1. PHP Deployment with
Subversion
Lorna Mitchell
Ibuildings
The PHP Professionals
Ibuildings

2. About Me
• Lorna Mitchell
• PHP Developer/Consultant/Trainer with Ibuildings
• ZCE
• Member of http://www.phpwomen.org
• Personal blog at http://www.lornajane.net
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3. SVN and Deployment
• Deployment process
• Deployment mechanism
• Subversion
• Other tools
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4. In The Beginning
• One Developer
• Code on PC
• FTP / SCP / Upload to live server
• It works!
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5. Early Development Team
• More developers
• Development server
• Ideally one copy per developer, a testing/staging
server and a live platform
Dev
LIVE area
Dev
Dev
area
area
Staging
Dev Dev
area area
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6. Deployment Considerations
• Multiple platforms prompt context-aware
configuration
• File permissions may need checking, for example
on cache directories
• If the live site has uploaded files stored in the file
system, need to preserve this content
• Compile step for initialising compiled templates or
populating caches
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7. Deployment Plan
• A deployment plan is a recipe for moving code
• Step-by-step instructions for setting up a new
version of code
• Must always be accompanied by a rollback plan
• This process should be as automated as possible
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8. Example Deployment Plan
• Avoid missing steps when putting live
Export from repository
Tar
Upload
Untar
Set permissions
Switch symlinks
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9. Symlinks
Live-site (symlink)
Existing live code New code version
existing ready
preparing
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10. Code Transport
• Copy development code to live
• Rsync development code to live
• Check out to live and update
• Export to live
• Patch changes from last live version only – requires
version meta-data
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11. Commit Hooks
• Subversion can run scripts on given events, called
“commit hooks”
 Pre-commit
 Post-commit
• Run test suite
• Coding standards conformance
• Syntax check
• No “forgetting” any steps
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12. Notifications
• Can use the commit hooks to trigger information
• Email team
 Diff
 Changes
 Test coverage/outcomes
• Ticker/big screen
• Nabaztag
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13. Source Control Packages
• Subversion http://subversion.tigris.org
• CVS http://www.cvshome.org
• GIT http://git.or.cz
• Bazaar http://bazaar-vcs.org
• Visual Source Safe
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14. Source Control Clients
• Command line tools
• TortoiseSVN: http://tortoise.tigris.org
• IDE Plugins: for Zend Studio, Komodo, etc
• WebSVN: http://websvn.tigris.org
 SFM (Safe For Managers)
• Trac: http://trac.edgewall.org/
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15. Source Control Concepts
• Individuals communicate with repository
• Keeping place
• Collaboration tool
• Historic versions
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16. Collaboration
• Two people operate on different files
 Changes are combined
• Two people change the same file
 Changes are merged if changes don't overlap
• Allows teams to easily work on different parts of
the system
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17. Collaboration Example
$greeting = 'hello world';
echo $greeting;
$greeting = 'hey people'; $greeting = 'hello world';
echo $greeting; print $greeting;
$greeting = 'hey people';
print $greeting;
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18. Conflicts
• Two people edit the same part of the same file
 Includes both adding a new method to the end of a class
• Subversion will notify you of the conflict and
provide:
 Your most recent version
 The version from the repository
 Its best guess at a merge with some notation for where
the overlaps are
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19. Conflict Example
$greeting = 'hello world';
echo $greeting;
$greeting = 'hey people'; $greeting = 'hi universe';
echo $greeting; echo $greeting;
$greeting = 'hey people';
echo $greeting;
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20. Conflict Example
greeting.php greeting.php.r365
<<<<<<< .mine $greeting = 'hello world';
$greeting = 'hi universe'; echo $greeting;
=======
$greeting = 'hey people';
>>>>>>> .r366
echo $greeting;
greeting.php.mine greeting.php.r366
$greeting = 'hi universe'; $greeting = 'hey people';
echo $greeting; echo $greeting;
• Correct greeting.php and then let Subversion know
you have resolved the conflict
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21. Branching
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22. Branching Example
trunk
version 1.1
Development done,
merge in changes
version 1.2
development branch
bug fix
Delete extra
branch
bug fix
backport
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23. Tagging Versions
• Source control tools allow you to label releases,
called “tags”
• Subversion has one revision number for a whole
repository, incrementing on every commit
• CVS has one revision number per file
• In either case its nice to have “client preview” or
“release 4.11” as human readable markers
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24. Repository Structure
• Repository layout choices
• Deployment point choices
• Affected by process
• Dependent on product type
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25. Cyclic Releases
• Periodic release cycle
• Need to maintain existing version
• Start developing new version
• May need to fix bugs in both versions
• Use branching
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26. Continuous Releases
• Changes to branch
• Branch merged to trunk
• Can patch changes from branch to trunk for bug
fixes
• Deployment from trunk
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27. Branch Deployment
trunk
version 1.1
development branch
version 1.2
testing
deployment!
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28. Live Branch
• Changes to branch
• Branch merged to trunk
• Testing performed on trunk
• Changes then patched to live branch
• Deployment from live branch
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29. Live Branch Deployment
trunk live branch
development branch
testing
deployment!
approved
changes
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30. Database Versioning
• Copying exported versions around
 Risk losing live data
• Make structure changes to all platforms
 Put objects in scripts
• Simple patching strategy
 No direct database operations
 Numbered patch files in subversion
 Include patches in script
 Give database awareness of current patch level
 Keep an installation script updated with all changes
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31. Database Rollback
• Write patch file
• Also write undo file
-- release.2.0.sql
create table friends(
user_id int not null
friend_user_id int not null
created_date timestamp default current_timestamp not null
);
-- release.2.0.undo.sql
drop table friends;
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32. DbMorph
• Tool developed by Maggie Nelson
• DbMorph, very early version http://sourceforge.net/
projects/dbmorph
• Also see Maggie's homepage
http://objectivelyoriented.com
• Slides from her talk at php|tek “Keeping Your
Database and PHP in Sync”
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33. Other Tools
• Phing http://phing.info
 Project build system based on Apache Ant
 XML configuration
 Integration with SVN
 Available through PEAR
• Phar http://pecl.php.net/package/phar
 Package management for PHP
 Like JAR for Java
 Self-extracting option
 PECL module
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34. SVN and Deployment
• Deployment process
• Deployment mechanism
• Subversion
• Other tools
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35. Questions?
Lorna Mitchell - lorna@ibuildings.com
Ibuildings