ticketing_app

Ticket reselling app created using microservices architecture

Technologies:

• React (Frontend)
• Typescript and Express - creating an npm library (Backend)
• MongoDB and Redis (Database)
• Next.js (Framework)
• Docker, Kubernetes, NATS streaming server (Infrastructure)
• Google Cloud (remote environment) [optional]

Global Dependencies

• cookie-session

Features

• Users can list a ticket for an event for sale
• Other users can purchase this ticket
• Any user can list tickets for sale and purchase tickets
• When a user attemps to purchase a ticket, the ticket is 'locked' for 15 minutes
• While 'locked', no other user can purchase that ticket
• Ticket prices can be edited if they are not locked

Resource Types

User
email	string
password	string

Ticket
title	string
price	number
userId	reference to User
orderId	reference to Order

Order
userId	reference to User
status	created/cancelled/awaitingPayment/completed
expiresAt	Date
ticketId	reference to ticket

Charge
orderId	reference to Order
status	created/failed/completed
amount	number
stripeId	string
stripeRefundId	string

Service Types

Name	Desc
auth	all signup/in/out
tickets	controls creation, editing, and ticket update logic
orders	creating and editing orders
expiration	monitors order time (default 15mins), after which an order is cancelled
payments	responsible for charges via stripe

Event types

• UserCreated UserUpdated
• OrderCreated OrderCancelled OrderExpired
• TicketCreated TicketUpdated
• ChargeCreated

GoogleCloud

• notes on remote setup here

Testing in Microservices

• Using Jest - with command npm run test.
• Make fake requests with supertest library.

Scope:

• Test a single piece of code in isolation - e.g. Unit Tests for individual middleware
• Test how different pieces of code work together e.g. from one middleware to routehandler
• Test how different components work together e.g. testing microservice
• Test how different microservices work togehter e.g. how orders service works with ticketing service

Test Goals

• Basic Request Handling
• Unit Tests for database Models
• Event emitting and receiving

Flow for creating each service

• Create package.json with npm init -y and install dependencies
• Write Dockerfile
• Create index.ts as entry point for project
• Build docker image and push to docker hub
• Write k8s file for deployment and service(s) e.g. ClusterIP
• Update skaffold.yaml for development update syncing
• Write k8s file for MongoDB deployment and service e.g. ClusterIP