Update Dockerfile

Author: shashankpandey2070

Dockerfile

@@ -1,13 +1,23 @@
-FROM node:18
+# ---------- Optimised Dockerfile ----------
+FROM node:18-slim
 
+ARG DEBIAN_FRONTEND=noninteractive
+
+# Install compilers & /usr/bin/time
 RUN apt-get update && \
-    apt-get install -y g++ openjdk-17-jdk python3 time
+    apt-get install -y --no-install-recommends \
+      g++ openjdk-17-jdk python3 python3-pip time && \
+    rm -rf /var/lib/apt/lists/*
 
 WORKDIR /app
+
+COPY package*.json ./
+RUN npm ci --omit=dev       # reproducible, no devDependencies
+
 COPY . .
-RUN npm install
 
 ENV JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64
 ENV PATH=$JAVA_HOME/bin:$PATH
 
+EXPOSE 8080                 # purely informational
 CMD ["node", "server.js"]