README.md

Distribute coin API

When user receives an Verifiable Credential(VC) from IDP, user can submit the VC to the Redbelly Network to gain write permission to the network. However, when user submit this initial request, user MUST have RBNT to submit the transaction. Therefore, this service, allows IDP to distribute the initial RBNT to user

This service has /distribute?address=0x70997970C51812dc3A010C7d01b50e0d17dc79C8 to distribute 1 RBNT to the given address

The team has developed this solution, when this API is called in lower rate, everything work perfectly However, when it in high load, example 100 requests per seconds, the application start to fail.

Test Loader

Initially, the team has the following loader seq/main.go with the following code

func main() {
	for i := 0; i < 100; i++ {
		resp, err := http.Get("http://localhost:8080/distribute?address=0x70997970C51812dc3A010C7d01b50e0d17dc79C8")
		if err != nil {
			log.Fatalln(err)
		}
		log.Printf("response %v", resp)
	}
}

This work perfectly with no error

However, the read world situation is concurrent request parallel/main.go

func main() {
	var wg sync.WaitGroup
	for i := 0; i < 100; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()
			resp, err := http.Get("http://localhost:8080/distribute?address=0x70997970C51812dc3A010C7d01b50e0d17dc79C8")
			if err != nil {
				log.Fatalln(err)
			}
			log.Printf("response %v", resp)
		}()
	}
	wg.Wait()
}

Your tasks

• Improve the API can handle 100 requests per seconds without fail
• The service MUST be able to deliver the coin

Assumption and Precondition

• No database, can use internal map or any storage for demo purpose

How to Test

1. Start a local blockchain using hardhat
2. Start the service
3. Make a lot of requests

Each step run in it own console window

1. Start local blockchain

cd node
npm install
npx hardhat node

2. Start the service

go run main.go

3. Start the loader

go run parallel/main.go