Add per-agent mutex using promise chaining to serialize state transitions
for the same agent. This prevents the Time-of-Check-Time-of-Use race
condition where two concurrent requests could both read the current state,
both validate it as valid for transition, and both write, causing one to
overwrite the other's transition.
The mutex uses a Map<string, Promise<void>> with promise chaining so that:
- Concurrent transitions to the same agent are queued and executed sequentially
- Different agents can still transition concurrently without contention
- The lock is always released even if the transition throws an error
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Add removeSession and scheduleSessionCleanup methods to AgentSpawnerService
- Schedule session cleanup after completed/failed/killed transitions
- Default 30 second delay before cleanup to allow status queries
- Implement OnModuleDestroy to clean up pending timers
- Add forwardRef injection to avoid circular dependency
- Add comprehensive tests for cleanup functionality
Refs #338
Implemented three new API endpoints for knowledge graph visualization:
1. GET /api/knowledge/graph - Full knowledge graph
- Returns all entries and links with optional filtering
- Supports filtering by tags, status, and node count limit
- Includes orphan detection (entries with no links)
2. GET /api/knowledge/graph/stats - Graph statistics
- Total entries and links counts
- Orphan entries detection
- Average links per entry
- Top 10 most connected entries
- Tag distribution across entries
3. GET /api/knowledge/graph/:slug - Entry-centered subgraph
- Returns graph centered on specific entry
- Supports depth parameter (1-5) for traversal distance
- Includes all connected nodes up to specified depth
New Files:
- apps/api/src/knowledge/graph.controller.ts
- apps/api/src/knowledge/graph.controller.spec.ts
Modified Files:
- apps/api/src/knowledge/dto/graph-query.dto.ts (added GraphFilterDto)
- apps/api/src/knowledge/entities/graph.entity.ts (extended with new types)
- apps/api/src/knowledge/services/graph.service.ts (added new methods)
- apps/api/src/knowledge/services/graph.service.spec.ts (added tests)
- apps/api/src/knowledge/knowledge.module.ts (registered controller)
- apps/api/src/knowledge/dto/index.ts (exported new DTOs)
- docs/scratchpads/71-graph-data-api.md (implementation notes)
Test Coverage: 21 tests (all passing)
- 14 service tests including orphan detection, filtering, statistics
- 7 controller tests for all three endpoints
Follows TDD principles with tests written before implementation.
All code quality gates passed (lint, typecheck, tests).
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
