Continuous Integration
- A Framework for Better Quality Software
Richmond SPIN
Richmond
Eric Pugh
May 13th, 2009
1

Who am I?
 Principal of OpenSource Connections
Contributer to CruiseControl and
Continuum CI projects
Member of Apache Software Foundation
Presenter at many conferences
including OSCON, ApacheCON, jTDS,
ExpoQA
Fascinated by the art of software
development
Continuous Integration RICHMOND, May 13, 2009
2

What are we talking about?
What is CI?
Why does it matter to me?
What do I need to use CI?
Demonstration of Hudson
Where does CI fit into the SPIN World?
Questions!
3
Continuous Integration RICHMOND, May 13, 2009
3

What is Continuous Integration?
From Martin Fowler:
“a fully automated and reproducible build,
including testing, that runs many times a day”.
http://martinfowler.com/articles/continuousIntegration.html
4
Continuous Integration RICHMOND, May 13, 2009
4

Rapid Feedback
< 10 minutos
Continuous Integration RICHMOND, May 13, 2009
5

How is CI important to different members of a team?
6
Continuous Integration RICHMOND, May 13, 2009
6

Life of a programmer without CI...
 Unstable code, integration is difficult
Many build errors reported
Only one person on the team can build the entire
project
Demonstrations require extensive planning
Feedback cycle is long
Every day is a struggle to be productive
7
Continuous Integration RICHMOND, May 13, 2009
7

Life of a programmer with CI...
 The build process is simple and repeatable
Elimination of Human Error
Demo’s are quick and easy
Feedback cycle is very rapid
Every day you know you can code!
8
Continuous Integration RICHMOND, May 13, 2009
8

For a tester
control

 What is in the build?
 What has changed between builds?
 How do I verify functionality?
9
Continuous Integration RICHMOND, May 13, 2009
9

For a Project Manager
Visibility

10
Continuous Integration RICHMOND, May 13, 2009
10

For a Project Manager
11
Continuous Integration RICHMOND, May 13, 2009
11

For a development team
security

12
Continuous Integration RICHMOND, May 13, 2009
12

For a development team
13
Continuous Integration RICHMOND, May 13, 2009
13

For a development team
14
Continuous Integration RICHMOND, May 13, 2009
14

For a development team
15
Continuous Integration RICHMOND, May 13, 2009
15

What is needed to get started?
A dedicated machine
Source Control
Automated Build Script
Method of notification
16
Continuous Integration RICHMOND, May 13, 2009
16

What are the challenges to using CI?
17
Continuous Integration RICHMOND, May 13, 2009
17

Challenge One: Cultural Change
 CI needs a champion who acts as the ambassador to the leaders of the
organization.
Thought leaders in the organization who can help encourage
developers to accept the process changes that CI brings
 A very successful test case
¿A greenfield project if possible?
18
Continuous Integration RICHMOND, May 13, 2009
18

Challenge Two: Environmental Difficulties
 All the tests should be true unit tests, not
integration tests
 Few or no external dependencies
 A beefy build server...
 A strategy for deploying code into the CI
environment
Database changes are SIMPLE
19
Continuous Integration RICHMOND, May 13, 2009
19

Challenge Three: Project Characteristics
Fewer branches to the code makes life easier
Many small code changes. Code is committed throughout the day.
There are good unit test coverage.
The code is ready for deployment, not in pieces.
20
Continuous Integration RICHMOND, May 13, 2009
20

Challenge Four: Stability of CI Tool
X
The CI system must be as well maintained as
the Source Control system.
The CI system performs builds very quickly.
Who has responsibility for CI? It’s very
important to have a “throat to choke”.
No false alarms. If there are false alarms
then the developers lose confidence in the CI
✓
system.
21
Continuous Integration RICHMOND, May 13, 2009
21

Demo of Hudson
22
Continuous Integration RICHMOND, May 13, 2009
22

Where does CI fit into the SPIN World?
23
Continuous Integration RICHMOND, May 13, 2009
23

CI Maturity Model?
Fewer branches to the code makes life easier
Many small code changes. Code is committed throughout the day.
There are good unit test coverage.
The code is ready for deployment, not in pieces.
http://www.anthillpro.com/blogs/anthillpro-blog/2009/05/05/1241542860000.html
24
Continuous Integration RICHMOND, May 13, 2009
24

Virtuous Circle?
Metrics are hard to get
Developers rebel against on high management
Need good processes that support and encourage other good
processes
25
Continuous Integration RICHMOND, May 13, 2009
25

HackyStat
26
Continuous Integration RICHMOND, May 13, 2009
26

Test Automation
CI increases the rewards for doing test automation
unit
integration
functional?
system?
27
Continuous Integration RICHMOND, May 13, 2009
27

Where to next?
 Continuous Integration: Improving Software Quality
and Reducing Risk
CITConf is the conference for CI. This year it was
April 24, 25 in Minneapolis, MN.
Take a handout with reference links!
28
Continuous Integration RICHMOND, May 13, 2009
28

Matrix of 22 differences in CI systems
http://confluence.public.thoughtworks.org/display/CC/CI+Feature+Matrix
29
Continuous Integration RICHMOND, May 13, 2009
29

Why CI?
Eliminate human errors
Tests that run frequently are more valuable
A CI system is the foundation of a project status dashboard
Eliminate integration problems!
30
Continuous Integration RICHMOND, May 13, 2009
30

RICHMOND
Eric Pugh epugh@opensourceconnections.com
May 13th, 2009
31