FastAPI requests to internal endpoint

I was working on a project recently and was experiencing problems with FastAPI interacting with the requests library. The goal I’m trying to achieve is to have a health_status endpoint function hit the health version endpoint as well. I have recreated the problem with 2 smaller projects, a simple fastapi and a simple flask. Flask is able to achieve the goal, but Fastapi freezes up when trying to do it.

Here is the code using flask. When hitting the “/health/status” endpoin it should return {“message”: “Hello World”} however it freezes up the entire api. It doesn’t even allow me to hit the root endpoint afterwards unless I rerun the program. However, I am able to hit the root endpoint if I hit it before calling “/health/status."

Code

import uvicorn
from fastapi import FastAPI, Request
import requests

app = FastAPI(debug=True)


@app.get("/")
async def root():
    return {"message": "Hello World"}


@app.get("/health/status")
async def health():
    resp = requests.get(url="http://127.0.0.1:8000/")
    return resp.text


if __name__ == "__main__":
    uvicorn.run(app, host="127.0.0.1", port=8000)

Similarly, the code using flask is listed below. This works just fine, where if I hit “/health/status” then it will return “Hello World”

from flask import Flask
import requests

app = Flask(__name__)


@app.route('/')
def hello_world():
    return 'Hello World'


@app.route('/health/status')
def health_status():
    resp = requests.get(url="http://127.0.0.1:5000/")
    return resp.text


if __name__ == '__main__':
    app.run()

Description

As mentioned above, instead of returning “Hello World” like it should, it just ties up the whole api when using FastAPI.

Environment

• OS: [e.g. Linux / Windows / macOS]: Windows
• FastAPI Version [e.g. 0.3.0]: “==0.63.0”
• Python version: “==3.6.8”