STI Phase 5: Quick Reference Summary

Document Overview

• Location: STI_PHASE5_ANALYSIS.md (953 lines, 27KB)
• Purpose: Complete analysis of error handling and documentation for STI Phase 5
• Status: All phases 1-4 complete, ready for Phase 5 implementation

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Current Implementation Status

Error Handling ✅ (Partial)

Error Scenario	Status	Location	Issue
Missing _meta_type on load	✅ Implemented	object.ts:380	Uses plain Error
Type mismatch on load	✅ Implemented	object.ts:388	Uses plain Error
Missing _meta_type on save	✅ Implemented	object.ts:745	Uses plain Error
_meta_type mismatch on save	✅ Implemented	object.ts:751	Uses plain Error
STI base not found	✅ Implemented	schema/utils.ts:88	Uses plain Error
Class not in registry	✅ Implemented	collection.ts:777	Uses plain Error
WHERE clause validation	⚠️ Partial	collection.ts:48	Missing _meta_type value validation
Corrupted _meta_data	❌ Missing	object.ts:402	Can crash on JSON parse
Circular inheritance	❌ Missing	registry.ts	Can cause infinite recursion
Mixed STI/CTI	❌ Missing	registry.ts	Data corruption risk

Documentation 📚 (Minimal)

Topic	Status	Location	Gap
Code comments	✅ Good	object.ts, collection.ts, schema/utils.ts	Scattered, not consolidated
Test examples	✅ Basic	sti-polymorphic-queries.test.ts	Limited to basic scenarios
README examples	❌ None	README.md	No STI examples
Getting started	❌ None	—	No tutorial
Best practices	❌ None	—	No guidelines
Meta fields	❌ None	—	No dedicated guide
Migration guide	❌ None	—	No CTI→STI docs
Troubleshooting	❌ None	—	No error docs
API reference	❌ None	—	@smrt() options undocumented
Performance	❌ None	—	No guidelines

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Critical Error Scenarios (Must Fix)

1. Corrupted _meta_data JSON (CRASH RISK)

// Current code (object.ts:402) - NO ERROR HANDLING
const metaData = typeof data._meta_data === 'string'
  ? JSON.parse(data._meta_data)  // ← Can throw SyntaxError!
  : data._meta_data;

Solution: Wrap in try-catch, throw DatabaseError

2. Circular Inheritance (INFINITE RECURSION RISK)

// NOT CAUGHT - Can cause infinite loops
@smrt({ tableStrategy: 'sti' })
class A extends B {}

@smrt()
class B extends A {}  // ← Circular!

Solution: Add cycle detection in ObjectRegistry.register()

3. Mixed STI/CTI Strategies (DATA CORRUPTION RISK)

// NOT CAUGHT - Leads to confused table layouts
@smrt({ tableStrategy: 'cti' })
class Parent extends SmrtObject {}

@smrt({ tableStrategy: 'sti' })
class Child extends Parent {}  // ← Conflicting!

Solution: Add strategy compatibility validation

4. NULL _meta_type (SILENT DATA ISSUES)

// Current: Uses falsy check (null passes!)
if (!data._meta_type) {  // ← null is falsy but NOT caught!
  throw new Error(...);
}

// Should be:
if (data._meta_type === null || data._meta_type === undefined) {
  throw ValidationError.requiredField('_meta_type', className);
}

5. Base Class Not Registered (POLYMORPHIC QUERY FAILURES)

// NOT CAUGHT
class Event extends SmrtObject {}  // ← No @smrt()!

@smrt()
class Meeting extends Event {}

// Polymorphic query fails silently when trying to load Event type
const event = await eventCollection.get(eventId);

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Documentation Structure Needed

New Files Required

1. docs/STI.md - Complete STI guide
2. docs/META-FIELDS.md - Meta field documentation
3. docs/STI-MIGRATION.md - CTI to STI migration guide
4. examples/sti/ - Working code examples

Existing Files to Update

1. CLAUDE.md - Add STI section with examples
2. README.md - Add STI overview with link to guide

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Implementation Priority

Phase 5a - CRITICAL (Do First)

Error Handling:

• ✅ Convert plain Error → typed error classes
• ✅ Add JSON parse safety
• ✅ Add cycle detection
• ✅ Add strategy validation

Documentation:

• ✅ Create STI.md guide
• ✅ Create META-FIELDS.md guide
• ✅ Update CLAUDE.md

Phase 5b - HIGH VALUE (Do Next)

Error Handling:

• ✅ Base class registration validation
• ✅ _meta_type value validation in WHERE
• ✅ Deep inheritance warnings

Documentation:

• ✅ Create migration guide
• ✅ Create troubleshooting section
• ✅ Add code examples

Phase 5c - FUTURE (Later)

• ✅ Schema mismatch detection
• ✅ Performance warnings
• ✅ Query optimization docs

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Quick Stats

Metric	Value
Implemented error scenarios	4 (+ 1 partial)
Missing critical error scenarios	10
Error types used	1/6 (plain Error)
Documentation sections	0 dedicated
Code comment locations	4+ files
Test examples	2 test files
Realistic usage examples	4 (in analysis)
Recommended implementations	9+
Lines of analysis	953
Code examples in analysis	10+

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How to Use This Analysis

1. Read the full document: STI_PHASE5_ANALYSIS.md
2. Review error scenarios: Part 1 details what's implemented vs missing
3. Review documentation gaps: Part 2 shows what's missing
4. Check implementation templates: Part 3 provides code examples
5. Review documentation structure: Part 4 shows what to create
6. Use the examples: Part 5 provides realistic scenarios
7. Follow the roadmap: Part 6 suggests implementation order

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Key Takeaways

What's Working Well ✅

• Core STI implementation is solid (4 error checks + validation)
• Polymorphic queries working correctly
• Meta field support complete
• Schema generation for STI tables correct
• Test coverage for basic scenarios

What Needs Work ⚠️

• Error types not using framework classes (using plain Error)
• Missing critical error scenarios (circular inheritance, corrupted data)
• Documentation scattered or missing
• No guides for users
• No migration strategy

Next Steps 🚀

1. Implement Phase 5a error handling
2. Create core documentation files
3. Add examples and use cases
4. Create migration guide
5. Build troubleshooting section

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File Locations Reference

Source Code

• Error handling: src/object.ts, src/collection.ts, src/schema/utils.ts
• Error classes: src/errors.ts
• Registry: src/registry.ts
• Fields: src/fields/index.ts

Tests

• STI tests: src/__tests__/sti-*.test.ts
• Other tests: src/__tests__/inheritance*.test.ts

Documentation

• Framework docs: CLAUDE.md
• README: README.md
• Analysis: STI_PHASE5_ANALYSIS.md (this file's source)

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Generated: 2025-11-11 Version: Phase 5 Analysis Complete Status: Ready for Implementation