FROM maven:3.9-eclipse-temurin-21-alpine AS builder

WORKDIR /build

COPY pom.xml .
RUN mvn dependency:go-offline -B -q

COPY src ./src
RUN mvn package -DskipTests -B -q

FROM eclipse-temurin:21-jre-alpine AS runtime

ENV TZ=Asia/Shanghai \
    JAVA_OPTS="-Xms256m -Xmx512m -XX:+UseG1GC"

WORKDIR /app

RUN addgroup -S app && adduser -S app -G app

COPY --from=builder /build/target/*.jar app.jar

EXPOSE 8081

USER app

CMD ["sh", "-c", "java $JAVA_OPTS -jar app.jar"]