Get security updates & parametrize base image name

And fix hadolint warning.

Signed-off-by: Eero Tamminen <[email protected]>

Dockerfile

@@ -4,19 +4,24 @@
 # Base image for GenAIComps based OPEA Python applications
 # Build: docker build -t opea/comps-base -f Dockerfile .
 
-FROM python:3.11-slim
+ARG IMAGE_NAME=python
+ARG IMAGE_TAG=3.11-slim
 
-RUN apt-get update
+FROM ${IMAGE_NAME}:${IMAGE_TAG} AS base
 
 ENV HOME=/home/user
 
 RUN useradd -m -s /bin/bash user && \
     mkdir -p $HOME && \
     chown -R user $HOME
 
+# get security updates
+RUN apt-get update && apt-get upgrade -y && \
+    apt-get clean && rm -rf /var/lib/apt/lists/*
+
 WORKDIR $HOME
 
-COPY *.toml *.py *.txt *.md LICENSE .
+COPY *.toml *.py *.txt *.md LICENSE ./
 
 RUN pip install --no-cache-dir --upgrade pip setuptools && \
     pip install --no-cache-dir -r requirements.txt