Syed Jafer K

Its all about Trade-Offs

Inventory and Order Management System – MongoDB Capstone Project – MDB-P-002

Overview

The Inventory and Order Management System is an end-to-end MongoDB project focused on managing products, suppliers, and customer orders. It covers all aspects of database management, from CRUD and validation to indexing, replication, and disaster recovery. The goal is to simulate how an e-commerce backend or retail management system would handle real-world data consistency and durability challenges.

Database Design

The project consists of three primary collections — products, suppliers, and orders.
The products collection keeps details like product name, category, price, stock quantity, and update timestamp.
The suppliers collection stores information about supplier name, contact, and region.
The orders collection captures order details such as product ID, customer name, quantity, date, and order status.
Relationships are maintained through references between products and orders, allowing efficient lookups and analytics.

CRUD Operations

The CRUD layer enables administrators to add new products, update stock levels, record customer orders, and remove obsolete entries. For example, every time a new order is placed, the corresponding product’s stock count is automatically reduced. This step reinforces how MongoDB’s document model simplifies transactional workflows for real-world inventory management.

Schema Validation

The project enforces schema validation rules to maintain data quality. Constraints ensure that fields like price and stock are non-negative and that essential attributes like product name are always present. This introduces schema enforcement in a NoSQL database while retaining flexibility.

Indexing and Query Optimization

Indexing strategies are designed to improve query efficiency for frequent operations such as fetching products by category or filtering orders by date. Learners experiment with single-field, compound, and text indexes to understand their impact on performance and how the query planner chooses index paths.

Aggregation Framework

Aggregation pipelines are used to compute total sales per product, total revenue by category, and low-stock alerts. Learners practice building multi-stage pipelines that join collections, calculate totals, and return meaningful insights for business decisions.

Transactions and Consistency

The project showcases how MongoDB handles concurrent updates, ensuring that inventory and order data remain consistent. Transactions are demonstrated when multiple collections must be updated atomically — such as creating an order and adjusting stock at the same time.

Replication for High Availability

Replication is configured to protect against hardware or node failures. A three-node replica set demonstrates how MongoDB replicates data across nodes and automatically promotes a secondary node to primary if the main one fails. Learners observe how this architecture improves uptime and provides read scalability.

Backup and Restore

Backups are taken regularly using logical export tools. This demonstrates how to plan and test database recovery using backups. The restore process is tested by intentionally deleting and restoring data, ensuring a complete understanding of backup validation and restoration workflows.

Point-in-Time Recovery (PITR)

Using the replication oplog, learners implement point-in-time recovery to restore the system to a specific moment before data corruption or accidental deletion occurred. This hands-on exercise introduces disaster recovery planning and the concept of Recovery Time Objective (RTO) versus Recovery Point Objective (RPO).

Snapshot and Disaster Simulation

Filesystem or volume-level snapshots are used to capture instant backups of the MongoDB data directory. Students learn how snapshots differ from logical backups and how they can be used for faster restores during system failures or ransomware-like scenarios. A simulated disaster scenario is created to test full restoration using snapshots.

Monitoring and Profiling

To ensure smooth operation, the system uses monitoring tools that track performance, replication lag, and query execution times. Profiling is enabled to analyze slow queries and optimize index design. These tools collectively teach proactive database maintenance and performance tuning.

Optional Advanced: Sharding

As an optional step, the project can be scaled horizontally by implementing sharding on the orders collection. Sharding based on region or customer name demonstrates how MongoDB handles distributed data across multiple servers while maintaining query performance.

API Structure

1. Product Management APIs

PurposeEndpointMethodDescription
Add product/api/productsPOSTCreate a new product with name, category, price, and stock.
Get all products/api/productsGETList all products, optionally filtered by category or price range.
Get product by ID/api/products/{id}GETFetch detailed product info.
Update product/api/products/{id}PUTUpdate stock, price, or description.
Delete product/api/products/{id}DELETEPermanently remove a product.

2. Supplier Management APIs

PurposeEndpointMethodDescription
Add supplier/api/suppliersPOSTCreate a new supplier with name, contact, and region.
Get suppliers/api/suppliersGETRetrieve all suppliers.
Get supplier by ID/api/suppliers/{id}GETFetch supplier details and linked products.
Update supplier/api/suppliers/{id}PUTModify supplier information.
Delete supplier/api/suppliers/{id}DELETERemove a supplier record.

3. Order Management APIs

PurposeEndpointMethodDescription
Place new order/api/ordersPOSTCreate a new order and automatically reduce stock.
Get all orders/api/ordersGETRetrieve all orders with optional filters (date, status, product).
Get single order/api/orders/{id}GETView full order details.
Update order status/api/orders/{id}PUTModify status (e.g., pending, shipped, delivered).
Cancel order/api/orders/{id}DELETEDelete or cancel an existing order.

4. Reports & Insights APIs

PurposeEndpointMethodDescription
Sales by product/api/reports/sales-by-productGETShow total revenue per product.
Sales by category/api/reports/sales-by-categoryGETAggregate sales grouped by category.
Low stock alert/api/reports/low-stockGETIdentify products with critical inventory levels.
Supplier performance/api/reports/supplier-performanceGETAnalyze suppliers based on delivery and product stats.

5. Backup, Restore & PITR APIs

PurposeEndpointMethodDescription
Initiate backup/api/admin/backupPOSTTrigger data backup operation.
Restore data/api/admin/restorePOSTRestore inventory system from the latest backup.
Create snapshot/api/admin/snapshotPOSTSimulate snapshot capture.
Perform PITR/api/admin/pitrPOSTRollback data to a particular timestamp.
Backup logs/api/admin/backup-logsGETDisplay backup history and restore events.

6. Replication & Monitoring APIs

PurposeEndpointMethodDescription
Replica set info/api/admin/replica-statusGETShow replication health and node roles.
Performance metrics/api/admin/performanceGETReturn read/write performance statistics.
Health check/api/healthGETSimple readiness probe to confirm database availability.

7. Optional Sharding & Scaling APIs

PurposeEndpointMethodDescription
Shard status/api/admin/shard-statusGETDisplay current shard distribution.
Move chunk/api/admin/shard-migratePOSTSimulate shard migration between nodes.
Balancer control/api/admin/shard-balancerPUTEnable or disable balancer for testing chunk movement.

By completing this project, learners develop a complete understanding of how MongoDB powers real-world business systems. They gain practical experience in designing schemas, implementing CRUD operations, performing aggregations, ensuring high availability, planning disaster recovery, and monitoring performance. The project mirrors production-grade design principles, giving a holistic view of MongoDB administration and data engineering.