interfaces-and-autowiring · diff
git:20261005.042befb to git:20261005.2187271
18 added, 12 removed. Audit A to A.
---
name: interfaces-and-autowiring
description: "Master Symfony Dependency Injection with autowiring, #[Target] interface binding, decoration, and tagged services"
capabilities: [read, search]
tags: [architecture]
# projected by `bun run build` — do not edit by hand
allowed-tools:
- Read
- Glob
- Grep
---
# Interfaces And Autowiring (Symfony)
## Use when
- - Refining architecture/workflows/context handling in Symfony projects.
- - Planning and executing medium/complex changes safely.
+ - A service depends on a concrete class and must be swappable or replaced in tests.
+ - Several implementations of one interface exist and the right one must be injected.
+ - Adding cross-cutting behavior (logging, caching, retries) around an existing service.
+ - Injecting scalars, parameters, env vars, or every service carrying a tag.
+ - Autowiring fails with "cannot autowire" or an ambiguous type.
## Default workflow
- 1. Establish current boundaries, constraints, and coupling points.
- 2. Propose smallest coherent architectural adjustment.
- 3. Execute in checkpoints with validation at each stage.
- 4. Summarize tradeoffs and follow-up backlog.
+ 1. Extract a focused interface for what the consumer actually needs.
+ 2. Let autowiring bind it when there is a single implementation.
+ 3. With several implementations, pick one per consumer through a named alias and `#[Target]`.
+ 4. Add behavior around a service with `#[AsDecorator]` instead of editing or extending it.
+ 5. Inject scalars with `#[Autowire]` and tagged collections with `#[AutowireIterator]`.
+ 6. Confirm the result with `debug:autowiring` for each type involved.
## Guardrails
- - Use existing project patterns by default.
- - Avoid broad refactors without explicit need.
- - Keep decision log clear and auditable.
+ - Constructor injection with `private readonly` dependencies; no setter injection, no container access.
+ - Keep interfaces small: one consumer need per interface.
+ - Make services `final` by default and decorate them rather than extend them.
+ - Use lazy services or service closures only for expensive dependencies that some paths skip.
## Progressive disclosure
- Use this file for execution posture and risk controls.
- Open references when deep implementation details are needed.
## Output contract
- - Architecture/workflow changes.
- - Checkpoint validation outcomes.
- - Residual risks and next steps.
+ - Interfaces and the bindings or aliases that select each implementation.
+ - Decorators or tagged collections, with their priority.
+ - The `debug:autowiring` output for the types involved.
## References
- `reference.md`