add linter and make file (#2)

Makefile

@@ -0,0 +1,60 @@
+# project variables
+PROJECT_NAME := mullvad-best-server
+
+# build variables
+.DEFAULT_GOAL = lint
+BUILD_DIR := dist
+DEV_GOARCH := $(shell go env GOARCH)
+DEV_GOOS := $(shell go env GOOS)
+
+
+## tools: Install required tooling.
+.PHONY: tools
+tools:
+ifeq (,$(wildcard ./.bin/golangci-lint*))
+	@curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b .bin/ v1.44.2
+else
+	@echo "==> Required tooling is already installed"
+endif
+
+## clean: Delete the build directory
+.PHONY: clean
+clean:
+	@echo "==> Removing '$(BUILD_DIR)' directory..."
+	@rm -rf $(BUILD_DIR)
+
+## lint: Lint code with golangci-lint.
+.PHONY: lint
+lint: tools
+	@echo "==> Linting code with 'golangci-lint'..."
+	@.bin/golangci-lint run ./...
+
+## test: Run all unit tests.
+.PHONY: test
+test:
+	@echo "==> Running unit tests..."
+	@mkdir -p $(BUILD_DIR)
+	@go test -count=1 -v -cover -coverprofile=$(BUILD_DIR)/coverage.out -parallel=4 ./...
+
+## build: Build binary for default local system's OS and architecture.
+.PHONY: build
+build:
+	@echo "==> Building binary..."
+	@echo "    running go build for GOOS=$(DEV_GOOS) GOARCH=$(DEV_GOARCH)"
+# workaround for missing .exe extension on Windows
+ifeq ($(OS),Windows_NT)
+	@go build -o $(BUILD_DIR)/$(PROJECT_NAME).$(DEV_GOOS).$(DEV_GOARCH).exe
+else
+	@go build -o $(BUILD_DIR)/$(PROJECT_NAME).$(DEV_GOOS).$(DEV_GOARCH)
+endif
+
+.PHONY: run
+run:
+	@echo "==> Running $(PROJECT_NAME)"
+	@go run main.go
+
+help: Makefile
+	@echo "Usage: make <command>"
+	@echo ""
+	@echo "Commands:"
+	@sed -n 's/^##//p' $< | column -t -s ':' | sed -e 's/^/ /'