WALLETS API

In this project, we're set up a simple Rails API-only-application. Rails API-only-applications are slimmed down compared to traditional Rails web applications.

Built With

• Ruby v2.7.2
• Ruby on Rails v7.0.0.alpha2
• RSpec-Rails for testing

Current API Endpoints

The API will expose the following RESTful endpoints.

BaseUrl: {Host-URL}/api/v1

Endpoint	Functionality
GET /api/v1/users/:id/balance	Check wallet balance
POST /api/v1/users/:id/deposit	Deposit money into wallet
POST /api/v1/users/:id/transfer	Transfer money to another user
POST /api/v1/users/:id/withdraw	Withdraw money from wallet

To get a local copy up and running follow these simple example steps.

Prerequisites

Ruby: 2.7.2 Rails: 7.0.0.alpha2 Postgres: 14.0

Model

Setup

# unzip crypallet.zip
$ cd crypallet

Install gems with:

$ bundle install

Setup database with:

make sure you have postgress sql installed and running on your system

$ rails db:create
$ rails db:migrate
$ rails db:seed

Dbdiagram

https://dbdiagram.io/d/6183064ed5d522682df795f8

Usage

Start server with:

$ rails server

Open Insomnia or Postman API request tool.

Check wallet balance

1. Path: /api/v1/users/1/balance
2. Method: GET
3. Headers:
   • Accept: application/json
   • Content-Type: application/json
4. Response:
   • Status: 200
   • Body:
     • { "balance": 9500 }
5. Errors:
   • [404] :not_found
   • [422] :unprocessable_entity

Deposit money into wallet

1. Path: /api/v1/users/1/deposit
2. Method: POST
3. Headers:
   • Accept: application/json
   • Content-Type: application/json
4. Request body:
   • { "amount": 1000 }
5. Response:
   • Status: 200
   • Body:
     • { "balance": 9500 }
6. Errors:
   • [404] :not_found
   • [422] :unprocessable_entity

Transfer money to another user

1. Path: /api/v1/users/1/transfer
2. Method: POST
3. Headers:
   • Accept: application/json
   • Content-Type: application/json
4. Request body:
   • { "amount": 500, "to_user_id": 2 }
5. Response:
   • Status: 200
   • Body:
     • { "balance": 9000 }
6. Errors:
   • [404] :not_found
   • [422] :unprocessable_entity

Withdraw money from wallet

1. Path: /api/v1/users/1/withdraw
2. Method: POST
3. Headers:
   • Accept: application/json
   • Content-Type: application/json
4. Request body:
   • { "amount": 500 }
5. Response:
   • Status: 200
   • Body:
     • { "balance": 9000 }
6. Errors:
   • [404] :not_found
   • [422] :unprocessable_entity

Run tests

$ rpsec

Highlight code

The core of the project is the User controller. The User controller is responsible for the balance and deposit and withdraw and transfer action.

Improvement

1. Need to add token verify for each api call.
2. Loading test with large traffic.
3. Pessimistic locking may cause performance issue.