Implementation Plan: Checklist Data Layer

Branch: 001-checklist-data-layer | Date: 2026-03-22 | Spec: /specs/001-checklist-data-layer/spec.mdInput: Feature specification from /specs/001-checklist-data-layer/spec.md

Summary

Implement the core database models for the camply smart poller: User, UniqueTarget, UserScan, and ScanResult. This layer enables de-duplicated polling by tracking unique campground/date combinations and associating them with individual user preferences.

Technical Context

Language/Version: Python 3.12 Primary Dependencies: SQLAlchemy 2.0 (Mapped/mapped_column), Alembic, Pydantic v2 Storage: PostgreSQL (with JSONB support for filters) Testing: pytest (unit tests for models and constraints) Target Platform: Dockerized Backend Project Type: Web Service (Backend Data Layer) Performance Goals: Sub-millisecond lookup for unique targets via indexed hashes. Constraints: Composite primary keys for provider-sourced entities; SHA256 hashing for de-duplication. Scale/Scope: Initial data layer to support Phase 1 MVP.

Constitution Check

GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.

1. Reliability & Precision: Does the unique hashing ensure no duplicate API calls? (Yes, via SHA256 constraints).
2. Type Safety: Are all models using SQLAlchemy 2.0 Mapped types? (Yes).
3. Automated Verification: Is there a plan for unit tests and migrations? (Yes).
4. Separation of Concerns: Is this strictly in backend/packages/db? (Yes).

Project Structure

Documentation (this feature)

specs/001-checklist-data-layer/
├── spec.md              # Feature specification
├── plan.md              # This file
├── research.md          # Phase 0 output
├── data-model.md        # Phase 1 output
├── quickstart.md        # Phase 1 output
└── checklists/
    └── requirements.md  # Quality checklist

Source Code (repository root)

backend/
└── packages/
    └── db/
        └── db/
            └── models/
                ├── users.py
                ├── unique_targets.py
                ├── user_scans.py
                └── scan_results.py

Structure Decision: Models will be added to the existing backend/packages/db package, following the established pattern of one file per major entity.

Complexity Tracking

Violation	Why Needed	Simpler Alternative Rejected Because
None	N/A	N/A