The document discusses Zend Framework 2 service components. It provides background on service components and their goals of being independently versioned and reusable outside of ZF contexts. It outlines the lifecycle of a service component, from discussion and code review to publication. Finally, it walks through writing a sample service component for Google Cloud Messaging (GCM), including file structure, unit testing, coding standards, documentation, and integration.

1. ZF2: Writing
Service Components
Mike Willbanks | Barnes & Noble
Zend Webinar: Thursday, May 2nd 2013

2. 2
Housekeeping…
• Me
 Sr. Web Architect Manager at NOOK Developer
 Open Source Contributor
 Where you can find me:
• Twitter: mwillbanks G+: Mike Willbanks
• IRC (freenode): mwillbanks Blog: http://blog.digitalstruct.com
• GitHub: https://github.com/mwillbanks

3. 3
Agenda
• Background
• ZF2 Service Components
• Writing a Service Component
• Incorporating your Service Component

4. Background…
Why Service Components

5. 5
A Definition
ZF 1 contained Zend_Service_* components

6. 6
Zend_Service_*
Components were included in the core
distribution

7. 7
Zend_Service_*
Make it easy for people to have it available…

8. 8
1.11.13 Release
Caused several issues

9. 9
Started Getting Messy…

10. Service Component Overview
Goals, Lifecycle, and more.

11. 11
RFC March 2012 “RFC Service Components”
Removal of ZF2 ZendService namespace into a separate namespace
(ZendService) and under their own GitHub project.

12. Goals of ZF2 Service Components
• Ability to version separately from core framework
• Easier to leverage outside of a ZF context
• Encourage service providers to further contribute

13. Services for Contribution (Official Services)
• Independently versioned
• Dependencies on framework versions (2.*, 2.0.*, 2.0.1)
• Maintain dependencies by specific packages
• Must follow ZF coding standards
• Must be unique
 A service that does the same thing should not already exist!

14. 14
Discuss on
Contributor Mailing
List
CR Team Review Fork Repo
Build Component
IRC Vote
(Meeting
Agenda)
Publish!
The Service Component Lifecycle

15. 15
Published ZendService Packages
A published package for ZendService components exist on
packages.zendframework.com.

16. Service Component Maintenance
• Must be maintained for the duration of major versions
 Exceptions must be noted in the ChangeLog
 Component should only state dependency on minor versions
• Maintainers must attempt at all times to keep compatibility
with the latest version
 If unable to maintain, actively recruit, if still unable ZF or CR team
will make a recommendation on the component.

17. Writing a Service Component
By example of ZendServiceGoogleGcm

18. General Information
• Service Components are really just like framework libraries
 However, the namespace implies 3rd party integrations.
 They are also organized like the framework.
• Service Components should be reusable for other
developers
 Write it out based on the API and not just what you need.
• Create reasonable dependencies
 ZendHttp and ZendStdlib being most common.

19. 19
Why Not Modules?

20. Why Not Modules?
• Modules are more specifically for ZF2 Applications
• Service Components are reusable libraries for any code
base.
• Base Rule
 If it involves the MVC; it should more than likely be a module.

21. 21
Starting off…
The file structure of a Service Component.

22. 22
ZendService Components License
https://raw.github.com/zendframework/zf2/master/LICENSE.txt

23. 23
Composer Stub
Main information for your specific library.

24. 24
Composer Stub
Ensure you handle dependencies.

25. Unit Testing
• Quick Start
 Clone an existing Service Component (Currently no skeleton)
 Copy over files from the tests directory: _autoload.php,
Bootstrap.php, phpunit.xml.dist, TestConfiguration.php.dist,
TestConfiguration.php.travis
• You will need to customize
 phpunit.xml.dist – Change out the unit test name.
 TestConfiguration.php.dist – Configure your constants and
configuration.

26. Unit Testing
• Tests should contain proper name spacing
 ZendServiceTestGoogleGcm
• Files you need should be located in an _files directory
inside the test area of your component
 tests/ZendService/Google/Gcm/_files
• Write unit tests like normal!

27. Library Code!
• The guts of the library is what most of us are familiar with
• Write your library inside of your compliant directory
 library/ZendService/Google/Gcm
• Ensure proper namespacing
 ZendServiceGoogleGcm
• Attempt to follow great naming so that it makes sense!

28. Coding Standards
• Remember to make use of the coding standards!
 Docblocks
 Import the proper packages from their respective namespaces
 Read the coding standards doc:
• http://framework.zend.com/wiki/display/ZFDEV2/Coding+Standards
• Mainly; PSR-0, PSR-1, PSR-2 (there are slight differences)

29. Best Practices
• Follow conventions
 PSR-0/1/2, file locations, options classes
• Hard dependencies
 Use the constructor!
 Only set dependencies for items you require!
• Write Tests
 Hook into Travis-CI, go for 100% code coverage
• Discoverability
 Put the component on Packagist, submit it for inclusion to
ZendService.

30. Documentation
• The most dreaded part of the job…
• All of the documentation is in the “zf2-documentation”
project under the “zendframework” github organization.
 This will likely change for services in the future.
• Fork the project
• Create a feature branch: feature/service-google-gcm
• Write your documentation
• Submit a PR

31. 31
Documentation is built out of reStructuredText
Yes, Docbook has gone away; so fear not!

32. 32
Language Files
Always start with English first aka “en” as it is the default in the event
a translation is missing.

33. 33
Modify docs/language/en/index.rst to add in your new service
Having a table of contents is a good thing!

34. 34
Modify docs/language/en/index.rst to add in your new service
Follow the convention!

35. 35
Write Away!
docs/language/en/modules/zendservice.google.gcm.rst or the like

36. 36
Seeing your Documentation
• Install the proper tools
 apt-get install python-setuptools python-pygments
 easy_install -U Sphinx
• Enter the docs/ directory
• Run: make html

37. 37
Your documentation will now be in:
docs/_build/html
Review for errors before sending the PR

38. Integrating your Service
Add the module to the composer configuration
Add in potential configuration
Setup the service manager
Fetch it inside of a controller

39. 39
Add to your composer.json!
Followed by “php composer.phar install”

40. 40
Handling Configuration
Likely in /path/to/zf2app/config/autoload/local.php

41. 41
Service Manager Setup
Creating a simple factory to get a configured Client.

42. 42
Leveraging your Service Factory in a Controller
We can easily fetch it now when we have a ServiceLocator.

43. Questions?
These slides will be posted to SlideShare & SpeakerDeck.
 SpeakerDeck: http://speakerdeck.com/u/mwillbanks
 Slideshare: http://www.slideshare.net/mwillbanks
 Twitter: mwillbanks
 G+: Mike Willbanks
 IRC (freenode): mwillbanks
 Blog: http://blog.digitalstruct.com
 GitHub: https://github.com/mwillbanks