Dockerfile

# Multi-stage Dockerfile for User Data Aggregator Service
# Build stage
FROM eclipse-temurin:21-jdk-alpine AS builder

WORKDIR /app

# Copy Maven wrapper and pom.xml first for better caching
COPY mvnw .
COPY .mvn .mvn
COPY pom.xml .

# Make mvnw executable
RUN chmod +x mvnw

# Download dependencies (cached layer)
RUN ./mvnw dependency:go-offline -B

# Copy source code
COPY src src

# Build the application (skip tests - they should run in CI)
RUN ./mvnw clean package -DskipTests -B

# Extract layers for better Docker caching
RUN java -Djarmode=layertools -jar target/*.jar extract --destination target/extracted

# Runtime stage
FROM eclipse-temurin:21-jre-alpine AS runtime

# Create non-root user for security
RUN addgroup -g 1001 -S appgroup && \
    adduser -u 1001 -S appuser -G appgroup

WORKDIR /app

# Copy extracted layers
COPY --from=builder /app/target/extracted/dependencies/ ./
COPY --from=builder /app/target/extracted/spring-boot-loader/ ./
COPY --from=builder /app/target/extracted/snapshot-dependencies/ ./
COPY --from=builder /app/target/extracted/application/ ./

# Set ownership
RUN chown -R appuser:appgroup /app

# Switch to non-root user
USER appuser

# Expose port
EXPOSE 8080

# Health check
HEALTHCHECK --interval=30s --timeout=10s --start-period=60s --retries=3 \
    CMD wget --no-verbose --tries=1 --spider http://localhost:8080/actuator/health || exit 1

# JVM options for containers
ENV JAVA_OPTS="-XX:+UseContainerSupport \
    -XX:MaxRAMPercentage=75.0 \
    -XX:InitialRAMPercentage=50.0 \
    -XX:+UseG1GC \
    -XX:+UseStringDeduplication \
    -Djava.security.egd=file:/dev/./urandom"

# Run the application
ENTRYPOINT ["sh", "-c", "java $JAVA_OPTS org.springframework.boot.loader.launch.JarLauncher"]