Added Makefile, Dockerfile and other CI improvements #5

	name: Release prom-exporter

	on:
	push:
	branches-ignore:
	- '**'
	tags:
	- 'v..*'

	permissions:
	contents: write

	jobs:
	release:
	runs-on: ubuntu-latest

	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Set up Go
	uses: actions/setup-go@master
	with:
	go-version: 1.21.x

	- name: Set up Docker Buildx
	uses: docker/setup-buildx-action@v3

	- name: Login to Docker Hub
	if: ${{ !env.ACT }}
	uses: docker/login-action@v3
	with:
	username: ${{ secrets.DOCKERHUB_USERNAME }}
	password: ${{ secrets.DOCKERHUB_TOKEN }}

	- name: Prepare
	id: prepare
	if: ${{ !env.ACT }}
	run: echo "tag_name=${GITHUB_REF#refs/tags/}" >> $GITHUB_OUTPUT

	- name: Build image
	id: build
	if: ${{ env.ACT }}
	uses: docker/build-push-action@v5
	with:
	context: .
	load: true
	tags: prom-exporter:test

	- name: Test Execution
	if: ${{ env.ACT }}
	run: \|
	timeout 10s docker run --rm prom-exporter:test \
	-listen-address ":9201" \
	-service-name "test" -service-uri "test" -service-port "5066" -service-metrics-path "stats" \|\| code=$?
	if [[ $code -ne 124 ]]; then
	echo "Exporter stopped with ${code}. It was expected to run forever."
	exit 1;
	fi

	- name: Release
	if: ${{ !env.ACT }}
	uses: goreleaser/goreleaser-action@v5
	with:
	version: latest
	args: release --clean --timeout=5m
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	VERSION: ${{ steps.prepare.outputs.tag_name }}

	- name: Build and push
	if: ${{ !env.ACT }}
	uses: docker/build-push-action@v5
	with:
	context: .
	file: Dockerfile.release
	push: true
	tags: mgsousa/prom-exporter:latest,mgsousa/prom-exporter:${{ steps.prepare.outputs.tag_name }}

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