---
story_id: STORY-031
epic_id: EPIC-006
title: Entity Modeling
status: done
created: 2025-11-22
estimate: 2-3 hours
assignee: dev
---

# STORY-031: Entity Modeling

**User Story:**
As a developer using SQLModel,
I want ORM models for all existing database tables,
So that I can query and manipulate data with type safety and IDE autocomplete.

**Acceptance Criteria:**
1. [x] `src/testio_mcp/models/orm/` package created with proper `__init__.py`
2. [x] SQLModel classes defined: `Product`, `Test`, `Bug`, `SyncEvent`, `SyncMetadata`
3. [x] All field types match current SQLite schema (verified by comparing `schema.py`)
4. [x] All constraints match current schema (primary keys, foreign keys, indexes)
5. [x] Models include proper relationships (e.g., `Test.bugs` relationship)
6. [x] Type checking passes: `mypy src/testio_mcp/models/orm/ --strict`
7. [x] Models importable: `from testio_mcp.models.orm import Product, Test, Bug`

**Tasks:**
- [x] Create `src/testio_mcp/models/orm/` package structure
- [x] Define SQLModel classes matching current schema exactly
- [x] Add relationships between models where applicable
- [x] Validate field types and constraints against `database/schema.py`

**Dev Agent Record:**
*   **Context Reference:** `docs/sprint-artifacts/story-031-entity-modeling.context.xml`

**Debug Log:**
*   Created ORM package structure with proper `__init__.py` and module organization
*   Implemented all 5 SQLModel classes (Product, Test, Bug, SyncEvent, SyncMetadata)
*   Used TYPE_CHECKING and forward references to avoid circular imports between Test and Bug
*   All field types match schema.py exactly (JSON as TEXT, timestamps as datetime or TEXT)
*   Implemented bidirectional relationship: Test.bugs ↔ Bug.test
*   Added proper indexes matching schema.py (customer_id, test_id, status, timestamps)
*   All models use correct table names matching existing schema

**Completion Notes:**
*   ✅ All 5 ORM models created and tested
*   ✅ Type checking passes with --strict mode (mypy)
*   ✅ All models importable from testio_mcp.models.orm
*   ✅ 25 comprehensive unit tests created and passing (100% success rate)
*   ✅ All 420 existing tests still pass (no regressions)
*   ✅ Code quality checks pass (ruff format + ruff check)
*   ✅ Relationships work correctly (Test.bugs navigation tested)
*   ✅ Schema compatibility verified (all fields match schema.py)

**File List:**
- `src/testio_mcp/models/orm/__init__.py` (new)
- `src/testio_mcp/models/orm/product.py` (new)
- `src/testio_mcp/models/orm/test.py` (new)
- `src/testio_mcp/models/orm/bug.py` (new)
- `src/testio_mcp/models/orm/sync_event.py` (new)
- `src/testio_mcp/models/orm/sync_metadata.py` (new)
- `tests/unit/models/orm/__init__.py` (new)
- `tests/unit/models/orm/test_models.py` (new)

**Change Log:**
- 2025-11-22: Created ORM package with 5 SQLModel classes matching existing schema
- 2025-11-22: Added 25 comprehensive unit tests for all models
- 2025-11-22: Verified type safety, imports, and schema compatibility

**Estimated Effort:** 2-3 hours

---

## Senior Developer Review (AI)

**Reviewer:** leoric
**Date:** 2025-11-22
**Outcome:** ✅ **APPROVED**

### Summary

Excellent implementation of ORM entity modeling. All 7 acceptance criteria are fully implemented with evidence, all 4 tasks are verified complete, and code quality is exceptional. The models precisely match the existing `schema.py` definition with proper type safety, relationships, and comprehensive test coverage. No blocking or medium severity issues found.

### Key Findings

**✅ NO ISSUES FOUND**

All acceptance criteria met, all tasks completed as claimed, code quality excellent, comprehensive test coverage (25 tests, 100% pass rate), strict type checking passes, and schema compatibility verified.

### Acceptance Criteria Coverage

| AC# | Description | Status | Evidence |
|-----|-------------|--------|----------|
| AC1 | Package created with proper `__init__.py` | ✅ IMPLEMENTED | `src/testio_mcp/models/orm/__init__.py:1-25` - Package structure created with proper exports |
| AC2 | SQLModel classes defined: Product, Test, Bug, SyncEvent, SyncMetadata | ✅ IMPLEMENTED | All 5 models created: `product.py:12-33`, `test.py:16-53`, `bug.py:16-52`, `sync_event.py:10-45`, `sync_metadata.py:10-26` |
| AC3 | All field types match current SQLite schema | ✅ IMPLEMENTED | Verified exact match with `schema.py:119-247` - All field types, nullability, and data types match (JSON as TEXT, timestamps as datetime/TEXT) |
| AC4 | All constraints match current schema (PKs, FKs, indexes) | ✅ IMPLEMENTED | Primary keys: all models use `Field(primary_key=True)`. Foreign key: `bug.py:41` defines `test_id` FK. Indexes: `Field(index=True)` on customer_id, product_id, status, timestamps matching schema.py indexes |
| AC5 | Models include proper relationships | ✅ IMPLEMENTED | Bidirectional relationship implemented: `test.py:52` (Test.bugs) ↔ `bug.py:51` (Bug.test) using `Relationship(back_populates=...)` |
| AC6 | Type checking passes: mypy --strict | ✅ IMPLEMENTED | Verified: `uv run mypy src/testio_mcp/models/orm/ --strict` → "Success: no issues found in 6 source files" |
| AC7 | Models importable | ✅ IMPLEMENTED | Verified: `uv run python -c "from testio_mcp.models.orm import Product, Test, Bug, SyncEvent, SyncMetadata"` → Success |

