[CI/CD] dockerhub에 image를 push하는 CI #1

	name: Java CI with Gradle

	on:
	push:
	branches: [ "main" ]
	pull_request:
	branches: [ "main" ]

	jobs:
	build:
	# Workflow가 실행되는 vm의 OS 지정
	runs-on: ubuntu-latest
	permissions:
	contents: read

	steps:
	# Repository 코드를 Workflow 환경으로 가져오기
	- uses: actions/checkout@v4

	# Java 17 설정
	- name: Set up JDK 17
	uses: actions/setup-java@v4
	with:
	java-version: '17'
	distribution: 'temurin'

	# yml 파일의 환경변수 설정
	- name: Set yml file
	uses: microsoft/variable-substitution@v1
	with:
	files: ./src/main/resources/application.yml
	env:
	spring.datasource.url: ${{ secrets.DB_MYSQL_URL }}
	spring.datasource.username: ${{ secrets.DB_MYSQL_USERNAME }}
	spring.datasource.password: ${{ secrets.DB_MYSQL_PASSWORD }}

	# 실행 속도 향상을 위한 Gradle 종속성 캐싱
	- name: Setup Gradle
	uses: gradle/actions/setup-gradle@af1da67850ed9a4cedd57bfd976089dd991e2582 # v4.0.0

	# gradlew 파일에 실행 권한 부여
	- name: Grant execute permission for gradlew
	run: chmod +x gradlew

	# Spring Boot 애플리케이션 빌드
	- name: Build with Gradle Wrapper
	run: ./gradlew build

	# Docker 이미지 빌드
	- name: docker image build
	run: docker build -t ${{ secrets.DOCKERHUB_USERNAME }}/mercury-server .

	# DockerHub 로그인
	- name: docker login
	uses: docker/login-action@v2
	with:
	username: ${{ secrets.DOCKERHUB_USERNAME }}
	password: ${{ secrets.DOCKERHUB_PASSWORD }}

	# DockerHub 이미지 푸시
	- name: docker Hub push
	run: docker push ${{ secrets.DOCKERHUB_USERNAME }}/mercury-server

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