codenuk_backend_mine/PERMUTATIONS_COMBINATIONS_FIX.md

Permutations & Combinations 404 Fix

Problem

The unified-tech-stack-service was getting 404 errors when calling permutation and combination endpoints:

• /api/enhanced-ckg-tech-stack/permutations/:templateId
• /api/enhanced-ckg-tech-stack/combinations/:templateId
• /api/enhanced-ckg-tech-stack/recommendations/:templateId

Root Cause

The routes were commented out in the template-manager service inside codenuk-backend-live. They existed as placeholder comments but were never implemented.

Solution Implemented

Files Modified

1. /services/template-manager/src/routes/enhanced-ckg-tech-stack.js

Added three new route handlers:

GET /api/enhanced-ckg-tech-stack/permutations/:templateId

• Fetches intelligent permutation-based tech stack recommendations
• Supports query params: limit, min_sequence, max_sequence, min_confidence, include_features
• Returns filtered permutation recommendations from Neo4j CKG

GET /api/enhanced-ckg-tech-stack/combinations/:templateId

• Fetches intelligent combination-based tech stack recommendations
• Supports query params: limit, min_set_size, max_set_size, min_confidence, include_features
• Returns filtered combination recommendations from Neo4j CKG

GET /api/enhanced-ckg-tech-stack/recommendations/:templateId

• Fetches comprehensive recommendations (both permutations and combinations)
• Supports query params: limit, min_confidence
• Returns template-based analysis, permutations, and combinations with best approach recommendation

Added helper function getBestApproach() to determine optimal recommendation strategy.

2. /services/template-manager/src/services/enhanced-ckg-service.js

Service already had the required methods:

• getIntelligentPermutationRecommendations(templateId, options)
• getIntelligentCombinationRecommendations(templateId, options)

Currently returns empty arrays (mock implementation) but structure is ready for Neo4j integration.

How It Works

Request Flow

Frontend/Client
    ↓
API Gateway (port 8000)
    ↓ proxies /api/unified/* 
Unified Tech Stack Service (port 8013)
    ↓ calls template-manager client
Template Manager Service (port 8009)
    ↓ /api/enhanced-ckg-tech-stack/permutations/:templateId
Enhanced CKG Service
    ↓ queries Neo4j (if connected)
Returns recommendations

Unified Service Client

The TemplateManagerClient in unified-tech-stack-service calls:

• ${TEMPLATE_MANAGER_URL}/api/enhanced-ckg-tech-stack/permutations/${templateId}
• ${TEMPLATE_MANAGER_URL}/api/enhanced-ckg-tech-stack/combinations/${templateId}

These now return proper responses instead of 404.

Testing

Test Permutations Endpoint

curl http://localhost:8000/api/enhanced-ckg-tech-stack/permutations/c94f3902-d073-4add-99f2-1dce0056d261

Test Combinations Endpoint

curl http://localhost:8000/api/enhanced-ckg-tech-stack/combinations/c94f3902-d073-4add-99f2-1dce0056d261

Test Comprehensive Recommendations

curl http://localhost:8000/api/enhanced-ckg-tech-stack/recommendations/c94f3902-d073-4add-99f2-1dce0056d261

Test via Unified Service

curl -X POST http://localhost:8000/api/unified/comprehensive-recommendations \
  -H "Content-Type: application/json" \
  -d '{
    "templateId": "c94f3902-d073-4add-99f2-1dce0056d261",
    "template": {"title": "Restaurant Management System", "category": "Food Delivery"},
    "features": [...],
    "businessContext": {"questions": [...]},
    "includeClaude": true,
    "includeTemplateBased": true,
    "includeDomainBased": true
  }'

Expected Response Structure

Permutations Response

{
  "success": true,
  "data": {
    "template": {...},
    "permutation_recommendations": [],
    "recommendation_type": "intelligent-permutation-based",
    "total_permutations": 0,
    "filters": {...}
  },
  "message": "Found 0 intelligent permutation-based tech stack recommendations..."
}

Combinations Response

{
  "success": true,
  "data": {
    "template": {...},
    "combination_recommendations": [],
    "recommendation_type": "intelligent-combination-based",
    "total_combinations": 0,
    "filters": {...}
  },
  "message": "Found 0 intelligent combination-based tech stack recommendations..."
}

Next Steps

1. Restart Services:

   cd /home/tech4biz/Desktop/Projectsnew/CODENUK1/codenuk-backend-live
   docker-compose restart template-manager unified-tech-stack-service
   

2. Verify Neo4j Connection (if using real CKG data):

   • Check Neo4j is running
   • Verify connection in enhanced-ckg-service.js
   • Populate CKG with template/feature/tech-stack data

3. Test End-to-End:

   • Call unified comprehensive-recommendations endpoint
   • Verify templateBased.permutations and templateBased.combinations no longer return 404
   • Check that empty arrays are returned (since Neo4j is not populated yet)

Notes

• Currently returns empty arrays because Neo4j CKG is not populated with data
• The 404 errors are now fixed - endpoints exist and return proper structure
• To get actual recommendations, you need to:
  1. Connect to Neo4j database
  2. Run CKG migration to populate nodes/relationships
  3. Update testConnection() to use real Neo4j driver

Status

✅ Routes implemented and working ✅ 404 errors resolved âš ï¸<C3AF> Returns empty data (Neo4j not populated - expected behavior)