python - 求助,ValueError: View function did not return a response

Question

新手在学flask开发，看到《python web开发》第十章的用户资料，
在搞 管理员级别的资料编辑器 那里出问题了，
视图函数抛出异常，不能返回响应
百度，谷歌，sof无果。找好久了没解决，心塞
所以来寻求帮助，谢谢能提供帮助的人
这是整个文件夹
http://pan.baidu.com/s/1kV4sXcr

路由视图views.py：

@main.route('/edit-profile/<int:id>', methods=['GET', 'POST'])
@login_required
@admin_required
def edit_profile_admin(id):
    user = User.query.get_or_404(id)
    form = EditProfileAdminForm(user=user)
    if form.validate_on_submit():
        user.email = form.email.data
        user.username = form.username.data
        user.confirmed = form.confirmed.data
        user.role = Role.query.get(form.role.data)
        user.name = form.name.data
        user.location = form.location.data
        user.about_me = form.about_me.data
        db.session.add(user)
        flash('The profile has been updated.')
        return redirect(url_for('.user', username=user.username))
    form.email.data = user.email
    form.username.data = user.username
    form.confirmed.data = user.confirmed
    form.role.data = user.role_id
    form.name.data = user.name
    form.location.data = user.location
    form.about_me.data = user.about_me
    return render_template('edit_profile.html', form=form, user=user)

表单forms.py:

class EditProfileAdminForm(FlaskForm):
    email = StringField('Email', validators=[Required(), Length(1, 64),
        Email()])
    username = StringField('Username', validators=[
        Required(), Length(1, 64), Regexp('^[A-Za-z][A-Za-z0-9_.]*$', 0,
                                          'Username must have only letters,'
                                           'number, dots or underscores')])
    confirmed = BooleanField('Confirmed')
    role = SelectField('Role', coerce=int)
    name = StringField('Real name', validators=[Length(0, 64)])
    location = StringField('Location', validators=[Length(0, 64)])
    about_me = TextAreaField('About me')
    submit = SubmitField('Submit')
    
    def __init__(self, user, *args, **kwargs):
        super(EditProfileAdminForm, self).__init__(*args, **kwargs)
        self.role.choices = [(role.id, role.name)
                             for role in Role.query.order_by(Role.name).all()]
        self.user = user
        
    def validate_email(self, field):
        if field.data != self.user.email and \
                User.query.filter_by(email=field.date).first():
            raise ValidationError('Emai already registered.')
    
    def validate_username(self, field):
        if field.data !=self.user.username and \
                User.query.filter_by(username=field.data).first():
            raise ValidationError('Username already in use.')

模板edit_profile.html：

{% extends "base.html" %}
{% import "bootstrap/wtf.html" as wtf %}

{% block title %}Flasky - Edit Profile{% endblock %}

{% block page_content %}
<p class="page-header">
    <h1>Edit Your Profile</h1>
</p>
<p class="col-md-4">
    {{ wtf.quick_form(form) }}
</p>
{% endblock %}

Answer 1

Netizens helped find the problem. There is a problem with the custom decorator that checks user permissions decorators.py:

def permission_required(permission):
    def decorator(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            if not current_user.can(permission):
                abort(403)
                return f(*args, **kwargs) # 此行缩进错误，应在if语句外
        return decorated_function
    return decorator

Just modify it.

T.T, I am really careless.
Python code indentation problem, I checked it specifically. Netizens suggested using 4 spaces for indentation. It is too risky to use 1 tab key instead, because each editor has different definitions of the tab key, and it is easy to cause problems. . Although my problem is not with the tab key, I will still pay attention to this problem in the future.

But I still have a question, why does the error page throw a problem with the view function,
but not an error on the decorator side, for example (IndentationError):
@admin_required → def permission_required(permission)
Thank you