Get方法抛出错误，不知道为什么

Question

我收到错误：TypeError: __init__() missing 1 required positional argument

整个错误是：

    [2021-09-04 22:00:53,162] ERROR in app: Exception on /entry/title [GET]
Traceback (most recent call last):

  File "/Users/shakur/PycharmProjects/flaskProject2/venv/lib/python3.9/site-packages/flask/app.py", line 1513, in full_dispatch_request
    rv = self.dispatch_request()

  File "/Users/shakur/PycharmProjects/flaskProject2/venv/lib/python3.9/site-packages/flask/app.py", line 1499, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)

  File "/Users/shakur/PycharmProjects/flaskProject2/venv/lib/python3.9/site-packages/flask_restful/__init__.py", line 467, in wrapper
    resp = resource(*args, **kwargs)

  File "/Users/shakur/PycharmProjects/flaskProject2/venv/lib/python3.9/site-packages/flask/views.py", line 82, in view
    self = view.view_class(*class_args, **class_kwargs)  # type: ignore

TypeError: __init__() missing 1 required positional argument: 'title'
127.0.0.1 - - [04/Sep/2021 22:00:53] "GET /entry/title HTTP/1.1" 500 -

由于某种原因，获取请求抛出错误，我不知道为什么......不知道。任何建议，将不胜感激

from flask import Flask
from flask_restful import Resource, Api
import sqlite3

app = Flask(__name__)
app.secret_key = "xyz"
api = Api(app)

class Entry(Resource):

    def __init__(self, title, language="Python", attempts=0,wins=0):
        self.title = title
        self.language = language
        self.attempts = attempts
        self.wins = wins


    def __repr__(self):
        #...


    def record_attempts_and_wins(self, a, w=0):
        #...

    @classmethod
    def find_entry_by_title(cls, title):
        connection = sqlite3.connect("data.db")
        cursor = connection.cursor()

        query = "SELECT * FROM entries WHERE title=?"
        result = cursor.execute(query, (title,))
        column = result.fetchone()
        if column:
            entry = cls(*column)
        else:
            entry = None

        connection.close()
        return entry


    def get(self, title):
        entry = Entry.find_entry_by_title(self, title)
        return entry

api.add_resource(Entry, "/entry/<string:title>")

Answer 1

Flask 不知道您已向Resource子类添加了位置参数。你打电话时：

api.add_resource(Entry, "/entry/<string:title>")

它只是认为Entrywill 是 a Resource，它的构造函数中没有参数title。title当它调用时，它怎么知道需要传递 aEntry()？

将构造函数参数传递到资源的文档中对此进行了解决。您需要告诉它什么作为标题传递：

api.add_resource(Entry, "/entry/<string:title>", resource_class_kwargs={ 'title': "some title" })