ZacharyZhang-NY
e74dafcd36
Three independently ugly bugs that all fed the same log flood:
* Electron's `WebFrameMain.send` writes every "Render frame was disposed"
to stderr via `console.error`. When the worker fans a second
agent-event past a reloading renderer, we produced thousands of
identical lines and stalled the main loop on stderr I/O. Added a
`mainFrame.detached` guard so the send is short-circuited before
Electron's own catch block fires, and installed a targeted filter in
`suppress-warnings.ts` (now actually imported from the entry point)
so the specific `console.error("Error sending from webFrameMain:"…)`
noise never reaches the terminal. Any other payload still surfaces.
* `dispatchAgentMessage` accepted the human-reader sentinel as a wake
target when an agent replied to `__board__` — `wakeAgentIfPossible`
then called `db.getAgent("__board__")`, threw, and the dispatcher
kept repeating on every send. Strip `HUMAN_SENDER_ID` at
`resolveMessageWakeTargets`, and keep a defense-in-depth guard in the
heartbeat so a stray caller (future automation fan-out) cannot
reintroduce the crash.
* Pi's skills loader rejects any SKILL.md whose frontmatter `name`
diverges from its parent directory. The four bundled `my-writing-style`
copies declared `name: writing-style-skill`, so every install emitted
a warning and dropped the skill. They also lived as orphan gitlinks
(mode 160000 without .gitmodules), and the global `*.md` gitignore
hid every other SKILL.md from version control. Fixed the frontmatter
to match the dir, converted the dangling submodules to plain trees,
and allowlisted `builtin-skills/**/*.md` so a fresh clone carries the
catalogue instead of silently losing it.
97 lines
3.0 KiB
Markdown
97 lines
3.0 KiB
Markdown
---
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title: Each Use Case Has One Reason to Change
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impact: HIGH
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impactDescription: isolates change impact, enables parallel development
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tags: usecase, single-responsibility, cohesion, srp
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---
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## Each Use Case Has One Reason to Change
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Each use case class should orchestrate exactly one application-specific workflow. Combining multiple use cases creates coupling that forces unrelated changes together.
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**Incorrect (multiple use cases in one class):**
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```python
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class OrderService:
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def __init__(self, repo, payment, shipping, notification):
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self.repo = repo
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self.payment = payment
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self.shipping = shipping
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self.notification = notification
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def create_order(self, items, customer_id):
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# Use case 1: Create order
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order = Order.create(items, customer_id)
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self.repo.save(order)
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return order
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def process_payment(self, order_id, payment_method):
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# Use case 2: Process payment
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order = self.repo.find(order_id)
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self.payment.charge(order.total, payment_method)
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order.mark_paid()
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self.repo.save(order)
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def ship_order(self, order_id, address):
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# Use case 3: Ship order
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order = self.repo.find(order_id)
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tracking = self.shipping.create_shipment(order, address)
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order.mark_shipped(tracking)
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self.notification.send_shipped(order)
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self.repo.save(order)
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# Changes to shipping logic force retest of payment logic
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```
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**Correct (separate use case classes):**
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```python
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class CreateOrderUseCase:
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def __init__(self, repo: OrderRepository):
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self.repo = repo
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def execute(self, command: CreateOrderCommand) -> OrderId:
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order = Order.create(command.items, command.customer_id)
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self.repo.save(order)
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return order.id
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class ProcessPaymentUseCase:
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def __init__(self, repo: OrderRepository, payment: PaymentGateway):
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self.repo = repo
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self.payment = payment
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def execute(self, command: ProcessPaymentCommand) -> None:
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order = self.repo.find(command.order_id)
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self.payment.charge(order.total, command.payment_method)
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order.mark_paid()
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self.repo.save(order)
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class ShipOrderUseCase:
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def __init__(
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self,
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repo: OrderRepository,
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shipping: ShippingService,
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notification: NotificationPort
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):
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self.repo = repo
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self.shipping = shipping
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self.notification = notification
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def execute(self, command: ShipOrderCommand) -> TrackingNumber:
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order = self.repo.find(command.order_id)
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tracking = self.shipping.create_shipment(order, command.address)
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order.mark_shipped(tracking)
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self.notification.send_shipped(order)
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self.repo.save(order)
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return tracking
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```
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**Benefits:**
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- Changes to shipping don't affect payment tests
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- Teams can work on different use cases in parallel
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- Each use case has minimal dependencies
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Reference: [Clean Architecture - Use Cases](https://blog.cleancoder.com/uncle-bob/2012/08/13/the-clean-architecture.html)
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