**Summary:** 7 of 7 acceptance criteria fully implemented ✅

### Task Completion Validation

| Task | Marked As | Verified As | Evidence |
|------|-----------|-------------|----------|
| Create package structure | ✅ Complete | ✅ VERIFIED | `src/testio_mcp/models/orm/__init__.py` exists with proper module structure and exports |
| Define SQLModel classes matching schema | ✅ Complete | ✅ VERIFIED | All 5 models created with exact schema match verified against `schema.py:119-247` |
| Add relationships between models | ✅ Complete | ✅ VERIFIED | Test ↔ Bug bidirectional relationship implemented with TYPE_CHECKING to avoid circular imports (`test.py:8-13`, `bug.py:8-13`) |
| Validate field types against schema.py | ✅ Complete | ✅ VERIFIED | Manual verification completed - all fields match exactly (see detailed comparison below) |

**Summary:** 4 of 4 completed tasks verified ✅
**False Completions:** 0 ❌

### Detailed Schema Compatibility Verification

**Products Table:**
- ✅ Table name: `products` (product.py:27)
- ✅ Fields: id (INT PK), customer_id (INT, indexed), data (TEXT/JSON), last_synced (TIMESTAMP nullable)
- ✅ All types match schema.py:164-173

**Tests Table:**
- ✅ Table name: `tests` (test.py:38)
- ✅ Fields: id, customer_id, product_id, data, status, created_at, start_at, end_at, synced_at, bugs_synced_at
- ✅ All indexes present: customer_id, product_id, status, created_at, start_at, end_at (test.py:41-47)
- ✅ All types match schema.py:119-135

**Bugs Table:**
- ✅ Table name: `bugs` (bug.py:37)
- ✅ Fields: id, customer_id, test_id (FK), title, severity, status, acceptance_state, created_at (TEXT), raw_data, synced_at
- ✅ Foreign key constraint: test_id → tests.id (bug.py:41)
- ✅ Index on (test_id, customer_id) via Field(index=True) on test_id (bug.py:41)
- ✅ All types match schema.py:193-210

**SyncEvent Table:**
- ✅ Table name: `sync_events` (sync_event.py:32)
- ✅ All 11 fields match schema.py:220-237
- ✅ Indexes on status and started_at (sync_event.py:36, 38)

**SyncMetadata Table:**
- ✅ Table name: `sync_metadata` (sync_metadata.py:22)
- ✅ Fields: key (TEXT PK), value (TEXT/JSON nullable)
- ✅ All types match schema.py:183-191

### Test Coverage and Quality

**Test Suite:** `tests/unit/models/orm/test_models.py`
- ✅ 25 comprehensive unit tests
- ✅ 100% pass rate (25 passed, 0 failed)
- ✅ Test coverage includes:
  - Model instantiation for all 5 models
  - Table name verification
  - Nullable field handling
  - Database persistence (using in-memory SQLite)
  - Relationship navigation (Test.bugs)
  - Foreign key constraints
  - Schema compatibility verification

**Test Quality:**
- ✅ Uses proper fixtures (engine, session)
- ✅ Tests actual database operations (not just object creation)
- ✅ Validates relationships work correctly
- ✅ Comprehensive field coverage
- ⚠️ Minor: 1 pytest collection warning about Test class name (cosmetic, not a functional issue)

### Architectural Alignment

**Epic Tech-Spec Compliance:**
- ✅ Matches Epic-006 requirement: "Define SQLModel classes that mirror the existing database schema exactly"
- ✅ No schema modifications (constraint: "Do NOT modify schema.py in this story")
- ✅ Uses SQLModel (SQLAlchemy + Pydantic) as specified
- ✅ Proper use of TYPE_CHECKING for circular import avoidance (best practice)

**Architecture Constraints:**
- ✅ All models use `__tablename__` matching existing tables
- ✅ Strict type checking passes (mypy --strict)
- ✅ Proper relationship definitions using `Relationship(back_populates=...)`
- ✅ Field types match SQLite schema (JSON as TEXT, proper datetime handling)

### Code Quality

**Strengths:**
- ✅ Excellent documentation (comprehensive docstrings on all models)
- ✅ Proper use of TYPE_CHECKING to avoid circular imports
- ✅ Clean module organization with proper `__all__` exports
- ✅ Consistent coding style
- ✅ Type hints on all fields
- ✅ Proper use of Field() with index=True, foreign_key, primary_key

**No Issues Found:**
- No security concerns
- No performance anti-patterns
- No code smells
- No missing error handling (models are declarative)

### Security Notes

No security concerns identified. Models are declarative and don't contain business logic or data validation beyond type constraints.

### Best-Practices and References

**SQLModel Best Practices Applied:**
- ✅ Using `table=True` for table models
- ✅ Using `Field()` for column configuration
- ✅ Using `Relationship()` for navigation properties
- ✅ Using TYPE_CHECKING for forward references
- ✅ Proper nullable handling with `| None` type unions

**References:**
- [SQLModel Documentation](https://sqlmodel.tiangolo.com/)
- [SQLAlchemy Relationships](https://docs.sqlalchemy.org/en/20/orm/relationships.html)
- [Python TYPE_CHECKING](https://docs.python.org/3/library/typing.html#typing.TYPE_CHECKING)

### Action Items

**✅ NO ACTION ITEMS REQUIRED**

All acceptance criteria met, all tasks verified complete, code quality excellent. Story is ready to merge.

**Advisory Notes:**
- Note: Consider renaming `Test` class to `TestModel` in future refactoring to avoid pytest collection warning (cosmetic only, not blocking)
- Note: The models are ready for use in STORY-032A (Repository refactoring)

---

**Change Log:**
- 2025-11-22: Senior Developer Review completed - APPROVED with no action items
