fizz-buzz-gin

The game rules

The original fizz-buzz consists in writing all numbers from 1 to 100, and replacing:

• all multiples of 3 by fizz,
• all multiples of 5 by buzz,
• and all multiples of 15 by fizzbuzz.

The output would look like this:

1,2,fizz,4,buzz,fizz,7,8,fizz,buzz,11,fizz,13,14,fizzbuzz,fizz,...

Problem

Expose a REST API endpoint /fizz-buzz that accepts five parameters : two strings (say, string1 and string2), and three integers (say, int1, int2 and limit), and returns a JSON It must return a list of strings with numbers from 1 to limit, where:

• all multiples of int1 are replaced by string1,
• all multiples of int2 are replaced by string2,
• all multiples of int1 and int2 are replaced by string1string2

Expose a REST API endpoint /stats that retrieves all statistics about the calls

Solution

I have used gin-gonic framework to handle the web server part, and build/test my endpoints. This part is located in the pkg/server folder.

The core of the game rules are located in the pkg/business folder.

The statistics storage is a SQlite database and the service client is located in pkg/storage folder.

Getting started

For both following cases, you can test the endpoint:

• either in the browser
• either in swagger

Launch locally

The project has been set up on Windows, following commands might change on other OS

Launch all tests and check coverage:

go test -race -covermode atomic -coverprofile .\coverage.txt ./...

Build:

go build -o fizzBuzzApp .\cmd\api\main.go

Run:

go run .\cmd\api\main.go

Using Docker Compose

Requirements

Install Docker Engine

The image is build in the Gitlab CI according to the .gitlab-ci.yml file and the Dockerfile. It it then pushed to the registry. The docker-compose.yaml file pulls it from the registry and runs a container within Docker Engine.

• To update the image:

docker-compose pull

• To run the image

docker-compose up -d