我从Flask的Blueprints应用程序中获得404错误。这是在Windows 10上运行最新的PyCharm和python 3.11。
我已经看到了几个，通常是多年前，这个问题的版本。我有一个Flask应用程序，它并不完整，但在早期开发中“工作”。我被安排了一系列其他项目，现在又回到了Flask应用程序上。我更新了Python、Flask及其依赖项。
当我在PyCharm调试器中启动应用程序时，它会运行并显示预期的启动信息：

FLASK_APP = my_app/my_app.py
FLASK_ENV = development
FLASK_DEBUG = 0
In folder C:/Users/ME/PycharmProjects/Project_folder
import sys; print('Python %s on %s' % (sys.version, sys.platform))
C:\Users\ME\PycharmProjects\Project_folder\venv\Scripts\python.exe C:/JetBrains/PyCharm-2023.2.1/plugins/python/helpers/pydev/pydevd.py --module --multiprocess --qt-support=auto --client 127.0.0.1 --port 50785 --file flask run 
Connected to pydev debugger (build 232.9559.58)
[2023-09-29 14:31:12,134] INFO in my_app: STARTING APP
 * Serving Flask app 'my_app/my_app.py'
 * Debug mode: on
WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.
 * Running on http://127.0.0.1:5000
Press CTRL+C to quit

我的项目布局--为了简洁而编辑

:.
|   my_app.py
|   CONFIG.ini
|   requirements.txt
+---app
|   |   local_settings.py
|   |   settings.py
|   |   __init__.py
|   +---models
|   +---static  
|   +---templates
|   +---views
|   |   |   admin.py
|   |   |   API.py
|   |   |   main.py
|   |   |   utilities.py
|   |   |   __init__.py

我在以下方面定义蓝图：admin.py、API.py和main.py。admin和API部分目前只是存根。
my_app.py看起来像：

from app import create_app
my_app = None
try:
    my_app = create_app()
    my_app.logger.info(f'STARTING APP')
except Exception as e:
    msg = repr(e)
    if my_app:
        my_app.logger.error(f'{repr(msg)}')
    print(repr(msg))

aoo/__init__.py看起来像这样。注意create_app()中的register_blueprints(app)调用;下面是app/utilities.py。它正在注册蓝图，因为我可以在函数调用之后放置一个断点，并在app对象中沿着规则。

import os
from dotenv import load_dotenv
from flask import Flask
from flask_mail import Mail
from flask_migrate import Migrate
from flask_sqlalchemy import SQLAlchemy
from flask_user import UserManager
from flask_wtf.csrf import CSRFProtect
from app.models.user import User, UserRegisterForm, UserProfileForm, UserLoginForm
from app.views.utilities import register_api, register_blueprints
# Instantiate Flask
app = Flask(__name__)
csrf_protect = CSRFProtect()
mail = Mail()
db = SQLAlchemy()
migrate = Migrate()
user_manager = None
def create_app():
    try:
        load_dotenv()
        app.config.from_object("app.settings")
        app.config.from_object("app.local_settings")
        # Set up an error-logger to send emails to app.config.ADMINS
        init_file_error_handler(app)
        init_email_error_handler(app)
        csrf_protect.init_app(app)
        mail.init_app(app)
        db.init_app(app)
        migrate.init_app(app, db)
        # Setup Flask-User
        global user_manager
        user_manager = UserManager(app, db, User)
        user_manager.RegisterFormClass = UserRegisterForm
        user_manager.EditUserProfileFormClass = UserProfileForm
        user_manager.LoginFormClass = UserLoginForm
        register_blueprints(app)
        return app
    except Exception as e:
        print(repr(e))
        raise e
@app.context_processor
def context_processor():
    return dict(user_manager=user_manager)
def init_file_error_handler(my_app):
    ...
def init_email_error_handler(my_app):
    ...

utilities.py：

from app.views.API import API_blueprint
from app.views.admin import admin_blueprint
from app.views.main import main_blueprint
def register_blueprints(my_app):
    try:
        my_app.register_blueprint(main_blueprint)
        my_app.register_blueprint(admin_blueprint)
        my_app.register_blueprint(API_blueprint)
    except Exception as e:
        raise
def register_api(my_app, view, endpoint, url, pk="id", pk_type="uuid"):
    ...

main.py有基本的主页和其他东西：

import os
import random
from datetime import timedelta
from flask import redirect, render_template, session
from flask import request, url_for, Blueprint
from flask_user import current_user, login_required
main_blueprint = Blueprint("main", __name__, template_folder="templates")
# The Home page is accessible to anyone
@main_blueprint.route("/")
def home_page():
    from app import app
    ...
    return render_template("main/home_page.html")

PyCharm调试器启动;我可以在my_app.py中中断create_app()调用;跳过创建步骤并检查my_app对象，据我所知，它似乎被正确填充，而不是这方面的Maven。
点击PyCharm调试窗口中的URL会弹出一个浏览器，但会报告404错误。据我所知，没有其他错误被抛出。
有什么想法？

次要编辑FLASK_DEBUG应设置为0以上。
更新我刚刚了解了flask routes命令。在调试器中，我可以看到蓝图已经添加，但当我运行routs命令时，我几乎什么也没有得到：

> flask --app .\my_app\app routes
Endpoint  Methods  Rule                   
--------  -------  -----------------------
static    GET      /static/<path:filename>