PHP Mastery Object-Oriented Design & Test-Driven Development

This section introduces building a bug report submission app in PHP, using composer and PHPUnit, and emphasizes test-driven development and object-oriented design to create reliable, well-tested code.

Create the core project folders by establishing the source directory and a test territory, then organize config, contracts, database with drivers, exceptions, helpers, logger, and templates for emails and scripts.

Convert PHP warnings and notices into exceptions by mapping severity, message, file, and line to a custom exception, then integrate it with the error handling class.

Define a PSR-3 logger interface with emergency, alert, critical, error, warning, notice, info, and debug levels, plus a log method and a log level class.

Test and implement a logging system by validating log levels, messages, and key-value data, then confirm file-based application logs for emergency and info events.

Create a PHPUnit configuration file in the project root to define bootstrap and encoding, and configure unit and functional test suites with color, error-to-exception conversion, and stop-on-failure.

Extend unit tests by adding an application test that validates basic data from the application instance, including environment, time, and log path, using assertions.

Explore unit testing of a logger class, validating interface implementation, writing and verifying log files at multiple levels, and handling invalid log levels in a test-driven approach.

Build a database abstraction layer for runtime switching between PDU and Mya's Kukali API, using a connection interface and dependency injection to stay loosely coupled, with unit tests.

Develop and test a MySQLi database connection for a school using an object-oriented design, implementing an abstract connection, a school-specific connector, and credential handling within a test-driven workflow.

Build an abstract database query builder in PHP using dependency injection and a database connection interface, supporting PDO and MySQLi, prepared statements, placeholders, and bindings.

Define and implement abstract methods in the query builder, including get, count, prepare, execute, and mapping to objects, then add create, update, delete, find by, and first for data retrieval.

Extend the query builder to implement abstract methods for the PDO API, wiring prepare, execute, fetch, and count, enabling fetch into classes and last insert handling.

Explore implementing abstract methods for the MySQLi API in PHP, using reflection to bind parameters, manage result sets, and execute prepared statements with type-safe bindings (string, integer, double).

Demonstrates how to automatically clean up the database for each test by wrapping in a transaction and rolling back, using a query factory and test credentials.

Explore adding more test cases in a PHP object-oriented and test-driven workflow, covering find by id and by value, updates, and deletes, while debugging query behavior.

Describe logging during the request life cycle and exception handling in a bug-report workflow, using try-catch blocks, log messages, and context data like post content and errors.