프로파일 관리: application.yml

src/main/resources/
├── application.yml          # 공통
├── application-dev.yml      # 개발
├── application-staging.yml  # 스테이징
├── application-prod.yml     # 프로덕션

spring:
  application:
    name: ohs-backend
  profiles:
    active: ${SPRING_PROFILES_ACTIVE:dev}

server:
  port: 8080
  shutdown: graceful

management:
  endpoints:
    web:
      exposure:
        include: health,info,metrics

spring:
  datasource:
    url: jdbc:h2:mem:devdb
    driver-class-name: org.h2.Driver
  jpa:
    hibernate:
      ddl-auto: create-drop
    show-sql: true

logging:
  level:
    root: DEBUG
    org.springframework.web: DEBUG

spring:
  datasource:
    url: ${DB_URL}
    username: ${DB_USERNAME}
    password: ${DB_PASSWORD}
    hikari:
      maximum-pool-size: 20
      connection-timeout: 30000
  jpa:
    hibernate:
      ddl-auto: validate  # 절대 자동 생성 금지
    show-sql: false

logging:
  level:
    root: INFO
  file:
    name: /var/log/app.log

server:
  forward-headers-strategy: native  # AWS ALB 뒤

@ConfigurationProperties(prefix = "app")
@Validated
public record AppProperties(
    @NotBlank String name,
    @NotBlank String version,
    AwsConfig aws,
    JwtConfig jwt
) {
    public record AwsConfig(
        @NotBlank String region,
        @NotBlank String s3Bucket
    ) {}

    public record JwtConfig(
        @NotBlank String secret,
        @Min(60) long expireMinutes
    ) {}
}


@Configuration
@EnableConfigurationProperties(AppProperties.class)
public class AppConfig { }


// 사용
@Service
@RequiredArgsConstructor
public class S3Service {
    private final AppProperties properties;

    public String getBucket() {
        return properties.aws().s3Bucket();
    }
}

# application.yml
app:
  name: OHS Backend
  version: 1.0.0
  aws:
    region: ap-northeast-2
    s3-bucket: ${S3_BUCKET}
  jwt:
    secret: ${JWT_SECRET}
    expire-minutes: 30

방법 1 — 환경변수 (단순)
export DB_PASSWORD=secret

방법 2 — .env 파일 (개발)
DB_PASSWORD=secret
# .gitignore에 추가

방법 3 — AWS Secrets Manager / Parameter Store
spring.config.import: aws-secretsmanager:my-app-secrets/
spring.cloud.aws.secretsmanager.region: ap-northeast-2

방법 4 — HashiCorp Vault
spring.config.import: vault://
spring.cloud.vault.host: vault.example.com
spring.cloud.vault.token: ${VAULT_TOKEN}

방법 5 — Kubernetes Secrets
envFrom:
  - secretRef:
      name: app-secrets

@SpringBootTest
@ActiveProfiles("test")
class UserServiceTest {
    // application-test.yml 적용
}