WordPress Concepts

General

• Tom McFarlin.
  • Beginner Tips for Getting Started with WordPress Development. Tuts+, 2014.
    • (1) Start Small, (2) Study Existing Code, (3) Understand the Coding Standards, (4) Participate in Meetups and WordCamps, (5) Read Blogs.
  • A Simple Guide for Organizing WordPress-centric Classes. 2018.
    • Suggests that we place WordPress centric code within a WordPress directory to separate it from problem domain code.
  • Writing Better Code for WordPress-Based Projects. 2017.
    • Adapts Joel’s Test for software development projects to WP specifically.
  • We Need Better Abstraction in WordPress Projects. 2013.
    • Provides an example of code pre-abstraction and post-abstraction.
  • Multiple Objects Writing Data: How to Avoid This. 2017.
    • Recommends using a single object to handle writing to / reading from the data store to avoid side effects from multiple objects/functions attempting to perform simultaneous reads or writes.
• Rachel McCollins. DRY WordPress Theme Development. Tuts+, 2015.
• Damien Logghe. Tips for Best Practices in WordPress Development. Tuts+, 2014.
  • Covers use of WP coding standards, avoiding function name collisions, commenting code, and security basics such as data sanitization and nonces.
• John Hughes. How to Become a WordPress Developer: Tips to Get You Started. themeisle, 2018.

Best Practices

• WordPress Best Practices for Developers. wpengine, 2019.
• WordPress Plugin Development – Best Practices. wooninjas, 2017.
• Tom McFarlin.
  • WordPress and The Single Responsibility Principle. 2014.
  • The Single Responsibility Principle in WordPress. 2016.
  • Single Responsibility Principle: WordPress Menus. 2016.
  • The Single Responsibility Principle in WordPress. 2016.

Object Oriented Programming (OOP)

• Josh Pollock. Advanced OOP for WordPress Series. Torque, 2018.
  • Part 1: Customizing REST API Endpoints To Improve WordPress Search
  • Part 2: Setting Up Automated Testing Of WordPress REST API Plugins
  • Part 3: Unit Testing For WordPress REST API Plugins
  • Part 4: Setting Up With WordPress Test Suite For Integration Testing
  • Part 5: Using The WordPress Test Suite For Integration Testing
  • Part 6: Continuous Integration For WordPress Plugins
  • Part 7: Refactoring Is An Opportunity To Adopt Test-Driven Development
  • Part 8: Developing New Features For Extensible WordPress Plugins Using Test-Driven Development
  • Part 9: Extensible Plugins Using the Plugins API
  • Customizing REST API Endpoints To Improve WordPress Search
• Daniel Pataki.
  • An Introduction to Object-Oriented Code for WordPress Plugins. wpmudev, 2016.
  • Advanced WordPress Development: Writing Object-Oriented Plugins. wpmudev, 2016.
  • Creating WordPress Plugins in an Object Oriented Way. wpmudev, 2015.
• David Hayes.
  • Introduction to Object-Oriented PHP for WordPress Developers, wpshout, 2018.
    • Great introduction. Covers classes, objects, properties, methods, procedural programming, instances, instantiation, arrows, $this, private/public.
  • Is WordPress Object-Oriented? A Thorough Exploration. wpshout, 2019.
• Tom McFarlin.
  • Object-Oriented Programming in WordPress. envatotuts+, 2014.
    • 1. An Introduction.
    • 2. Classes.
    • 3. Types.
    • 4. Control Structures I.
    • 5. Control Structures II.
    • 6. Functions and Attributes.
    • 7. Scope.
    • 8. Building the Plugin I.
    • 9. Building the Plugin II.
    • 10. Document the Plugin I.
    • 11. Document the Plugin II.
    • 12. Inheritance I.
    • 13. Inheritance II.
    • 14. A Summary.
  • Object-Oriented Programming in WordPress. 2017.
    • Part 1: Analysis (Part 1).
    • Part 2: Analysis (Part 2).
    • Statement of Work.
    • Understanding Customer Expectations.
    • Terms and Conditions.
  • Object-Oriented WordPress Plugin Development. 2013.
  • Properly Writing WordPress Plugin Constructors. 2016.
• Carl Alexander.
  • How to Approach Object-Oriented Programming with WordPress. 2019.
  • Discovering Object-Oriented Programming using WordPress book ($$)
  • Why Object-Oriented Programming Is Your Next step as a WordPress Developer.
  • Organizing Your Files in an Object-Oriented WordPress Plugin.
  • Using Inheritance with WordPress.
• Tom McFarlin. WordPress Widgets: An Object Oriented Approach. 2017-2018.
  • An Object-Oriented Approach.
  • How to Detect Object-Oriented Programming.
  • Starting with Standards.
  • Refactoring (Part 1).
  • Refactoring (Part 3).
  • Two Pillars of Object-Oriented Programming (Part 1).
  • Two Pillers of Object-Oriented Programming (Part 2).
  • Understanding Interfaces.
  • Abstract Classes
    • Part 1: Abstracting Behavior.
    • Part 2: Abstract Classes and Interfaces.
  • Looking at Polymorphism In-Depth.
• Tom McFarlin. WordPress Widgets Refactoring. 2019.
  • Part 13.
• Simon Codrington. Object Orientated Development with WordPress. sitepoint, 2015.
• Josh Pollock. Demystifying Object-Oriented PHP for WordPress Developers. torque, 2014.

