Flask路由注册异常问题排查求助

我现在正在开发一个Flask Web应用，遇到了一些意料之外的问题。

我的项目结构大致如下：

1. app/__init__.py

def create_app(test_config=None):
 .. some other stuff ...
from app.views import auth
app.register_blueprint(auth)

return app

2. app\views\__init__.py

from flask import Blueprint

auth = Blueprint('auth', __name__, url_prefix='/auth')

from .auth_views import auth as auth_bp

def register_blueprints(app):
    app.register_blueprint(auth_bp)

3. app\views\auth_views.py

from flask import Blueprint
from app.controllers import auth_controller

auth = Blueprint('auth', __name__)  

#register route
@auth.route('/register', methods=['GET', 'POST'])
def register():
    return auth_controller.register()

..... some other routes .... 

4. app\controllers\auth_controller.py

from flask import render_template, request, redirect, url_for, flash, abort, Blueprint
from flask_login import login_user, logout_user, current_user
from app import db, bcrypt
from app.models import User,Role
from app.forms.auth_forms import RegistrationForm, LoginForm, ForgotPasswordForm, ResetPasswordForm
from app.utils import send_reset_email, user_has_capability
from itsdangerous import URLSafeTimedSerializer
from werkzeug.security import generate_password_hash, check_password_hash
import os
# IMport at last to avoid circular imports
from app.views import auth


@auth.route('/register', methods=['GET', 'POST'])
def register():  
    form = RegistrationForm()
    if form.validate_on_submit():
        user = User(username=form.username.data, email=form.email.data)
        hashed_password = bcrypt.generate_password_hash(form.password.data).decode('utf-8')
        user.password_hash = hashed_password
        # Assign default role 'contributor' to the new user 
        author_role = Role.query.filter_by(name='contributor').first() 
        if author_role: 
            user.roles.append(author_role)
        db.session.add(user)
        db.session.commit()
        flash('Registration successful. Please log in.', 'success')
        return redirect(url_for('auth.login'))
    return render_template('register.html', form=form)

现在我遇到的问题是：

• 如果我把auth_controller里register方法上的@auth.route('/register', methods=['GET', 'POST'])装饰器去掉，就会一直收到这个错误：

Not Found The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again

• 如果auth_controller里的register方法保留这个装饰器，我能访问到注册表单，但只能通过127.0.0.1:5000/auth/register访问，而不是127.0.0.1:5000/register（我并没有给这个路由定义url_prefix啊）

我到底哪里做错了？该怎么解决这个问题？

备注：内容来源于stack exchange，提问作者Ritesh Rijal