14

15. Decouple, Reduce Noise, Focus on
Value
Given a clear database
When I create a user "John Smith" with login "jsmith"
When I login as "jsmith"
Then a greeting "Hello John!" is displayed.
Background:
Given the following users:
| First Name | Last Name |
| John | Smith |
When John logs in
Then a greeting "Hello John!" is displayed.
15

16. Automation on Different Levels
16

17. Challenges of UI Automation
• Technical
•Infrastructure Dependency (Speed, Stability …)
•Tests run in another Process
• Development Process
•80% of all changes are in the UI
• Tools can help:
•Mara, MVCContrib (“Capybara like”)
17

18. Organization of Features
Features are TODO: Screenshot
project artifacts:
•versioned in VCS
•Hierarchies
•Change over time TODO: Screenshot
18

19. Organizing Steps
• Steps are code
• Organize steps along domain
concepts. Avoid feature-
coupled steps
• Scoped steps
19

20. Organizing Steps
• Application Driver Layer
•Abstraction
•Functional composition
•Reuse
20

21. Outside-In Development
• Starting from the UI Layer is
difficult
•Start with a scribble / sketch
•Good conventions help (aka.
semantic markup) 1
•Progress step by step. Building 2
3
the UI incrementally 4
5
• Progressing to TDD
•Not always needed?
21

22. Improving Feedback with a
Transparent Development Process
Requirements Analysis
Executable & Automated
Specifications
Improving Feedback with a
Transparent Development Process
Living Documentation
22

23. Transparency
• Why?
•Trust, Feedback, Learning, Embracing Change
• Scrum Tools
•Standup, Taskboard, Burndown, Demo,
Retrospective
• How can BDD help to improve it?
•Technical Feedback
•Different Perspective
•Shared understanding
23

24. The Project
Dashboard
DEMO
24

25. Build Server Integration
• Generating Reports
• Using Tags
• Demo: Build Config
25

26. Using Tags
31

27. Living Documentation
Requirements Analysis
Executable & Automated
Specifications
Improving Feedback with a
Transparent Development Process
Living Documentation
32

28. Evolving the living documentation
Product Backlog Living Documentation
AccCrit 1 AccCrit 1
User Story 1
AccCrit 2 „Done“ AccCrit 2
Feature 1
AccCrit 3 AccCrit 3
User Story 2
AccCrit 4 AccCrit 5
AccCrit 5 AccCrit 4
User Story n Feature n
AccCrit m AccCrit m
• Units of work • Documentation
• Organized according to • Organized according to
priority/value/effort functionality/overview
• Versioned/maintained with
source code
33

29. Living documentation
Current sprint Features “done”
merge
when F
Sprint US accepted
US
Backlog AC F F
Acceptance
Criteria AC
US Acceptance
refine
AC
Criteria AC
AC
Acceptance the F F F
Criteria
US specification AC
Acceptance
Criteria
Acceptance
Criteria
F F
Acceptance
US Criteria
Acceptance AC AC
Criteria Given … {…} validate
Automation
AC AC
When … {…} continuously
AC living documentation
Then … {…}
specification with examples
validate
executable continuously
specification
34

30. Living Documentation: Feature Tree
35

31. Pushing Living Documentation
further
DEMO
36

32. Other BDD Sessions at the NDC
Thursday Morning:
• Gojko Adzic
• Scott Bellware
37

33. Questions &
Discussion
GASPAR NAGY JONAS BANDI
gaspar.nagy@techtalk.at jonas.bandi@techtalk.ch
Twitter: @gasparnagy Twitter: @jbandi
COPYRIGHT 2011, TECHTALK - WWW.TECHTALK.CH