use multi-stage builds in dockerfile

Dockerfile

@@ -1,27 +1,40 @@
-# Based on https://dev.to/farcellier/package-a-poetry-project-in-a-docker-container-for-production-3b4m
-# and https://stackoverflow.com/questions/53835198/integrating-python-poetry-with-docker
+# Dockerfile that builds the Rogue Scholar API Docker image.
+# Based on https://medium.com/@albertazzir/blazing-fast-python-docker-builds-with-poetry-a78a66f5aed0
 ARG BUILDPLATFORM=linux/amd64
-FROM --platform=$BUILDPLATFORM python:3.12-slim-bookworm AS base
+FROM --platform=$BUILDPLATFORM python:3.12-bookworm as builder
 
 ENV PANDOC_VERSION=3.1.12.3
 ENV POETRY_VERSION=1.8.2
 
 # Update installed APT packages
 RUN apt-get update && apt-get upgrade -y && \
-    apt-get install wget nano tmux tzdata weasyprint -y && \
+    apt-get install wget weasyprint -y && \
     wget -q https://github.com/jgm/pandoc/releases/download/${PANDOC_VERSION}/pandoc-${PANDOC_VERSION}-1-amd64.deb && \
     dpkg -i pandoc-${PANDOC_VERSION}-1-amd64.deb && \
     apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
-RUN pip install --no-cache-dir poetry==${POETRY_VERSION} 
+RUN pip install poetry==${POETRY_VERSION} 
 
-# WORKDIR /app
+ENV POETRY_NO_INTERACTION=1 \
+    POETRY_VIRTUALENVS_IN_PROJECT=1 \
+    POETRY_VIRTUALENVS_CREATE=1 \
+    POETRY_CACHE_DIR=/tmp/poetry_cache
 
-ENV PATH .venv/bin:$PATH
+WORKDIR /app
 
-COPY . /.
-RUN poetry install --without dev
+COPY pyproject.toml poetry.lock ./
+RUN touch README.md
+RUN --mount=type=cache,target=$POETRY_CACHE_DIR poetry install --without dev --no-root
 
+
+FROM python:3.12-slim-bookworm as runtime
+
+ENV VIRTUAL_ENV=/app/.venv \
+    PATH="/app/.venv/bin:$PATH"
+
+COPY --from=builder ${VIRTUAL_ENV} ${VIRTUAL_ENV}
+
+COPY api ./api
 EXPOSE 8080
 
-CMD ["poetry", "run", "hypercorn", "-b",  "0.0.0.0:8080", "api:app"]
+CMD ["hypercorn", "-b",  "0.0.0.0:8080", "api:app"]