All Builds Are Good With Continuous Integration Presented by: Scott Bateman Houston TechFest – August 25 th, 2007

Underlying Philosophy “Continuous Integration doesn't get rid of bugs, but it does make them dramatically easier to find and remove.” -- Martin Fowler

There are Many Horror Stories  Many software projects have deficiencies around builds and deployment. No concrete knowledge what is in compiled executables Heavy dependency on a single individual Inability to reproduce or change prior builds (bug fix) No capability to produce immediate builds Risk of bad check in losing many productive hours  Code integration for projects used to take days  BuildMaster can be a full time job Quorum Experience evolved based on needs

We Learn From Experience  Software Industry Changes Rapidly 15 years ago (1992) – Windows 3.1 released Microsoft ships Visual Basic v2.0 and introduces Access In 1992… Internet Information Server (IIS) and Active Server Pages (ASP) don’t exist No image has ever been seen on Internet… just text 12 years ago (1995) – Java is announced by Sun JavaScript announced by Netscape, SourceSafe released Internet becomes widely used, IE 1.0 released 10 years ago (1997) –Intel Releases Pentium II (233, 266 & 300 MHz) IE 4.0 released, PVCS released SQL Server 6.5 launches Microsoft attack on Oracle 5 years ago (2002) –Windows XP, iPod and Xbox all hit the market.NET 1.0 released, NUnit released 2 years ago (2005) – CruiseControl.NET, NAnt released.NET 2.0 released, IE 6.0 was the latest version

Build Upon Past Successes  Just 15 years ago, this was your Windows desktop (Windows 3.0)  Continuous Integration is bound to become as common as using a source control repository

Reaping the Benefits  To benefit from this rapid change, projects must analyze available tools and methodologies  CruiseControl.NET and NAnt have been around since about 2005, NUnit is older  Although it will take some time to convert existing projects, it will be worth it  All new projects should consider using Continuous Integration (CI)

Why Use Continuous Integration?  Less time spent on builds/deployment  Lower risk of error as operations are scripted  Early notification of errors  Easy to revert to bug-free state  Constant availability of latest executables  Shorter feedback cycles  Let’s you focus on real problems, not mechanics  Makes your boss happy – saves time and $$$

Goal is to have CRISP Builds  C – Complete All components consolidated in push-button build  R – Repeatable Ability to re-generate any previous build  I – Informative Communicate pertinent information to stakeholders  S – Schedulable Must support mechanism to run unattended  P – Portable Can be run on any machine

Test Deploy Layers of Continuous Integration Monitor Build Integrate Notify Build Source Control Deployed Executable NotifyDeploy A U T O M A T E D M A N U A L Potential for Human Error

Source Control  Repository Should Contain All source code Baseline configuration files Resources and images Database scripts and code Report templates Documentation  Repository Should Not Contain Output binaries “everything you need to do your build, but not results”

Source Control  No matter what tool you choose, it is recommended to Label before any builds or major events Only check out the files you are currently working on Only check files out for a few days at a time.  If you use Microsoft SourceSafe Use the latest version of VSS Don’t use VSS and Visual Studio at the same time read more:

 Commit Builds Occur every time a change is committed Catch compile time problems Should be kept fast ­10 minutes is a good goal ­Should not take more than 1 hour Monitoring devices make it fun Allows everyone to develop with confidence Should have dedicated machine ­Can be switched easily (Portable) Monitor (CruiseControl.NET) Demo

Real-Time Status  Use monitoring devices, Web Dashboard and/or CCTray to communicate the real-time status of your build Best Practice

Integrate (NAnt)  Secondary Builds Catch run time problems Include more elaborate testing Static code analysis (FxCop) Operations that may be slower such as DB access In-depth validation of application May not be needed ­If full build/deploy is < 1 hour Kicked off by Commit Build or scheduled (daily)

Notifications  Secondary builds executed daily and send detailed to interested parties Best Practice

Integrate (NAnt)  Release (“Official”) Builds Label repository Update application version Publish results ­ / Text Message ­RSS (can replace Visual Studio start page) ­Web page Update bug tracking tool Create installer/DVD Deploy to testing environment/FTP server Demo

Frequency of Release Builds  Do not do release builds too often if you rely heavily on RDBMS  Overhead of tracking and validating DB changes Best Practice

Test (NUnit)  Catching compile-time errors promotes developer productivity  Catching run-time errors promotes tester/user productivity  The goal of software should be to solve the users’ business problems, not to make it easier to write more software  To this end, automated testing should buffer the users from integration or deployment errors Demo

Accepting Failure  Gracefully Handling Failures May require the most effort of any part of CI Very specific to project needs What do you do if your build fails? ­Commit? Secondary? Release? How severe was the type of failure ­Invalid notification address ­Still deploy for testing anyway? CI itself is made up of code ­All code has initial bugs ­All code needs to be tested

End Game “[Continuous Integration] helps break down the barriers between customers and development - barriers which I believe are the biggest barriers to successful software development.” -- Martin Fowler

What about the Database?!?  Although it is outside of the scope of this presentation, it is possible to refactor your database  2 Schools of thought Create blank DB from scripts (rare) Version DB with your code & track changes  In general, the practice is more difficult than for code  Database may have more dependencies than you and your project realize

References Martin Fowler’s Article on Continuous Integration Pragmatic Project Automation Open Source Tools Rocks Episodes (Ted Neward) (Eric Sink/Martin Woodward) (Joel Semeniuk) (Kate Gregory) These Slides and All links Posted on my Blog