Winter Is Coming - The game

Protect the Wall

The game

Check the rules at: https://github.com/mysteriumnetwork/winter-is-coming/blob/master/quests/Talk_to_Zombies.md

Background

I've chosen to implement an agnostic game engine that can be executed from different context, to comply with the exercise it is executed trough command line server/client architecture, but it could be plugged to a web server or behind a gRPC proxy server for example

Libraries

I've deliberately avoided using libraries to maximize the chances of having to deal with Go most iconic types, structures and built-in packages; in a real world scenario I would spend some time to find what is best suited for the task at hands.

Code style

Although there's inherent style in my code (like use NewX for constructors or non exported errors), I'm still flexible and as long as the team agrees on a standard I'm happy to follow it

How to install

Clone the repo into GOPATH

mkdir -p $GOPATH/src/github.com/hmoragrega
cd $GOPATH/src/github.com/hmoragrega
git clone git@github.com:hmoragrega/winterfell.git
cd winterfell

How to test

Install the dependencies

The tests require a library to ease doing asserts and mocks
Either get it globally or use the provide dependencies to install it as a local vendor

go get github.com/stretchr/testify/assert
go get github.com/golang/mock/gomock

Using dep package manager

dep ensure

Run the tests

make tests

If GNU make file is not installed you can use:

go test -timeout 5s ./cmd/server ./game

See code coverage

make coverage

If GNU make file is not installed you can use:

make tests-ci TEST_FLAGS=-coverprofile=coverage.out
go tool cover -html=coverage.out

How to build

Disclaimer: The version of Go used to develop this app is >= go1.10
If you have installed GNU make you can invoke a helper command that will build it for you

make build

Alternatively run the native command to build the server and the client

go build -o bin/cmd-server cmd/server/server.go cmd/server/commands.go
go build -o bin/cmd-client cmd/client/client.go

How to run

Start the server in a terminal and the client in another, once finished playing you can kill them with Ctrl-c

You can pass an optional flag address in case the default port is in use

$ bin/cmd-server -address=:8122
Listening on address :8122

$ bin/cmd-client -address=127.0.0.1:8122
Connected to game server

Build the server as docker image

Given you have docker and make installed in your machine you can also use it to build images for both the server and the client without requiring neither Go or dep installed

make docker-build

Then to start it

make docker-server

NOTE: Since no configuration is passed to the app it will read try to use the default port always

Things I would improve

I've tried to stay true to the workday limit, I would love to implement some of the bonus points for the test, and also there's some other general things that I would improve:

Parameterize the server and game options (port, board size, etc) with:
- command line flags
- environmental variables
- config files
Add the the bonus points features
Manage future dependencies with a package manager: dep, glide
Improve logging
- Use level thresholds and hide debug messages
- Add context to debug problems (client, address)
Handle OS signals
Improve code coverage
Use some library to ease the handling of the server/client communication
Use a release tool to create cross-platform binaries and native packages, I've used goreleaser in the past in CI/CD pipelines with great results
Add monitoring metrics