Namespaces and Autoloading

You may also want to look at our separate pages on Package Management and Autoloading as well as on Composer.

• Justin Tadlock.
  • Beyond Prefixing: A WordPress Developer’s Guide to PHP Namespaces. wptavern, 2019.
  • PHP Namespaces for WordPress Developers. 2018.
• Steve Grunwell. A Crash-course in PHP Namespaces for WordPress Developers. 2018.
• Josh Pollock.
  • Why and How to Use Class Autoloading and Namespacing to Improve WordPress Development. Torque, 2015.
  • Using Namespaces in WordPress Development. Torque, 2015.
  • Using a Class Autoloader to Improve WordPress Development. Torque, 2015.
• Tom McFarlin.
  • Namespaces and Autoloading in WordPress. 2017.
    • Lengthy article that introduces using namespaces and autoloading with WP, the autoloading is vanilla, not Composer, etc.
  • Object-Oriented Autoloading in WordPress (Parts 1-3). tutsplus, 2016.
  • Using a PHP Autoloader in WordPress. 2016.
  • How to Use PSR-4 Autoloading WordPress Plugins. 2017.
• David Hayes. What “Namespaces” Mean for WordPress Developers. wpshout, 2015.
• Alain Schlesser. Adding a Central Autoloader to WordPress. 2016.
• Nico Amarilla. How to Use Autoloading and a Plugin Container in WordPress Plugins. smashing magazine, 2015.
• Ben Martinez-Bateman. Namespacing and Autloading. roots, 2019.

Coding Standards

• Tom McFarlin.
  • Coding Standards and Guidelines (“When in Rome, Program Like the Romans”). 2014.
    • While Tom’s stance may have changed some (see above articles) since writing this piece it is still a helpful stance on holding our particular methods loosely and adapting to different developer cultures.
  • Basic Coding Standards via PSR-1. 2017.
    • A sequel of sorts to Using the PSRs, Tom covers some of the ways in which using the PSRs can be difficult for WP developer’s legacy code.
  • Using the PSRs (Versus the WordPress Coding Standards). 2017.
    • Tom, who for a long time recommended using WP standards over PSR’s explains why he has now prioritized PSR over WP standards.
  • Two Ways to Develop WordPress Plugins: Object-Oriented Programming. tutsplus, 2012.
• Josh Pollock.
  • How to Enforce Code Standards in WordPress Development Using Composer. torque, 2018.
  • Don’t Follow WordPress Coding Standards. Torque, 2018.
    • A good read on why one may not always want to follow WordPress’ coding standards over PHP standards.
• John Hughes. The Newbie Developer’s Guide to WordPress’ PHP Coding Standards. torque, 2017.

Design Patterns

• See our separate page on Design Patterns.