FastAPI 服务器返回“422 无法处理的实体”- value_error.missing

from http.client import responses
from random import randrange
from tkinter.tix import STATUS
from typing import Optional
from urllib import response
from fastapi import Body, FastAPI, Response ,status, HTTPException
from pydantic import BaseModel

app= FastAPI()

class Post(BaseModel):
    title: str
    content: str
    Published: bool = True
    rating: Optional[int] = None

my_post = [{"title": "title of post 1", "content": "content of post 1", "id": 2},{"title": "title of post 2","content":"content of post 2", "id":3}]

def find_post(id):
    for p in my_post:
        if p["id"] == id:
         return p

def find_index_post(id):
    for i,p in enumerate(my_post):
        if p["id"]== id:

            return i 



@app.get("/posts/{id}")
def get_posts(id: int , response: Response):
    post= find_post(id)
    if not post :

        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail= f"post with id {id} not found bludd")


        # response.status_code=status.HTTP_404_NOT_FOUND
        # return {"message": f" post with id : {id} not found"}

    return{"here is the post": post}  

@app.delete("/posts/{id}", status_code= status.HTTP_204_NO_CONTENT)
def delete_post(id: int):
    index= find_index_post(id)
    if index == None:
        raise HTTPException(status_code= status.HTTP_404_NOT_FOUND, detail= f"post with id {id} does not exist")
    my_post.pop(index)
    
    return Response(status_code= status.HTTP_204_NO_CONTENT)

@app.put("/posts/{id}")
def update_post(id: int , post: Post):
    index = find_index_post(id)
    if index == None :
        raise HTTPException(status_code= status.HTTP_404_NOT_FOUND, detail= f"post with id {id} does not exist")
    post_dict = my_post.dict()
    post_dict["id"]= id
    my_post[index]= post_dict
    return {"message" : "updated post"}

   

其他一切都有效，但put/update函数在最后。 从字面上看，随着教程进行编码，并且有不间断的恼人问题。

Python 控制台说： 422 Unprocessable Entity.

邮递员说：

"detail": 
"loc":
"body","msg": "field required",
"type": "value_error.missing"

The 422 unprocessable entity错误准确地告诉您请求的哪一部分与预期格式不匹配或丢失。就你而言，它说body不见了。当使用 Pydantic 模型时，你本质上声明了一个JSON对象（或 Python 字典），因此，您的端点需要一个请求正文JSON 格式。因此，您发送的请求必须包含JSON与 Pydantic 模型匹配的有效负载。下面是一个使用Python请求的例子（更多细节可以在这个答案），但您也可以使用 OpenAPI/Swagger UI 自动文档http://127.0.0.1:8000/docs测试 API。另外，请看一下这个答案有关更多详细信息和示例422 unprocessable entity发布 JSON 数据时出错。

Example

app.py

from pydantic import BaseModel

class Post(BaseModel):
    title: str
    content: str
    published: bool = True
    rating: Optional[int] = None

# ...

@app.put('/posts/{id}')
def update_post(id: int , post: Post):
    pass

test.py

import requests

post_id = 2
url = f'http://127.0.0.1:8000/posts/{post_id}'
payload = {"title": "string", "content": "string", "published": True, "rating": 0}
resp = requests.put(url, json=payload)
print(resp.json())