FastAPI Tutorial

fastapi_first_step.py

"""
FastAPIの基本的記法
- Python 3.9.7
- FastAPI 0.70.0
- uvicorn 0.15.0
"""
import uvicorn
from typing import Optional
from fastapi import FastAPI, Query, HTTPException
from pydantic import Field, BaseModel

app = FastAPI()


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


# path parameter
@app.get("/users/{name}")
async def get_user(name: str):
    return {"name": name}


# query parameter
@app.get("/users/id/{name}")
async def get_name_with_id(name: str, id: Optional[int] = None):
    return {"name": name, "id": id}


# query parameter and validation
@app.get("/v2/users/id/{name}")
async def get_name_with_id_validation(name: str, id: str = Query(..., regex="^[0-9]{2}$")):
    return {"name": name, "id": id}


class User(BaseModel):
    name: str
    age: Optional[int] = None


# post
@app.post("/users/")
async def post_user(user: User):
    return user


class UserWithMeta(BaseModel):
    name: str = Field(..., title="Name", description="Name of User")
    age: Optional[int] = Field(None, title="age", description="Age of User")


# post with meta data
@app.post("/v2/users/")
async def post_user_with_meta(user: UserWithMeta):
    return user


# response with response_model
@app.post("/v3/users/", response_model=User)
async def post_by_response_model(user: User):
    return user


# specify http status code
@app.get("/users/201/", status_code=201)
async def get_201():
    return {"Hello": "World"}


# raise 400 error
@app.get("/users/404/")
async def get_404():
    raise HTTPException(status_code=404, detail="User not found")


if __name__ == "__main__":
    uvicorn.run("main:app", host="0.0.0.0", port=8080, timeout_keep_alive=0, log_level="debug", reload=True)