Thank you for interest in ChomCHOB

We have 2 part for testing your coding skill. When you done this task you need to created repository like in "example submission" folder on your github repository.

This test contain with 2 part.

1. Programming
2. Database

• You have 7 day after receive email to complete this test.

Description

You need to create simple wallet api for transfer cryptocurrency between user A to user B. Also have admin ability to manage both cryptocurrency and exchange rate.

Requirement

• Admin can increase and decrease user cryptocurrency balance.
• Admin can see all total balance of all cryptocurrency.
• Admin can add other cryptocurrency such XRP, EOS, XLM to wallet.
• Admin can manage exchange rate between cryptocurrency.
• User can transfer same cryptocurrency to other.

Example

UserA transfer 10 ETH to UserB so UserB will recieve 10 ETH

• User can transfer cryptocurrency to other with difference currency such ETH to BTC with exchange rate.

Example

UserA transfer 1000 ETH to UserB with exchange rate ETH/BTC equal to 0.05 so UserB will recieve 50 BTC

• It ok whether cryptocurrency have decimal or not.

Technical Detail

• This API need to be written with Nodejs.
• You can use any nodejs web framework but we prefer express.
• You can use any tool or library to help you build API.
• Database we prefer mariadb, but if you think other database is suitable it fine to use that db.
• Please provide us POSTMAN collection and environment(if needed) in JSON format.
• This is not decentralized wallet so no need to worry about blockchain stuff.
• If some of detail or requirement are ambiguous, we so sorry about that. And feel free to use your creative thinking to do that stuff.

Bonus

• TDD
• Deploy to cloud such as aws or gcp.

You have assign to design Database for sale item code system for game this provide for customer who want to buy code for using in game.

Detail

• Item for sale must have product name, product detail, sale price, open sale date, end sale date.
• When customer already bought an item, customer will receive code (code can be created or create after bought).
• item have a discount promotion period with specific date time for example normal price is 150 baht and have a promotion on January and set discounted price to 100 baht.

Bonus

• item may sale in bundle type for example sale two difference character skin set in special price or sale five gachapon box (for random item) in special price.

Objective

• Create database in form of model from sequelize.
• Create Entity Relationship Diagram (ERD) and provide us with picture or pdf format. You can create ERD with any tool you want even handwriting is fine.
• Please provide us description why you design database like this, for clearly understand.

Example Sequelize Model

// Store User
const User = sequelize.define('User', {
  id: Sequelize.INTEGER,
  name: Sequelize.STRING,
  age: Sequelize.INTEGER,
})

User.associate = (models) => {
  User.hasMany(UserCard, { foreignKey: 'user_id' })
}

// Store User credit card 
const UserCard = sequelize.define('UserCard', {
  id: Sequelize.INTEGER,
  user_id: Sequelize.INTEGER,
  mask_pan: Sequelize.STRING,
})

UserCard.associate = (models) => {
  UserCard.belongsTo(User, { foreignKey: 'user_id' })
}

Example Entity Relationship Diagram

Hint

• You can see database part in thai language for better understanding.