reflex_copy/docker-example/production-one-port/Dockerfile

# This Dockerfile is used to deploy a single-container Reflex app instance
# to services like Render, Railway, Heroku, GCP, and others.

# If the service expects a different port, provide it here (f.e Render expects port 10000)
ARG PORT=8080
# Only set for local/direct access. When TLS is used, the API_URL is assumed to be the same as the frontend.
ARG API_URL

# It uses a reverse proxy to serve the frontend statically and proxy to backend
# from a single exposed port, expecting TLS termination to be handled at the
# edge by the given platform.
FROM python:3.13 as builder

RUN mkdir -p /app/.web
RUN python -m venv /app/.venv
ENV PATH="/app/.venv/bin:$PATH"

WORKDIR /app

# Install python app requirements and reflex in the container
COPY requirements.txt .
RUN pip install -r requirements.txt

# Install reflex helper utilities like bun/node
COPY rxconfig.py ./
RUN reflex init

# Install pre-cached frontend dependencies (if exist)
COPY *.web/bun.lockb *.web/package.json .web/
RUN if [ -f .web/bun.lockb ]; then cd .web && ~/.local/share/reflex/bun/bin/bun install --frozen-lockfile; fi

# Copy local context to `/app` inside container (see .dockerignore)
COPY . .

ARG PORT API_URL
# Download other npm dependencies and compile frontend
RUN API_URL=${API_URL:-http://localhost:$PORT} reflex export --loglevel debug --frontend-only --no-zip && mv .web/_static/* /srv/ && rm -rf .web


# Final image with only necessary files
FROM python:3.13-slim

# Install Caddy and redis server inside image
RUN apt-get update -y && apt-get install -y caddy redis-server && rm -rf /var/lib/apt/lists/*

ARG PORT API_URL
ENV PATH="/app/.venv/bin:$PATH" PORT=$PORT API_URL=${API_URL:-http://localhost:$PORT} REDIS_URL=redis://localhost PYTHONUNBUFFERED=1

WORKDIR /app
COPY --from=builder /app /app
COPY --from=builder /srv /srv

# Needed until Reflex properly passes SIGTERM on backend.
STOPSIGNAL SIGKILL

EXPOSE $PORT

# Apply migrations before starting the backend.
CMD [ -d alembic ] && reflex db migrate; \
    caddy start && \
    redis-server --daemonize yes && \
    exec reflex run --env prod --backend-only