Voting application with 2 Load Balanced Web Services, Backend Service, and RDS!

[efekarakus]

The "voting-app" can be used as inspiration for defining an application composed of multiple services behind a load balancer communicating with an API that fronts a SQL database.

Background

The https://github.com/copilot-example-voting-app application satisfies the following architecture:

It is composed of three different microservices:

• The "vote" load balanced web service: https://github.com/copilot-example-voting-app/vote
• The "results" load balanced web service: https://github.com/copilot-example-voting-app/results
• The "api" backend service: https://github.com/copilot-example-voting-app/api

How to run this application?

You can clone any of these repositories and run copilot init to start them.
I recommend starting out with the "api" microservice so that you initialize a database first.

How is the database defined?

The database is created as an Amazon Aurora Serverless PostgreSQL database defined here: https://github.com/copilot-example-voting-app/api/blob/main/copilot/api/addons/db.template.yaml

It leverages Copilot's Additional AWS resources feature.

How do the frontend services communicate with the "api" service?

Both frontend services "vote" and "results" use service discovery to communicate with the backend "api" service.
Here are some examples:

• https://github.com/copilot-example-voting-app/vote/blob/6e824d7b358c72466384d8a54a83d46c7f537e4a/server/server.go#L91-L92
• https://github.com/copilot-example-voting-app/results/blob/92ea65b850c94edcc279db3d5a0caa5241e87a0b/server/server.go#L65-L66