ignitae Academy

Hexagonal Architecture in PHP

Ports, adapters, command handlers, domain events and aggregate invariants: a task-tracking slice built the way a framework-free core should be.

Syllabus

Ports and adapters

The domain owns the interface; infrastructure implements it
Ports and adapters: repository, id generator, clock (exercise)

Command handlers

A command is a request; a handler is the one place it is fulfilled
Command handlers over ports (exercise)

Domain events

Domain events: record what happened, publish after you persist
Domain events: record, save, then publish (exercise)

Aggregates and invariants

An aggregate is the boundary inside which rules are always true
Project aggregate: invariants at the boundary (exercise)

Testing through the ports

Fakes, stubs and spies: fast tests that never touch a framework
RemindOverdueTasks, tested through fakes, stubs and spies (exercise)