Dockerfile

# Multi-stage build for Spring Boot application
# Stage 1: Build the application
FROM maven:3.9-eclipse-temurin-17 AS build

WORKDIR /app

# Copy Maven wrapper and pom.xml first (for better layer caching)
COPY .mvn .mvn
COPY mvnw mvnw.cmd pom.xml ./

# Download dependencies (cached unless pom.xml changes)
RUN ./mvnw dependency:go-offline

# Copy source code
COPY src ./src

# Build the application (skip tests - run them in CI/CD pipeline)
RUN ./mvnw clean package -DskipTests

# Stage 2: Create the runtime image
FROM eclipse-temurin:17-jre-alpine

WORKDIR /app

# Create a non-root user for running the application
RUN addgroup -S spring && adduser -S spring -G spring

# Copy the built JAR from the build stage
COPY --from=build /app/target/*.jar app.jar

# Change ownership of the application files
RUN chown -R spring:spring /app

# Switch to non-root user
USER spring:spring

# Expose the application port
EXPOSE 8080

# Set JVM options for containerized environment
ENV JAVA_OPTS="-XX:+UseContainerSupport -XX:MaxRAMPercentage=75.0 -XX:+UseG1GC"

# Health check
HEALTHCHECK --interval=30s --timeout=3s --start-period=60s --retries=3 \
  CMD wget --no-verbose --tries=1 --spider http://localhost:8080/actuator/health || exit 1

# Run the application
ENTRYPOINT ["sh", "-c", "java $JAVA_OPTS -jar app.jar"]