Reduce size of docker image by adding building stage

Author: maexled

Dockerfile

@@ -1,17 +1,29 @@
-FROM python:3.12-alpine
+# Stage 1: Build stage
+FROM python:3.12-alpine AS builder
 
 WORKDIR /app
 
-COPY requirements.txt ./
-
-
-RUN apk add gcc musl-dev mariadb-connector-c-dev libpq-dev
+COPY requirements.txt .
 
+RUN apk add --no-cache --virtual .build-deps gcc musl-dev mariadb-connector-c-dev libpq-dev
 
 RUN pip install --no-cache-dir --upgrade pip && \
     pip install --no-cache-dir gunicorn && \
     pip install --no-cache-dir -r requirements.txt
 
+# Stage 2: Final stage
+FROM python:3.12-alpine
+
+WORKDIR /app
+
+COPY --from=builder /usr/local/lib/python3.12/site-packages /usr/local/lib/python3.12/site-packages
+COPY --from=builder /usr/local/bin/gunicorn /usr/local/bin/gunicorn
+COPY --from=builder /app /app
+
+RUN apk add --no-cache mariadb-connector-c libpq
+
 COPY . .
-CMD python manage.py makemigrations && python manage.py migrate && python manage.py collectstatic --noinput && gunicorn --bind=0.0.0.0:8000 --timeout 300 --workers=3 --threads=3 --max-requests 5 --max-requests-jitter 2 pim.wsgi:application
-EXPOSE 8000/tcp
+
+CMD ["sh", "-c", "python manage.py makemigrations && python manage.py migrate && python manage.py collectstatic --noinput && gunicorn --bind=0.0.0.0:8000 --timeout 300 --workers=3 --threads=3 --max-requests 5 --max-requests-jitter 2 pim.wsgi:application"]
+
+EXPOSE 8000/tcp