Stacking Routes

Let's consider a very basic FastAPI app that has a health endpoint.

from fastapi import FastAPI

app = FastAPI()

@app.get("/health")
def get_health():
    return {"status": "alive"}

This /health endpoint has one job: to return a response with status 200. It can serve as a signal that the service is healthy and this is typically used by cloud providers as a indication that a service might need a restart.

Some services however, don't use /health but /healthz instead. So how might you implement this? You could add another route.

from fastapi import FastAPI

app = FastAPI()

@app.get("/health")
def get_health():
    return {"status": "alive"}

@app.get("/healthz")
def get_health():
    return {"status": "alive"}

But there's a simpler way, you can also just do this:

from fastapi import FastAPI

app = FastAPI()

@app.get("/health")
@app.get("/healthz")
def get_health():
    return {"status": "alive"}

You can totally stack decorators in Python, and FastAPI will just consider it another route that needs to be added.

So you only need a single line of code. Neat!