M. Tahsin Anwar

A multi-role-based eCommerce platform built from scratch.

Tech: Node.js, Express, MongoDB, React, Redux.

User Features:
• Login, register
• Add products to their cart
• Check them out with shipping address and payment info
• Place the order, pay for the order using PayPal/credit card
• Update their profile and see their orders' details only
• Review/rate a product once only to avoid BOT/spam reviews

Admin Features:
• Login
• Perform all that a user can perform
• Create/update/delete a product
• Update/delete a user
• Mark a user to be an admin user
• See all users' order details
• Mark the delivered orders as delivered

Additional Functionalities:
• Top products carousel
• Product pagination
• Product search
• Database seeder (products and users)
• Server deployment support (Heroku)

Live URL: https://proshop-9999.herokuapp.com

A form generator app to populate or download PDF/DOCX forms with some specific data from Google Sheets, as well as from some fields of the application. This is developed for internal employees of the company.

FEATURES
• Users can upload sample PDF/DOCX templates with proper data mapping. The application will generate the filled forms properly and the placeholders are mentioned in the README.
• Users can remove existing PDF/DOCX templates that may be discontinued or are redundant.
• An internal scheduler has been configured to remove the obsolete files (removed by users or downloaded ones) after every seven days to minimize the server's storage space.
• Proper form validations, exception handlings, and success/error notification toasts are also implemented.

A back-end API for multi-role-based DevCamper application, a boot camp directory website.

Tech: Node.js, Express, MongoDB

Bootcamp Features
• List all boot camps and also within a radius specifying zip code and covering the distance
• CRUD over a boot camp with proper authorization
• Upload a photo for boot camp with proper authorization

Course Features
• List all courses and for a boot camp
• CRUD over a course with proper authorization

Review Features
• List all reviews and for a boot camp
• CRUD over a review with proper authorization

User Features
• List all users
• CRUD over a user with proper authorization

Auth Features
• User login, registration, and logout
• Preview my profile
• Update my profile/password
• Forget/reset the password

Misc Features:
• JWT Auth
• Miscellaneous filters, pagination, selection, sorting; addition for listers
• Mongoose and other validations
• DB seeders
• Prevent NoSQL injections
• Add security headers, prevent XSS
• Rate Limiter (100 requests per 10 minutes per user)
• HTTP param polution protection
• CORS to make API public
• API doc in Postman and by Docgen
• DigitalOcean deployment

Live URL: http://159.223.10.250/

Postman Doc: https://documenter.getpostman.com/view/2647947/UzJQqZwk

Back-end API for the Task Manager application, where users can CRUD over their tasks and admins can also manage all the tasks and the users.

Tech: Node.js, Express, MongoDB

Task Features
• List logged-in user tasks, all users' tasks (i.e., by admin)
• Save, update, and delete a task for the logged-in user, or other users (i.e., by admin)

User Features:
• List all users with proper authorization
• Create, update, and delete a user with proper authoirzation
• View and upload a user's profile photo, save it in bytes

Auth Features:
• User Login, logout, and registration (with a user role)
• Preview and update my profile
• Update, forget, and reset password
• View or upload profile photo, save it in bytes

Misc Features:
• JWT authorization
• Password hashing
• Mongoose and other validations
• Database seeders
• Prevent NoSQL injections
• Add security headers
• Prevent XSS
• Rate Limiter (100 requests per 10 minutes for a user)
• HTTP param polution protection
• CORS to make API public
• API documentation in Postman and by Docgen
• DigitalOcean deployment

Live URL/Docgen: http://188.166.97.45/
Postman: https://documenter.getpostman.com/view/2647947/UzQuR6nt

An online soccer manager game where users can create fantasy teams and will be able to sell and buy players among them.

Tech: Java, Spring Boot, Hibernate, MySQL

Game Features and Rules
• Users can create an account and log in using the API.
• Each user can have only one team.
• When the user is signed up, they get a team of 20 players (system generated).
• Each player has an initial value of $1,000,000.
• Each team has an additional $5,000,000 to buy other players.
• When logged in, a user can see or update only their team and player information.
• A team owner can set the player on a transfer list.
• When a user places a player on a transfer list, they set the asking price/value for this player. This value is listed on a market list.
• When another user or team buys this player, they must be purchased for this price.
• Each user can see all players on a transfer list.
• With each transfer, team budgets and values are updated.
• With each transfer, the player's price is increased by a certain factor.

This is a multi-role-based online doctor booking management application with a custom automated scheduling approach where doctors can:
• Enroll themselves and update only their profile.
• View, update, and delete their appointments.
• Create their specialty field if not found in database.

Patient Features:
• Enroll themselves and update only their profile.
• View all available doctors.
• View, create, and delete their appointments with available doctors.
• Automatically generate their appointment date/time.
• Create an appointment with a specific date/time if valid/available for that doctor.
• Cannot view other patients or others' appointments (i.e., HIPAA violation).

Admin Features:
• Enrolled only by super admin and cannot register/update his profile.
• Can perform all of super admin's tasks except for viewing and updating the role actions of anyone or CRUD over admins.

Super Admin Features:
• Cannot CRUD over himself, already created by a developer using SQL.
• CRUD over doctors/patients/admins/specialties/appointments.
• Update role actions of role types (i.e., doctor/patient/admin).
• Block users of a specific role type from performing a particular role action.

Tech: Java, Spring MVC, Hibernate, JSP.

An IBAN (International Bank Account Number) document validator app where the user can send a .doc/.docx/.pdf file to the server and validate whether it contains any blocklisted or invalid IBAN.

As an API consumer, the user or admin can send a local file or remote URL and file type, which will save the fetched file in the server-local storage. It would also send the whole file as a message through Kafka.

The sent file is asynchronously validated through the server's Kafka listener. openiban API has been used to validate the IBAN inside the file. After sending the result JSON with proper validations, the locally kept file in the server is deleted using another Kafka listener.

A simple weather checking app where an API consumer can:
• Search for today's weather by inputting the city name.
• Look for weather data from past periods.
• Look for earlier saved weather data for a specific city with or without mentioning the generation date.
• Look for the latest saved weather data for a specific city.
• Save weather data for retrieval.
• Locally save the current weather data for a specific city for later retrieval.
• Update an existing weather record.
• Delete an existing weather record.

Implemented a custom @Size annotation with proper validators. Users can use this on different properties to define or validate the range of a given input. Unlike the JSR provided @Size annotation, it can also support these data types along with string: integer, long, collection (i.e., validating the size).