feat(elm): Phase 2 Review, Test and Improvement of ELM Module (Roll 24BCS260,24BCS222)

[uttkarshbagad]

Employee Leave Management (ELM) — Phase 2 Implementation

1. Student Details

• Roll Number: 24BCS260
• Roll Number: 24BCS222

2. Environment & Model Configuration

• Model: Qwen2.5-Coder:7b (7.6B parameters, Q4_K_M quantization)
• Inference Runtime: Ollama
• Coding Interface: Continue VS Code Extension (Chat mode with @file context)
• Hardware: Apple MacBook Air (M3, 16 GB Unified Memory)

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3. Summary of Improvements Made in Phase 2

1. Models & Schema Alignment (modules/elm/models.py):
   • Added reason field to LeaveApplication.
   • Updated STATUS_CHOICES to include multi-step workflow states (AWAITING_SUBSTITUTE, AWAITING_APPROVAL, APPROVED, REJECTED, WITHDRAWN, CANCELLED).
   • Added status (PENDING, ACCEPTED, DECLINED) and decline_reason to SubstituteNomination.
2. Domain Business Rules (modules/elm/domain/policy.py):
   • Implemented pure-Python rules for date overlap prevention (BR-EL-012), self-substitute prevention (BR-EL-014), balance sufficiency, and state transition validation.
3. Service Layer (modules/elm/services/applications.py):
   • Integrated atomic transactions, balance validation, overlap checks, substitute consent handling, and supervisor review with balance deduction.
4. Database Migration (modules/elm/migrations/0002_add_workflow_and_reason_fields.py):
   • Created schema migration to persist the updated models.
5. Automated Unit Testing (modules/elm/tests/test_policy.py):
   • Established automated pytest suite covering all domain rules (100% pass rate).
6. REST API Layer (modules/elm/api/):
   • Wired serializers, views, and routes for applications, substitute responses, reviews, and withdrawals.
7. Frontend Client (client/src/modules/elm/):
   • Replaced UI stubs with live data fetching in LeaveBalance.tsx and form submission with error feedback in LeaveApplication.tsx.

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4. Detailed Engineering & Code Review Log

For the complete step-by-step log containing exact prompts, AI outputs, and defects caught during human-in-the-loop review, please see:
👉 docs/changes_made_by_24bcs260.md

[uttkarshbagad]

Summary of Phase 2 Improvements (ELM Module)

This PR implements the Phase 2 review, testing, correction, and enhancement of the Employee Leave Management (ELM) module inherited from Phase 1 (elm-pilot-qwen), adhering strictly to the ELM Specification Bundle v1.4, clean domain architecture, and the human-in-the-loop local AI prompting workflow.

Engineering & Review Log

A detailed record of all local AI (qwen2.5-coder:7b) prompts, human code review findings, runtime defects caught, and applied fixes is documented here:
👉 ELM Phase 2 Engineering Log (Roll 24BCS260)

Key Commits Included:

• e4afea2: feat(elm): update models with workflow statuses and reasons (added reason, workflow state choices, substitute consent status)
• 9e9507e: feat(elm): add pure-Python domain business rules and transition validators (BR-EL-012 date overlap, BR-EL-014 substitute eligibility, balance sufficiency)
• ae43983: feat(elm): integrate domain rules and workflow actions into application service (atomic transactions, balance deductions, substitute workflow)
• 916bed9: feat(elm): add schema migration for workflow statuses and reasons (Django migration 0002)
• 937b9dc: test(elm): add automated pytest suite for domain policy business rules (100% passing domain unit tests)
• fa0e6a3: feat(elm): wire complete REST API views, serializers, and routes (endpoints for submit, substitute response, review, withdraw)
• 4d1a882: feat(elm): wire LeaveBalance and LeaveApplication frontend to REST API (connected React components to live API)
• 7809065: docs(phase2): organize engineering log by commit hashes