Leave Management System

A Leave Management System built with React, Node.js, Express, and MySQL. It supports multi-role architecture: Employee, Manager, HR, and Admin, with features like multi-level approvals, real-time calendar view of team leaves, Redis queueing for bulk operations, and detailed leave policies and balances.

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🚀 Features

👥 User Roles

• Employee, Manager, HR:
  • Submit leave requests
  • View leave balance and history
  • Cancel leaves
  • Change their password
• Manager, HR:
  • View incoming leave requests from their team
  • Approve or reject leave requests
  • View team leave calendar
• Admin:
  • Full access to leave requests and approvals
  • Manage users and leave types/policies
  • View who's on leave today
  • Upload users in bulk using Redis and Bull
  • Approve/Reject as per special criteria

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📅 Functional Modules

• ✅ Multi-level leave approval workflow
• 📊 Accurate leave balance tracking with used, remaining, and max limits
• ❌ Overlapping leave prevention
• 📦 Bulk user upload with Redis + Bull
• 📆 Calendar UI to visualize team leave status
• 🔐 Password update capability
• 🧭 Role-based access control with middleware
• 🔁 Reusable Express middleware for authentication and role checking

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🧩 Database Schema Overview

• users – User details
• roles – Defines available roles
• leave_requests – Leave submissions
• leave_approvals – Tracks each level of approval
• leave_types – Types of leaves
• leave_policies – Policy metadata
• leave_balances – Tracks current leave balances and used leaves per user

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📦 API Routes

🔐 Authentication & Users

• POST /login – Login as a user
• POST /register – [Admin only] Register a new user
• GET /users – [Admin only] Fetch all users
• POST /upload-users – [Admin only] Bulk upload users using Excel + Redis
• PUT /password/:userId – Update user password

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📝 Leave Requests

• POST /request – Submit a leave request
• PUT /cancel/:leaveRequestId – Cancel a submitted leave
• GET /history/:userId – Get leave history for a user
• GET /requests/history/:userId – Get all requests submitted by the user

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📊 Leave Balance

• GET /balance/:userId – Get leave balance for a specific user

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✅ Leave Approvals

• GET /requests/:userId – View incoming leave requests (Manager, HR, Admin)
• PUT /approve/:approveId – Approve a pending leave
• PUT /reject/:rejectId – Reject a pending leave

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🗂️ Leave Types & Policy Management

• GET /types/:userId – Fetch leave types applicable to the user’s role
• GET /types – Fetch all leave types
• POST /types – [Admin only] Create a new leave type
• PUT /types/:id – [Admin only] Update a leave type
• DELETE /types/:id – [Admin only] Delete a leave type

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🗓️ Admin & Team

• GET /on-leave-today – [Admin only] List users on leave today
• GET /team-leaves – View team leave status in a calendar-style view

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🧪 Tech Stack

💻 Frontend

• React.js
• React Router for navigation
• Recharts for charts
• Custom calendar and dashboard components

🖥️ Backend

• Node.js + Express.js
• MySQL + TypeORM (ORM)
• Redis + Bull for queueing (bulk uploads)
• Role-based access control
• Middleware-based authentication using JWT

🗃️ Database

• MySQL:
  • Normalized structure
  • Support for multi-approver workflows
  • Optimized indexes and relations

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⚙️ Database Setup with Auto Seeder

This project includes seeder scripts, so when you run the backend with synchronize: true enabled in your TypeORM configuration:

• You just need to create a db and mention that in env
• All required tables will be created automatically
• Initial data like roles, leave types, and default admin user will be inserted automatically