問題:
對方是要的訊息Hello World，不是要”Hello World”

原本的FastAPI寫法如下:

from fastapi import FastAPI
import uvicorn

app = FastAPI()


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

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

可以看到最常見的postman發的請求得到是”Hello World”

解決方式:
使用:PlainTextResponse

from fastapi import FastAPI
import uvicorn
from fastapi.responses import PlainTextResponse

app = FastAPI()


@app.get("/", response_class=PlainTextResponse)
async def root():
    return "Hello World"

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

可以看到還滿順利的出現了單純只有文字的Hello World

不一定要放在response_class，以下方式也能成功:

from fastapi import FastAPI
import uvicorn
from fastapi.responses import PlainTextResponse

app = FastAPI()

def get_text(parameters):
    text = PlainTextResponse(parameters)
    return text


@app.get("/")
async def root():
    op = get_text('hello bocky')
    return op

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