I’m building a few FastAPI apps to throw in docker and run on my homelab… I wanted to add healthchecks and here’s a simple way to do it
Make sure to install curl in the dockerfile (near the top for effeciency)
# Install curl with minimal dependencies
RUN apt-get update && \
apt-get install -y --no-install-recommends curl && \
apt-get clean && \
rm -rf /var/lib/apt/lists/*
Then I recommend making compose files even for single image deployments
services:
app:
build: .
volumes:
- type: bind
source: .
target: /app
environment:
- PYTHONPATH=/app
- DOCKER_ENV=true
- UV_VIRTUALENV=/opt/app-env
user: "1000:1000"
restart: unless-stopped
healthcheck:
test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
interval: 30s
timeout: 10s
retries: 3
start_period: 10s
Then finally you’ll need a /health endpoint
@app.get("/health", response_class=HTMLResponse)
async def health_check():
"""
A health check endpoint that returns a status message.
"""
return "<html><body><h1>Service is healthy</h1></body></html>"
