Battle for Code Quality - A Story of One Java Project

©2015 GlobalLogic Inc.


Battle for Code Quality Story of One Java Project

Ilya TsvetkovDec 2015, Krakow

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Few words about speaker

• I enjoy doing Java development since year 1999, 10+ years I lead teams on their road to successful delivery of products that makes customer happy

• I’m big fan of Agile and XP, although I started as RUP trainer back in 2000

• Yes, I can remember Java 1.2, EJB 1.1 and TopLink 1.0

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Quality

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Good code makes you feel good when you read it

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Before we start…

• 5 locations (USA, Ukraine, India) with team of 100+ members

• Java backend + 3 clients (iOS, Android, Web)

• Backend built with JPA, Spring, REST API

• > 10 releases in 3 years, 50+ enterprise customers worldwide

What kind of project we are talking about?

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Looks quite standard for today’s outsourcing industry!

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Quality pyramid

Manual tests

UI Acceptance tests

Integration tests

Unit tests

• More unreliability• Greater cost (harder to automate)• Slower feedback

The higher we go:

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Sad but true

Unit tests

Integration tests

UI Acceptance tests

Manual tests

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Quality: who is in charge?

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Manual tests

UI Acceptance tests

Integration tests

Unit tests

What teams build software quality?

Develo

pmen

t

team

Auto

mat

ion

team

Test

team

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Quality: what it takes to inject into development process

• Build system + Dependency management

• Continuous Integration & Delivery• Test automation on CI• Code Quality Standard

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Continuous Integration tests vs Continuous Delivery tests

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Continuous Integration tests vs Continuous Delivery testsContinuous Integration

Watch code

Build

Unit Tests

Publish results

Continuous Integration and Deployment

Watch code

Build

Unit Tests

Automatic Deployment

Functional tests

Performancetests

Publish results

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What are your tests?

Data Access Layer (JPA)

Business Logic (Services)

Presentation (REST)

Providers (Connectors)

Java Unit tests

Java Integration

tests

SOAP UI tests

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Unit tests

• Is there a developer in this room who doesn’t develop unit tests?

• Unit tests today are as common as regular code of your app

• What else can we say about them?

Test classes and methods in isolation

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I want coverage, man

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What is always green test?

What is

Typical Unit test:

−Verify test results

−What Feature is tested−Fixture Setup−Call feature that is tested (“Stimulus“)

Count test antipatterns here

Can you see steps?

What about Verify step?

Unit test #1 wtf

wtf

wtf

feature

fixture setup

stimulus

What about Stimulus?

Unit test #2

feature

fixture setupverify

Unit test #3

feature

verify

Unit test #4feature

fixture setup

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“Always green” unit test

• It counts in all reports for unit tests

• Management receives nice reports about coverage

• Never fails: “A test that never fails is worse than having no test at all”

• A lot of WTFs

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Can we fight “always green” tests?

• Code reviews (yep, let’s talk about them a bit later)

• Kill mutants!• Stop using Java for unit

tests! Image

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Unit test (nice one)

feature

fixture setup

stimulus

verify

BDD style: test is no longer a piece of code that only developer can understandTest is human readable executable specificationLet DSL and BDD empower your tests

Spock test

feature

fixture setup

stimulus

verify

− Easy to learnIf you know Java and JUnit, you are almost ready to go.

− Powered by GroovyJava's dynamic companion lets you do more in less time. Plus, it's a lot of fun!

− Eliminates wasteNo assertion API. No record/replay mocking API. No superfluous annotations.

− Compatible with JUnit− Open-minded

Test-first? Test-last? Unit-level? Integration-level? Test-driven? Behavior-driven? We believe there are many ways to create good software, and try to give you the flexibility to do it your way.

− Beautiful languageExpress your thoughts in a beautiful and highly expressive specification language.

Why Spock

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Dev Integration tests


Business Logic (MyIT Services)

Presentation (REST)

MyIT providers

Java Unit tests

Java Integration

tests

SOAP UI tests

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Integration test: JPA layer

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Integration test: Service layer

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REST API tests


Business Logic (MyIT Services)

Presentation (REST)

MyIT providers

Java Unit tests

Java Integration

tests

SOAP UI tests

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REST API tests

• In servlet container or not?

• With Java or not?

• Plain Apache HttpClient?

• Jersey Test framework?

• Spring MVC Test framework and its RestTemplate?

Who runs tests on REST API? What tool do you use? Do you run it on CI?

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Our choice: SmartBear SOAP UI

• REST API is Java agnostic so no need for Java here

• REST tests could be developed by QA team, not only by Dev team

• Same tests can be used for Load tests and Security tests

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REST API tests runtime

• Embedded Servlet container - Jetty

• Embedded database HSQLDB

• Test xml datasets with DbUnit

• Tests executed on Jenkins with Maven SOAP UI plugin

• Coverage collected by Jacoco and published to SonarQube portal

Remember tests run on Jenkins

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− Java code analysis tools: PMD, CheckStyle, FindBugs, etc

− Continuous Code Inspection with SonarQube:− Tests coverage− Coding rules violations− LCOM4 (Lack of Cohesion of Methods)− Cyclomatic complexity− Total quality index− etc


Continuous Code InspectionBMC KIEV LAB: MYIT TEAM – Best practices

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Code quality standard

Publish it on project WIKI

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What is missing?

• Let SonarQube analysis be part of developer’s IDE

• Let SonarQube analysis be part of CI• Fail the build if SonarQube is unhappy• Code reviews

Add some salt before serving it to team (or to your customer)

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Let SonarQube analysis be part of developer’s IDE

• SonarLint plugin (IntelliJ IDEA, Eclipse)

• SonarQube Community plugin (IntelliJ IDEA)

• SonarQube plugin (IntelliJ IDEA, Eclipse) - commercial

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Let SonarQube analysis be part of CI• All CI servers have SonarQube plugins

• Maven/Gradle have SonarQube plugin

• Run SonarQube analysis with CI on daily basis

• Setup SonarQube notifications to make developers react!

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Fail the build if SonarQube is unhappy• Sonar Quality Gate – simply makes indication on portal

• Why failing the build? Because developers cannot ignore this. Try it • Sonar Build Breaker plugin – deprecated

• Some commercial alternatives available

• Develop your plugin – this is simple!

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…and finally – Code reviews

• Both are manual check of quality• Expensive and slow to run• Unreliable (depend on human being)• Feedback is not instant• Can be pain if process is bad

Code reviews vs Manual tests

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• Both educate team members during execution

• Knowledge sharing• Both find quality problems that tools cannot

find• Fun if process is good

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Make your code reviews fun

• If you are not small collocated team – use tool support!

• No tests – no review• Do not run code reviews if SonarQube is

unhappy• Use your code quality standard!• Show love to your code

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Ilya TsvetkovTeam Lead+380(50)334-24-24 [email protected]

Thank you

Engineering

Battle for Code Quality - A Story of One Java Project