update backend Dockerfile to use GraalVM img

backend/Dockerfile

@@ -1,20 +1,34 @@
-FROM openjdk:17-jdk-alpine
-
-WORKDIR /backend-app
-
-# Copy the build.gradle, settings.gradle, and gradle.properties files first
-# This step helps leverage Docker's caching mechanism
-COPY build.gradle settings.gradle gradle.properties ./
-
-COPY gradlew ./
-COPY gradle ./gradle
-
-RUN ./gradlew dependencies --no-daemon
-
-COPY . .
-
-RUN ./gradlew build --no-daemon
-
-EXPOSE 8080
-
-CMD ["java", "-jar", "build/libs/wookieepedia-0.1-all.jar"]
+# Stage 1: Build the native executable using GraalVM
+FROM ghcr.io/graalvm/native-image:latest as build
+
+WORKDIR /backend-app
+
+# Copy the build.gradle, settings.gradle, and gradle.properties files first
+# This step helps leverage Docker's caching mechanism
+COPY build.gradle settings.gradle gradle.properties ./
+
+COPY gradlew ./
+COPY gradle ./gradle
+
+RUN ./gradlew dependencies --no-daemon
+
+COPY . .
+
+RUN ./gradlew build --no-daemon
+
+# Create the native image
+RUN native-image --no-fallback -H:Name=wookieepedia -cp build/libs/wookieepedia-0.1-all.jar
+
+# Stage 2: Create the final lightweight image
+FROM debian:buster-slim
+
+WORKDIR /backend-app
+
+# Copy the native executable from the build stage
+COPY --from=build /backend-app/wookieepedia /backend-app/wookieepedia
+
+# Expose the application port
+EXPOSE 8080
+
+# Set the entry point to the native executable
+ENTRYPOINT ["/backend-app/wookieepedia"]